Incidence

Nasopharyngeal carcinoma arises in the lining of the nasal cavity and pharynx, and it accounts for about one-third of all cancers of the upper airways in children.[1,2]

Nasopharyngeal carcinoma is very uncommon in children younger than 10 years but increases in incidence to 0.8 cases per 1 million per year in children aged 10 to 14 years and 1.3 cases per million per year in children aged 15 to 19 years.[3-5]

The incidence of nasopharyngeal carcinoma is characterized by racial and geographic variations, with an endemic distribution among well-defined ethnic groups, such as inhabitants of some areas in North Africa and the Mediterranean basin, and, particularly, Southeast Asia. In the United States, the incidence of nasopharyngeal carcinoma is higher in black children and adolescents younger than 20 years.[4,5]

Risk Factors

Nasopharyngeal carcinoma is strongly associated with Epstein-Barr virus (EBV) infection. In addition to the serological evidence of infection in more than 98% of patients, EBV DNA is present as a monoclonal episome in the nasopharyngeal carcinoma cells, and tumor cells can have EBV antigens on their cell surface.[6] The circulating levels of EBV DNA and serologic documentation of EBV infection may aid in the diagnosis.[7] Specific HLA subtypes, such as the HLA A2Bsin2 haplotype, are associated with a higher risk of nasopharyngeal carcinoma.[1]

Histology

Three histologic subtypes of nasopharyngeal carcinoma are recognized by the World Health Organization (WHO):

• Type I—keratinizing squamous cell carcinoma.
• Type II—nonkeratinizing squamous cell carcinoma. Type II is distinguished by the presence of lymphoid infiltration as type IIa or IIb.
• Type III—undifferentiated carcinoma. Type III is distinguished by the presence of lymphoid infiltration as type IIIa or IIIb.

Children with nasopharyngeal carcinoma are more likely to have WHO type II or type III disease.[4,5]

Clinical Presentation

Signs and symptoms of nasopharyngeal carcinoma include the following:[2,8]

• Cervical lymphadenopathy.
• Nosebleeds.
• Nasal congestion and obstruction.
• Headache.
• Otalgia.
• Otitis media.

Given the rich lymphatic drainage of the nasopharynx, bilateral cervical lymphadenopathy is often the first sign of disease. The tumor spreads locally to adjacent areas of the oropharynx and may invade the skull base, resulting in cranial nerve palsy or difficulty with movements of the jaw (trismus).

Distant metastatic sites may include the bones, lungs, and liver.

Diagnostic and Staging Evaluation

Diagnostic tests will determine the extent of the primary tumor and the presence of metastases. Visualization of the nasopharynx by an otolaryngologist using nasal endoscopy and magnetic resonance imaging of the head and neck can be used to determine the extent of the primary tumor.

A diagnosis can be made from a biopsy of the primary tumor or enlarged lymph nodes of the neck. Nasopharyngeal carcinomas must be distinguished from all other cancers that can present with enlarged lymph nodes and from other types of cancer in the head and neck area. Thus, diseases such as thyroid cancer, rhabdomyosarcoma, non-Hodgkin lymphoma including Burkitt lymphoma, and Hodgkin lymphoma must be considered, as well as benign conditions such as nasal angiofibroma, which usually presents with epistaxis in adolescent males, infectious lymphadenitis, and Rosai-Dorfman disease.

Evaluation of the chest and abdomen by computed tomography (CT) and bone scan is performed to determine whether there is metastatic disease. Fluorine F 18-fludeoxyglucose positron emission tomography (PET)–CT may also be helpful in the evaluation of potential metastatic lesions.[9]

Stage Information for Childhood Nasopharyngeal Carcinoma

Tumor staging is performed using the tumor-node-metastasis (TNM) classification system of the American Joint Committee on Cancer.[10,11]

More than 90% of children and adolescents with nasopharyngeal carcinoma present with advanced disease (stage III/IV or T3/T4).[12,13] Population-based studies have reported that patients younger than 20 years had a higher incidence of advanced-stage disease than did adult patients.[4,5] However, less than 10% of children and adolescents with nasopharyngeal carcinoma presented with distant metastases at diagnosis.[12-14]

Prognosis

The overall survival of children and adolescents with nasopharyngeal carcinoma has improved over the last four decades; with state-of-the-art multimodal treatment, 5-year survival rates exceed 80%.[4,5,8,12-16] After controlling for stage, children with nasopharyngeal carcinoma have significantly better outcomes than do adults.[4,5] However, the intensive use of chemotherapy and radiation therapy results in significant acute and long-term morbidities, including subsequent neoplasms.[4,12,13,15]

Treatment of Newly Diagnosed Childhood Nasopharyngeal Carcinoma

Treatment of nasopharyngeal carcinoma is multimodal and includes the following:

1. Combined-modality therapy with chemotherapy and radiation. High-dose radiation therapy alone has a role in the management of nasopharyngeal carcinoma; however, studies in both children and adults show that combined-modality therapy with chemotherapy and radiation is the most effective way to treat nasopharyngeal carcinoma.

   1. Several studies have investigated the role of chemotherapy in the treatment of adult nasopharyngeal carcinoma. The use of concomitant chemoradiation therapy has been consistently associated with a significant survival benefit, including improved locoregional disease control and reduction in distant metastases.[17-19] The addition of neoadjuvant chemotherapy to concomitant chemoradiation has further improved outcomes, whereas the impact of adjuvant chemotherapy is less defined.[18,19]
   2. In children, most studies have used neoadjuvant chemotherapy with cisplatin and 5-fluorouracil (5-FU) followed by concomitant chemoradiation with single-agent cisplatin.[13,14,20][Level of evidence: 2A] Using this approach, 5-year overall survival (OS) estimates are consistently above 80%.[14,20]
      The following two modifications of this approach have been investigated:

      • The NPC-2003-GPOH study included a 6-month maintenance therapy phase with interferon-beta, and reported a 30-month OS estimate of 97.1%.[14]
      • A randomized prospective trial compared cisplatin and 5-FU with cisplatin, 5-FU, and docetaxel.[20][Level of evidence: 1iiA] The addition of docetaxel was not associated with improved outcome.
   3. While nasopharyngeal carcinoma is a very chemosensitive neoplasm, high radiation doses to the nasopharynx and neck (approximately 65–70 Gy) are required for optimal locoregional control.[17-19] However, in children, studies using neoadjuvant chemotherapy have shown that it is possible to reduce the radiation dose to 55 Gy to 60 Gy for good responders.[13,14]
2. Surgery. Surgery has a limited role in the management of nasopharyngeal carcinoma; the disease is usually considered unresectable because of extensive local spread.

The combination of cisplatin-based chemotherapy and high doses of radiation therapy to the nasopharynx and neck are associated with a high probability of hearing loss, hypothyroidism and panhypopituitarism, trismus, xerostomia, dental problems, and chronic sinusitis or otitis.[12,13,15]; [8][Level of evidence: 3iiiA] (Refer to the PDQ summary on Late Effects of Treatment for Childhood Cancer for more information.)

Treatment of Refractory Childhood Nasopharyngeal Carcinoma

Given the unique pathogenesis of nasopharyngeal carcinoma, immunotherapy has been explored for patients with refractory disease, as follows:

• The use of Epstein-Barr virus (EBV)–specific cytotoxic T-lymphocyte therapy has shown to be a very promising approach with minimal toxicity and evidence of significant antitumor activity in patients with relapsed or refractory nasopharyngeal carcinoma.[21] In a phase I/II study of EBV-specific cytotoxic T-lymphocyte therapy in patients with refractory disease, response rates were observed in 33.3% of patients, and long-term remissions were obtained in 62% of patients treated in their second or subsequent remission.[22]
• Anti–programmed death-ligand 1 (PD-L1) monoclonal antibodies have been studied in two phase II trials in adults with refractory nasopharyngeal carcinoma, with response rates of 20.5% to 25.9% (33% in patients with PD-L1–positive tumors) and evidence of long-term remissions.[23,24]

Treatment Options Under Clinical Evaluation for Childhood Nasopharyngeal Carcinoma

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

Esthesioneuroblastoma (also termed olfactory neuroblastoma) is a small round cell tumor arising from the nasal neuroepithelium that is distinct from primitive neuroectodermal tumors.[34-37] In children, esthesioneuroblastoma is a very rare malignancy, with an estimated incidence of 0.1 cases per 100,000 per year in children younger than 15 years.[38]

Despite its rarity, esthesioneuroblastoma is the most common cancer of the nasal cavity in pediatric patients, accounting for 28% of cases in a Surveillance, Epidemiology, and End Results (SEER) study.[39] In a series of 511 patients from the SEER database, there was a slight male predominance, the mean age at presentation was 53 years, and only 8% of cases were younger than 25 years.[40] Most patients were white (81%) and the most common tumor sites were the nasal cavity (72%) and ethmoid sinus (13%).[40] In a retrospective, multi-institutional review of 24 pediatric patients with esthesioneuroblastoma, the median age at presentation was 14 years and 75% of patients were female.[41]

Histology and Molecular Features

Esthesioneuroblastoma can be histologically confused with other small round cell tumors of the nasal cavity, including sinonasal undifferentiated carcinoma, small cell carcinoma, melanoma, and rhabdomyosarcoma. Esthesioneuroblastoma typically shows diffuse staining with neuron-specific enolase, synaptophysin, and chromogranins, with variable cytokeratin expression.[42]

Genomic analysis of 66 samples of olfactory neuroblastoma revealed that 64% of cases presented with classical histology, and these samples had no overlap with the methylation profile of other groups. These tumors had losses of chromosomes 1–4, 8–10, and 12 in almost all cases, and mutations in TP53 and DNMT3A were identified in 10% of the cases. The remaining samples clustered in three distinct groups representing known entities in the differential diagnosis and could be differentiated from the classical olfactory neuroblastoma group on the basis of their distinctive methylation pattern, as well as mutational profile, which included IDH2 mutations.[43]

Clinical Presentation

Most children present in the second decade of life with symptoms that include the following:

• Nasal obstruction.
• Epistaxis.
• Hyposmia.
• Exophthalmos.
• Nasopharyngeal mass, which may have local extension into the orbits, sinuses, or frontal lobe.

Prognostic Factors

Review of multiple case series of mainly adult patients indicate that the following may correlate with adverse prognosis:[44-46]

• Higher histopathologic grade.
• Positive surgical margin status.
• Metastases to the cervical lymph nodes.

Stage Information for Childhood Esthesioneuroblastoma

Tumors are staged according to the Kadish system (refer to Table 1). Correlated with Kadish stage, survival ranges from 90% (stage A) to less than 40% (stage D). Most patients present with locally advanced–stage disease (Kadish stages B and C) and almost one-third of patients have tumors at distant sites (Kadish stage D).[38,39,41]

Recent reports suggest that positron emission tomography–computed tomography (PET-CT) may aid in staging the disease.[47]

Treatment and Outcome of Childhood Esthesioneuroblastoma

The use of multimodal therapy optimizes the chances for survival, with more than 70% of children expected to survive 5 or more years after initial diagnosis.[38,48,49] A multi-institutional review of 24 patients younger than 21 years at diagnosis found a 5-year disease-free survival and overall survival of 73% to 74%.[41][Level of evidence: 3iiiA]

Treatment options according to Kadish stage include the following:[50]

1. Kadish stage A: Surgery alone with clear margins. Adjuvant radiation therapy is indicated in patients with close and positive margins or with residual disease.
2. Kadish stage B: Surgery followed by adjuvant radiation therapy. The role of adjuvant chemotherapy is controversial.
3. Kadish stage C: Neoadjuvant approach with chemotherapy, radiation therapy, or concurrent chemotherapy-radiation therapy followed by surgery.
4. Kadish stage D: Systemic chemotherapy and radiation therapy to local and metastatic sites.

The mainstay of treatment is surgery and radiation.[51] Newer techniques such as endoscopic sinus surgery may offer similar short-term outcomes to open craniofacial resection.[40]; [52][Level of evidence: 3iiiDii] Other techniques such as stereotactic radiosurgery and proton-beam therapy (charged-particle radiation therapy) may also play a role in the management of this tumor.[49,53]

Nodal metastases are seen in about 5% of patients. Routine neck dissection and nodal exploration are not indicated in the absence of clinical or radiological evidence of disease.[54] Management of cervical lymph node metastases has been addressed in a review article.[54]

Reports indicate promising results with the increased use of resection and neoadjuvant or adjuvant chemotherapy in patients with advanced-stage disease.[34,41,48,55,56]; [57][Level of evidence: 3iii] Chemotherapy regimens that have been used with efficacy include cisplatin and etoposide with or without ifosfamide;[50,58] vincristine, actinomycin D, and cyclophosphamide with or without doxorubicin; ifosfamide and etoposide; cisplatin plus etoposide or doxorubicin;[48] vincristine, doxorubicin, and cyclophosphamide;[59] and irinotecan plus docetaxel.[60][Level of evidence: 3iiA]

Treatment Options Under Clinical Evaluation for Childhood Esthesioneuroblastoma

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

The annual incidence of thyroid cancers is 4.8 to 5.9 cases per 1 million people aged 0 to 19 years, accounting for approximately 1.5% of all cancers in this age group.[61,62] Thyroid cancer incidence is higher in children aged 15 to 19 years (17.6 cases per 1 million people), and it accounts for approximately 8% of cancers arising in this older age group.[3,61] More thyroid carcinomas occur in females than in males.[63] The trend toward larger tumors suggests that diagnostic scrutiny is not the only explanation for the observed results.[64]

Two time-trend studies using the Surveillance, Epidemiology, and End Results (SEER) database have shown a 2% and 3.8% annual increase in the incidence of differentiated thyroid carcinoma in the United States among children, adolescents, and young adults in the 1973 to 2011 and 1984 to 2010 periods, respectively.[61,64] A similar trend towards an increase in the incidence of thyroid cancer among children, adolescents, and young adults over the last two decades has been documented in Canada.[65]

The incidence of thyroid cancer is higher in whites (5.3 cases per 1 million vs. 1.5 cases per 1 million in blacks) and female adolescents (8.1 cases per 1 million vs. 1.7 cases per 1 million in male adolescents).[61]

The papillary subtype is the most common, accounting for approximately 60% of the cases, followed by the papillary follicular variant subtype (20%–25%), the follicular subtype (10%), and the medullary subtype (<10%).The incidence of the papillary subtype and its follicular variant peaks between the ages of 15 and 19 years. The incidence of medullary thyroid cancer is the highest in the age group of 0 to 4 years and declines at older ages (refer to Figure 3).[62]

Figure 3. Incidence of pediatric thyroid carcinoma based on most frequent subtype per 100,000 as a percent of total cohort. Reprinted from International Journal of Pediatric Otorhinolaryngology, Volume 89, Sarah Dermody, Andrew Walls, Earl H. Harley Jr., Pediatric thyroid cancer: An update from the SEER database 2007–2012, Pages 121–126, Copyright (2016), with permission from Elsevier.

Risk Factors

Risk factors for pediatric thyroid cancer include the following:

• Radiation exposure. There is an excessive frequency of papillary thyroid adenoma and carcinoma after radiation exposure, either as result of environmental contamination or use of ionizing radiation for diagnosis or treatment.[66-69] (Refer to the Subsequent Neoplasms section of the PDQ summary on Late Effects of Treatment for Childhood Cancer for more information.) The risk increases after exposure to a mean dose of more than 0.05 Gy to 0.1 Gy (50–100 mGy), and follows a linear dose-response pattern up to 30 Gy and then declines, which is greater at younger age of exposure and persists more than 45 years after exposure.[69,70]
  Papillary thyroid carcinoma is the most frequent form of thyroid carcinoma diagnosed after radiation exposure.[70] Molecular alterations, including intrachromosomal rearrangements, are frequently found; among them, RET/PTC rearrangements are the most common.[70]
• Genetic inheritance. Genetic inheritance plays a role in a subset of thyroid carcinomas. In children, medullary thyroid carcinoma is caused by a dominantly inherited or de novo gain-of-function mutation in the RET proto-oncogene associated with multiple endocrine neoplasia (MEN) type 2, either MEN2A or MEN2B, depending on the specific mutation.[71] When occurring in patients with the MEN syndromes, thyroid cancer may be associated with the development of other types of malignant tumors. (Refer to the Multiple Endocrine Neoplasia [MEN] Syndromes and Carney Complex section of the PDQ summary on Unusual Cancers of Childhood Treatment for more information.)
• Family history. For thyroid carcinomas of follicular cells, only 5% to 10% are familial cancers. Of those, most familial cases are nonsyndromic, while only a minority occur in the setting of well-defined cancer syndromes with known germline alterations, including the following:[72,73]

  • APC-associated polyposis.
  • Carney complex.
  • PTEN hamartoma tumor syndrome.
  • Werner syndrome.
  • DICER1 syndrome.

Histology

Tumors of the thyroid are classified as adenomas or carcinomas.[74-76] Adenomas are benign, well circumscribed and encapsulated nodules that may cause enlargement of all or part of the gland, which extends to both sides of the neck and can be quite large; some tumors may secrete hormones. Transformation to a malignant carcinoma may occur in some cells, which may grow and spread to lymph nodes in the neck or to the lungs. Approximately 20% of thyroid nodules in children are malignant.[73,74]

The following histologies account for the general diagnostic category of carcinoma of the thyroid:

• Differentiated thyroid carcinoma: Papillary and follicular carcinoma are often referred to as differentiated thyroid carcinoma. The pathological classification of differentiated thyroid carcinomas in children is based on standard definitions set by the World Health Organization, and the criteria are the same for children and adults. Long-term outcomes for children and adolescents with differentiated thyroid carcinoma are excellent, with 10-year survival rates exceeding 95%.[61,62,73]

  • Papillary thyroid carcinoma: Papillary thyroid carcinoma accounts for 90% or more of all cases of differentiated thyroid carcinoma occurring during childhood and adolescence. Pediatric papillary thyroid carcinoma may present with a variety of histological variants: classic, solid, follicular, and diffuse sclerosing. Papillary thyroid carcinoma is frequently multifocal and bilateral, and metastasizes to regional lymph nodes in most children. Hematogenous metastases to the lungs occur in up to 25% of cases.[73]
  • Follicular thyroid cancer: Follicular thyroid cancer is uncommon. It is typically a unifocal tumor and more prone to initial hematogenous metastases to lungs and bones. Metastases to regional lymph nodes are uncommon. Histologic variants of follicular thyroid cancer include Hürthle cell (oncocytic), clear cell, and insular (poorly differentiated) carcinoma.[73]
• Medullary thyroid carcinoma: Medullary thyroid carcinoma is a rare form of thyroid carcinoma that originates from the calcitonin-secreting parafollicular C cells and accounts for less than 10% of all cases of thyroid carcinoma in children.[62] In children, medullary thyroid carcinoma is usually associated with RET germline mutations in the context of multiple endocrine neoplasia type 2 syndrome.[77]
• Anaplastic carcinoma: Less than 1% of pediatric thyroid carcinomas are anaplastic carcinoma.

Molecular Features

Clinical Presentation and Prognostic Factors

Diagnostic Evaluation

Initial evaluation of a child or adolescent with a thyroid nodule includes the following:

• Ultrasound of the thyroid.
• Serum thyroid-stimulating hormone (TSH) level.
• Serum thyroglobulin level.

Tests of thyroid function are usually normal, but thyroglobulin can be elevated.

Fine-needle aspiration as an initial diagnostic approach is sensitive and useful. However, in doubtful cases, open biopsy or resection should be considered.[73].

Treatment of Papillary and Follicular Thyroid Carcinoma

Treatment options for papillary and follicular (differentiated) thyroid carcinoma include the following:

1. Surgery.
2. Radioactive iodine ablation.

In 2015, the American Thyroid Association (ATA) Task Force on Pediatric Thyroid Cancer published guidelines for the management of thyroid nodules and differentiated thyroid cancer in children and adolescents. These guidelines (summarized below) are based on scientific evidence and expert panel opinion, with a careful assessment of the level of evidence.[73]

1. Preoperative evaluation.[73]

   1. A comprehensive ultrasound of all regions of the neck using a high-resolution probe and Doppler technique should be obtained by an experienced ultrasonographer. A complete ultrasound examination should be performed before surgery.
   2. The addition of cross-sectional imaging (contrast-enhanced computed tomography [CT] or magnetic resonance imaging) should be considered when there is concern about invasion of the aerodigestive tract. Importantly, if iodinated contrast agents are used, further evaluation and treatment with radioactive iodine may need to be delayed for 2 to 3 months until total body iodine burden decreases.
   3. Chest imaging (x-ray or CT) may be considered for patients with substantial cervical lymph node disease.
   4. Thyroid nuclear scintigraphy should be pursued only if the patient presents with a suppressed thyroid-stimulating hormone (TSH).
   5. The routine use of bone scan or fluorine F 18-fludeoxyglucose positron emission tomography (PET) is not recommended.
2. Surgery.[73]
   Pediatric thyroid surgery is ideally completed by a surgeon who has experience performing endocrine procedures in children and in a hospital with the full spectrum of pediatric specialty care.

   1. Thyroidectomy:
      For patients with papillary or follicular carcinoma, total thyroidectomy is the recommended treatment of choice. The ATA expert panel recommendation is based on data showing an increased incidence of bilateral (30%) and multifocal (65%) disease.
      In patients with a small unilateral tumor confined to the gland, a near-total thyroidectomy—whereby a small amount of thyroid tissue (<1%–2%) is left in place at the entry point of the recurrent laryngeal nerve or superior parathyroid glands—might be considered to decrease permanent damage to those structures.
      Total thyroidectomy also optimizes the use of radioactive iodine for imaging and treatment.
   2. Central neck dissection:

      • A therapeutic central neck lymph node dissection should be done in the presence of clinical evidence of central or lateral neck metastases.[81]
      • For patients without clinical evidence of gross extrathyroidal invasion or locoregional metastasis, a prophylactic central neck dissection may be considered on the basis of tumor focality and size of the primary tumor. However, because of the increased morbidity associated with central lymph node dissection, it is important to carefully individualize each case on the basis of the risks and benefits of the extent of dissection.[89]
   3. Lateral neck dissection:

      • Cytological confirmation of metastatic disease to lymph nodes in the lateral neck is recommended before surgery.
      • Routine prophylactic lateral neck dissection is not recommended.
3. Classification and risk assignment.[73]
   Despite the limited data in pediatrics, the ATA Task Force recommends the use of the tumor-node-metastasis (TNM) classification system to categorize patients into one of three risk groups. (Refer to the Stage Information for Thyroid Cancer section in the PDQ summary on Thyroid Cancer Treatment [Adult] for more information about the TNM system.) This categorization strategy is meant to define the risk of persistent cervical disease and help determine which patients should undergo postoperative staging for the presence of distant metastasis.

   1. ATA Pediatric Low Risk: Disease confined to the thyroid with N0 or NX disease or patients with incidental N1a (microscopic metastasis to a small number of central neck nodes). These patients are at lowest risk of distant disease but may still be at risk of residual cervical disease, especially if the initial surgery did not include central neck dissection.
   2. ATA Pediatric Intermediate Risk: Extensive N1a or minimal N1b disease. These patients are at low risk of distant metastasis but are at an increased risk of incomplete lymph node resection and persistent cervical disease.
   3. ATA Pediatric High Risk: Regionally extensive disease (N1b) or locally invasive disease (T4), with or without distant metastasis. Patients in this group are at the highest risk of incomplete resection, persistent disease, and distant metastasis.
4. Postoperative staging and long-term surveillance.[73]
   Initial staging should be performed within 12 weeks after surgery; the purpose is to assess for evidence of persistent locoregional disease and to identify patients who are likely to benefit from additional therapy with iodine I 131 (131I). The ATA Pediatric Risk Level (as defined above) helps determine the extent of postoperative testing.

   1. ATA Pediatric Low Risk:

      • Initial postoperative staging includes a TSH-suppressed thyroglobulin. A diagnostic iodine I 123 (123I) scan is not required.
      • TSH suppression should be targeted to serum levels of 0.5 to 1.0 mIU/L.
      • In patients with no evidence of disease, surveillance should include ultrasound at 6 months postoperatively and then annually for 5 years; and thyroglobulin levels (on hormone replacement therapy) every 3 to 6 months for 2 years and then annually.
   2. ATA Pediatric Intermediate Risk:

      • Initial postoperative staging includes a TSH-stimulated thyroglobulin and diagnostic 123I whole-body scan for further stratification and determination with 131I.
      • TSH suppression should be targeted to serum levels of 0.1 to 0.5 mIU/L.
      • In patients with no evidence of disease, surveillance should include ultrasound at 6 months postoperatively and then every 6 to 12 months for 5 years (and then less frequently); and thyroglobulin levels (on hormone replacement therapy) every 3 to 6 months for 3 years and then annually.
      • TSH-stimulated thyroglobulin and diagnostic 123I scan should be considered in 1 to 2 years for patients treated with 131I.
   3. ATA Pediatric High Risk:

      • Initial postoperative staging includes a TSH-stimulated thyroglobulin and diagnostic 123I whole-body scan for further stratification and determination with 131I.
      • TSH suppression should be targeted to serum levels of less than 0.1 mIU/L.
      • In patients with no evidence of disease, surveillance should include ultrasound at 6 months postoperatively and then every 6 to 12 months for 5 years (and then less frequently); and thyroglobulin levels (on hormone replacement therapy) every 3 to 6 months for 3 years and then annually.
      • TSH-stimulated thyroglobulin and, possibly, a diagnostic 123I scan in 1 to 2 years in patients treated with 131I.
   For patients with antithyroglobulin antibodies, consideration can be given to deferred postoperative staging to allow time for antibody clearance, except in patients with T4 or M1 disease.
5. Radioactive iodine ablation.[73]
   The goal of 131I therapy is to decrease the risks of recurrence and to decrease mortality by eliminating iodine-avid disease.

   1. The ATA Task Force recommends the use of 131I for the treatment of iodine-avid persistent locoregional or nodal disease that cannot be resected and known or presumed iodine-avid distant metastases. For patients with persistent disease after administration of 131I, the decision to pursue additional 131I therapy should be individualized on the basis of clinical data and previous response.
   2. To facilitate 131I uptake by residual iodine-avid disease, the TSH level should be above 30 mIU/L. This level can be achieved by withdrawing levothyroxine for at least 14 days. In patients who cannot mount an adequate TSH response or cannot tolerate profound hypothyroidism, recombinant human TSH may be used.
   3. Therapeutic 131I administration is commonly based on either empiric dosing or whole-body dosimetry. Based on the lack of data comparing empiric treatment and treatment informed by dosimetry, the ATA Task Force was unable to recommend one specific approach. However, because of the differences in body size and iodine clearance in children compared with adults, it is recommended that all activities of 131I should be calculated by experts with experience in dosing children.
   4. A posttreatment whole-body scan is recommended for all children 4 to 7 days after 131I therapy. The addition of single-photon emission CT with integrated conventional CT (SPECT/CT) may help to distinguish the anatomic location of focal uptake.
      While rare, late effects of 131I treatment include salivary gland dysfunction, bone marrow suppression, pulmonary fibrosis, and second malignancies.[90]

Treatment of Recurrent Papillary and Follicular Thyroid Carcinoma

Despite the more advanced disease at presentation compared with adults, children with differentiated thyroid cancer generally have an excellent survival with relatively few side effects.[61,62,64]

Treatment options for recurrent papillary and follicular thyroid carcinoma include the following:

1. Radioactive iodine ablation with iodine I 131 (131I).

Radioactive iodine ablation with 131I is usually effective after recurrence.[91] For patients with 131I-refractory disease, molecularly targeted therapies using kinase inhibitors may provide alternative therapies.

Tyrosine kinase inhibitors (TKIs) with documented efficacy for the treatment of adults include the following:

• Sorafenib. Sorafenib is a vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and RAS kinase inhibitor. In a randomized phase III trial, sorafenib improved progression-free survival (PFS) when compared with placebo (10.8 months vs. 5.8 months) in adult patients with radioactive iodine–refractory locally advanced or metastatic differentiated thyroid cancer.[92] Sorafenib was approved by the U.S. Food and Drug Administration (FDA) in November 2013 for the treatment of adults with late-stage metastatic differentiated thyroid carcinoma.
  Pediatric-specific data are very limited; however, in one case report, sorafenib produced a radiographic response in a patient aged 8 years with metastatic papillary thyroid carcinoma.[93]
• Lenvatinib. Lenvatinib is an oral VEGFR, fibroblast growth factor receptor, PDGFR, RET, and KIT inhibitor. In a phase III randomized study of adults with 131I-refractory differentiated thyroid cancer, lenvatinib was associated with a significant improvement in PFS and response rate when compared with a placebo.[94] Lenvatinib was approved by the FDA in February 2015 for the treatment of adults with progressive radioactive iodine–refractory differentiated thyroid carcinoma.
• BRAF inhibitors. In an open-label, nonrandomized phase II study of vemurafenib in adult patients with 131I-refractory metastatic or unresectable BRAF-V600E positive papillary thyroid carcinoma who had not been previously treated with a TKI, a response rate of 38.5% was documented.[95] For patients with metastatic or advanced BRAF V600E–mutated anaplastic thyroid carcinoma, the combination of dabrafenib with the MEK inhibitor trametinib has shown a response rate of 69%.[96]

(Refer to the PDQ summary on Thyroid Cancer Treatment [Adult] for more information.)

Treatment of Medullary Thyroid Carcinoma

Medullary thyroid carcinomas are commonly associated with the multiple endocrine neoplasia type 2 (MEN2) syndrome (refer to the Multiple Endocrine Neoplasia [MEN] Syndromes and Carney Complex section of the PDQ summary on Unusual Cancers of Childhood Treatment for more information).

Treatment options for medullary thyroid carcinoma include the following:

1. Surgery: Treatment for children with medullary thyroid carcinoma is mainly surgical. Investigators have concluded that prophylactic central node dissection should not be performed on patients with hereditary medullary thyroid cancer if their basal calcitonin serum levels are lower than 40 pg/mL.[89]
   Most cases of medullary thyroid carcinoma in children occur in the context of the MEN2A and MEN2B syndromes. In those familial cases, early genetic testing and counseling is indicated, and prophylactic surgery is recommended for children with the RET germline mutation. Strong genotype-phenotype correlations have facilitated the development of guidelines for intervention, including screening and age at which prophylactic thyroidectomy should occur. The American Thyroid Association has proposed the following guidelines for prophylactic thyroidectomy in children with hereditary medullary thyroid carcinoma (refer to Table 2).[88]

   Table 2. Risk Levels and Management Based on Common RET Mutations Detected on Genetic Screening^a

   View in own window

   	Medullary Thyroid Carcinoma Risk Level
   	Highest (MEN2B)	High (MEN2A)	Moderate (MEN2A)
   RET Mutation	M918T	A883F, C634F/G/R/S/W/Y	G533C, C609F/G/R/S/Y, C611F/G/S/Y/W, C618F/R/S, C620F/R/S, C630R/Y, D631Y, K666E, E768D, L790F, V804L, V804M, S891A, R912P
   Age for Prophylactic Thyroidectomy	Total thyroidectomy in the first year of life, ideally in the first months of life.	Total thyroidectomy at or before age 5 y based on serum calcitonin levels.	Total thyroidectomy to be performed when the serum calcitonin level is above the normal range or at convenience if the parents do not wish to embark on a lengthy period of surveillance.

   MEN2A = multiple endocrine neoplasia type 2A; MEN2B = multiple endocrine neoplasia type 2B.

   ^aAdapted from Wells et al.[88]

2. Tyrosine kinase inhibitor (TKI) therapy: A number of TKIs have been evaluated and approved for patients with advanced thyroid carcinoma.

   • Vandetanib. Vandetanib (an inhibitor of RET kinase, vascular endothelial growth factor receptor [VEGFR], and epidermal growth factor receptor signaling) is approved by the U.S. Food and Drug Administration (FDA) for the treatment of symptomatic or progressive medullary thyroid cancer in adult patients with unresectable, locally advanced, or metastatic disease. Approval was based on a randomized, placebo-controlled, phase III trial that showed a marked progression-free survival (PFS) improvement for patients randomly assigned to receive vandetanib (hazard ratio, 0.35); the trial also showed an objective response rate advantage for patients receiving vandetanib (44% vs. 1% for the placebo arm).[97,98]
     Children with locally advanced or metastatic medullary thyroid carcinoma were treated with vandetanib in a phase I/II trial. Of 16 patients, only 1 had no response, and 7 had a partial response, for an objective response rate of 44%. Disease in three of those patients subsequently recurred, but 11 of 16 patients treated with vandetanib remained on therapy at the time of the report. The median duration of therapy for the entire cohort was 27 months, with a range of 2 to 52 months.[99] A long-term outcome evaluation in a cohort of 17 children and adolescents with advanced medullary thyroid carcinoma who received vandetanib reported a median PFS of 6.7 years and a 5-year overall survival of 88.2%.[100]
   • Cabozantinib. Cabozantinib (an inhibitor of the RET and MET kinases and VEGFR) has also shown activity against unresectable medullary thyroid cancer (10 of 35 adult patients [29%] had a partial response).[101] Cabozantinib was approved by the FDA in November 2012 for the treatment of adults with metastatic medullary thyroid cancer.

(Refer to the Multiple Endocrine Neoplasia [MEN] Syndromes and Carney Complex section of the PDQ summary on Unusual Cancers of Childhood Treatment and the Treatment for those with MTC section in the PDQ summary on Genetics of Endocrine and Neuroendocrine Neoplasias for more information.)

Incidence

More than 90% of tumors and tumor-like lesions in the oral cavity are benign.[102-105] Oral cavity cancer is extremely rare in children and adolescents.[106,107] According to the Surveillance, Epidemiology, and End Results Stat Fact Sheets, only 0.6% of all cases are diagnosed in patients younger than 20 years, and in 2008, the age-adjusted incidence for this population was 0.24 cases per 100,000.

The incidence of cancer of the oral cavity and pharynx has increased in adolescent and young adult females, and this pattern is consistent with the national increase in orogenital sexual intercourse in younger females and human papillomavirus (HPV) infection.[108] It is currently estimated that the prevalence of oral HPV infection in the United States is 6.9% in people aged 14 to 69 years and that HPV causes about 30,000 oropharyngeal cancers. Furthermore, from 1999 to 2008, the incidence rates for HPV-related oropharyngeal cancer increased by 4.4% per year in white men and 1.9% in white women.[109-111] Current practices to increase HPV immunization rates in both boys and girls may reduce the burden of HPV-related cancers.[112,113]

Histology

Benign odontogenic neoplasms of the oral cavity include odontoma and ameloblastoma. The most common nonodontogenic neoplasms of the oral cavity are fibromas, hemangiomas, and papillomas. Tumor-like lesions of the oral cavity include lymphangiomas, granulomas, and Langerhans cell histiocytosis.[102-105] (Refer to the Oral cavity subsection in the PDQ summary on Langerhans Cell Histiocytosis Treatment for more information about Langerhans cell histiocytosis of the oral cavity.)

Malignant lesions of the oral cavity were found in 0.1% to 2% of a series of oral biopsies performed in children [102,103] and 3% to 13% of oral tumor biopsies.[104,105] Malignant tumor types include lymphomas (especially Burkitt) and sarcomas (including rhabdomyosarcoma and fibrosarcoma). Mucoepidermoid carcinomas of the oral cavity have rarely been reported in the pediatric and adolescent age group. Most are low or intermediate grade and have a high cure rate with surgery alone.[114]; [115][Level of evidence: 3iiiA]

Risk Factors

Diseases that can be associated with the development of oral cavity and/or head and neck squamous cell carcinoma include the following:[116-123]

• Fanconi anemia.
• Dyskeratosis congenita.
• Connexin mutations.
• Chronic graft-versus-host disease.
• Epidermolysis bullosa.
• Xeroderma pigmentosum.
• Human papillomavirus infection.

Outcome

Review of the Surveillance, Epidemiology, and End Results (SEER) database identified 54 patients younger than 20 years with oral cavity squamous cell carcinoma (SCC) between 1973 and 2006. Pediatric patients with oral cavity SCC were more often female and had better survival than adult patients. When differences in patient, tumor, and treatment-related characteristics are adjusted for, the two groups experienced equivalent survival.[114][Level of evidence: 3iA] A retrospective study of the National Cancer Database identified 159 patients younger than 20 years with SCC of the head and neck. Of these tumors, 55% originated in the oral cavity, and patients with laryngeal tumors had a better survival rate than did those who presented with oral cavity primary tumors.[124]

Treatment of Childhood Oral Cavity Cancer

Treatment of benign oral cavity tumors is surgical.

Treatment options for childhood oral cavity cancer include the following:

1. Surgery.
2. Chemotherapy.
3. Radiation therapy.

Management of malignant tumors of the oral cavity is dependent on histology and may include surgery, chemotherapy, and radiation.[125] Most reported cases of oral cavity squamous cell carcinoma managed with surgery alone have done well without recurrence.[114,126] (Refer to the PDQ summary on Lip and Oral Cavity Cancer Treatment [Adult] for more information.)

Langerhans cell histiocytosis of the oral cavity may require treatment in addition to surgery. (Refer to the PDQ summary on Langerhans Cell Histiocytosis Treatment for more information.)

Treatment Options Under Clinical Evaluation for Childhood Oral Cavity Cancer

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence and Outcome

Salivary gland tumors are rare and account for 0.5% of all malignancies in children and adolescents. After rhabdomyosarcoma, they are the most common tumor in the head and neck.[127,128] Salivary gland tumors may occur after radiation therapy and chemotherapy are given for treatment of primary leukemia or solid tumors.[129,130]

Overall 5-year survival in the pediatric age group is approximately 95%.[131] A review of the Surveillance, Epidemiology, and End Results database identified 284 patients younger than 20 years with tumors of the parotid gland.[132][Level of evidence: 3iA] Overall survival was 96% at 5 years, 95% at 10 years, and 83% at 20 years. Adolescents had higher mortality rates (7.1%) than did children younger than 15 years (1.6%; P = .23).

Clinical Presentation

Most salivary gland neoplasms arise in the parotid gland.[133-138] About 15% of these tumors arise in the submandibular glands or in the minor salivary glands under the tongue and jaw.[136] These tumors are most frequently benign but may be malignant, especially in young children.[139]

Histology and Molecular Features

The most common malignant salivary gland tumor in children is mucoepidermoid carcinoma, followed by acinic cell carcinoma and adenoid cystic carcinoma; less common malignancies include rhabdomyosarcoma, adenocarcinoma, and undifferentiated carcinoma.[127,136,138,140-142] Mucoepidermoid carcinoma is usually low or intermediate grade, although high-grade tumors do occur. Mammary analog secretory carcinoma (MASC) of the salivary gland is a newly described pathologic entity that has been seen in children. Too few cases of MASC have been described to characterize the clinical course of these tumors.[143]

Immunohistochemical and molecular profiling in a series of pediatric patients with salivary gland tumors showed similarities to those tumors observed in adults.[144] In one study, 12 of 12 tumors were positive for MECT1-MAML2 fusion transcripts. This reflects the common chromosome translocation t(11;19)(q21;p13) that is seen in adults with salivary gland tumors.[145]

Mucoepidermoid carcinoma is the most common type of treatment-related salivary gland tumor, and with standard therapy, the 5-year survival is about 95%.[142,146,147]

Treatment of Childhood Salivary Gland Tumors

Treatment options for childhood salivary gland tumors include the following:

1. Surgery.
2. Radiation therapy.

Radical surgical removal is the treatment of choice for salivary gland tumors whenever possible, with additional use of radiation therapy for high-grade tumors or tumors that have invasive characteristics such as lymph node metastasis, positive surgical margins, extracapsular extension, or perineural extension.[131,148,149]; [137][Level of evidence: 3iiiA] Parotid gland tumors are removed with the aid of neurological monitoring to prevent damage to the facial nerve.

One retrospective study compared proton therapy with conventional radiation therapy and found that proton therapy had a favorable acute toxicity and dosimetric profile.[150] Also, in a retrospective study, brachytherapy with iodine I 125 seeds was used to treat 24 children with mucoepidermoid carcinoma who had high-risk factors. Seeds were implanted within 4 weeks of surgical resection. With a median follow-up of 7.2 years, the disease-free and overall survival rates were 100%; no severe radiation-associated complications were reported.[151][Level of evidence: 3iiDi]

There are inadequate data regarding the efficacy of adjuvant chemotherapy in children.

(Refer to the PDQ summary on Salivary Gland Cancer Treatment [Adult] for more information.)

Treatment Options Under Clinical Evaluation for Childhood Salivary Gland Tumors

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Sialoblastoma

Sialoblastoma is a usually benign tumor presenting in the neonatal period, but has been reported to present as late as age 15 years. Sialoblastoma rarely metastasizes to the lungs, lymph nodes, or bones.[152]

Chemotherapy regimens with carboplatin, epirubicin, vincristine, etoposide, dactinomycin, doxorubicin, and ifosfamide have produced responses in two children with sialoblastoma.[153]; [154][Level of evidence: 3iiiDiv]

Childhood Laryngeal Cancer

Childhood Laryngeal Papillomatosis

Molecular Features

NUT midline carcinoma is a very rare and aggressive malignancy genetically defined by rearrangements of the NUT gene. In most cases (75%), the NUT gene on chromosome 15q14 is fused with the BRD4 gene on chromosome 19p13, creating chimeric genes that encode the BRD-NUT fusion proteins. In the remaining cases, NUT is fused to BRD3 on chromosome 9q34 or to NSD3 on chromosome 8p11;[171] these tumors are termed NUT-variant.[172]

Clinical Presentation and Outcome

Childhood midline tract carcinomas (NUT midline carcinomas) arise in midline epithelial structures, typically mediastinum and upper aerodigestive tract, and present as very aggressive undifferentiated carcinomas, with or without squamous differentiation.[173,174] Although the original description of this neoplasm was made in children and young adults, individuals of all ages can be affected.[172] A retrospective series with clinicopathologic correlation found that the median age at diagnosis of 54 patients was 16 years (range, 0.1–78 years).[175]

The outcome is very poor, with a median survival of less than 1 year. Preliminary data suggest that NUT-variant tumors may have a more protracted course.[172,173]

Treatment of Childhood Midline Tract Carcinoma

Treatment options for childhood midline tract carcinoma include the following:

1. Chemotherapy.
2. Surgery.
3. Radiation therapy.

Treatment of childhood midline tract carcinoma involving the NUT gene (NUT midline carcinoma) has included a multimodal approach with systemic chemotherapy, surgery, and radiation therapy. Cisplatin, taxanes, and alkylating agents have been used with some success; however, while early response is common, tumor progression occurs early in the course of the disease.[176]; [175][Level of evidence: 3iiiB] In a report from the NUT Midline Carcinoma Registry, 40 patients with primary tumors in the head and neck were evaluable. Two-year overall survival was 30%. The three long-term survivors (35, 72, and 78 months) underwent primary gross-total resection and received adjuvant therapy.[174][Level of evidence: 3iiA]

Preclinical studies have shown that the NUT-BRD4 fusion is associated with globally decreased histone acetylation and transcriptional repression; studies have also shown that this acetylation can be restored with histone deacetylase inhibitors, resulting in squamous differentiation and arrested growth in vitro and growth inhibition in xenograft models. Response to vorinostat has been reported in two separate cases of children with refractory disease, suggesting a potential role for this class of agents in the treatment of this malignancy.[177,178] The BET bromodomain inhibitors represent a promising class of agents that is being investigated for adults with this malignancy.[171]

Treatment Options Under Clinical Evaluation for Childhood Midline Tract Carcinoma

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following are examples of national and/or institutional clinical trials that are currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).
• NCT01587703 (A Study to Investigate the Safety, Pharmacokinetics, Pharmacodynamics, and Clinical Activity of GSK525762 in Subjects With NUT Midline Carcinoma and Other Cancers): This study is evaluating the safety, pharmacokinetic, and pharmacodynamic profiles observed after oral administration of GSK525762, a BET bromodomain inhibitor, as well as the tolerability and clinical activity, in patients with NUT midline carcinoma and other solid tumors. Patients aged 16 years and older are eligible for this study.
• NCT01987362 (A Two Part, Multicenter, Open-label Study of TEN-010 Given Subcutaneously): This is a phase I, nonrandomized, dose-escalating, open label, multicenter study of patients aged 18 years and older with histologically confirmed advanced solid tumors with progressive disease requiring therapy or NUT midline carcinoma. This study is evaluating the safety, tolerability, and pharmacokinetics of TEN-010, a small molecule bromodomain inhibitor.

Fibroadenoma

Fibroadenoma is the most frequent breast tumor seen in children.[2,3] Sudden rapid enlargement of a suspected fibroadenoma is an indication for needle biopsy or excision, as rare transformation leading to malignant phyllodes tumors has been reported.[4]

Breast Cancer

Tracheobronchial Tumors

Histology

Tracheobronchial tumors are a heterogeneous group of primary endobronchial lesions, and although adenoma implies a benign process, all varieties of tracheobronchial tumors on occasion display malignant behavior. The following histologic types have been identified (refer to Figure 4):[27-33]

• Carcinoid tumor (neuroendocrine tumor of the bronchus). Carcinoid tumors account for 80% to 85% of all tracheobronchial tumors in children.[27-31] It is the most common tracheobronchial tumor.
• Mucoepidermoid carcinoma. A slow-growing vascular polypoid mass of the airway that is the second most common (10%) pediatric tracheobronchial tumor.
• Inflammatory myofibroblastic tumors. These low-grade benign tumors account for 1% of pediatric tracheobronchial tumors, are commonly located in the upper trachea, and rarely metastasize.
• Rhabdomyosarcoma.
• Granular cell tumors. Malignant transformation has not been documented in pediatric patients.

Figure 4. The most representative primary tracheobronchial tumors are described with their more frequent location. Reprinted from Seminars in Pediatric Surgery, Volume 25, Issue 3, Patricio Varela, Luca Pio, Michele Torre, Primary tracheobronchial tumors in children, Pages 150–155, Copyright (2016), with permission from Elsevier.

Pleuropulmonary Blastoma

Incidence and Histology

Esophageal cancer is rare in the pediatric age group, although it is relatively common in older adults.[71,72] Most of these tumors are squamous cell carcinomas, although sarcomas can also arise in the esophagus. The most common benign tumor is leiomyoma.

Risk Factors, Clinical Presentation, and Diagnostic Evaluation

Risk factors include caustic ingestion, gastroesophageal reflux, and Barrett esophagus.[72] Symptoms are related to difficulty in swallowing and associated weight loss. Diagnosis is made by histologic examination of biopsy tissue.

Treatment

Treatment options for esophageal carcinoma include the following:[72]

1. External-beam intracavitary radiation therapy.
2. Chemotherapy (agents commonly used to treat carcinomas such as platinum derivatives, paclitaxel, and etoposide).
3. Surgery.

Prognosis is generally poor for this cancer, which rarely can be completely resected.

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

(Refer to the PDQ summary on adult Esophageal Cancer Treatment for more information.)

Thymoma

Thymic Carcinoma

The European Cooperative Study Group for Pediatric Rare Tumors identified 20 patients with thymic carcinoma between 2000 and 2012.[78] Complete resection was achieved in 1 of 20 patients with thymic carcinoma. Five patients with thymic carcinoma survived. Five-year OS for patients with thymic carcinoma was 21.0%.

Histology

Cardiac tumors are rare, with an autopsy frequency of 0.001% to 0.30%;[91] in one report, the percentage of cardiac surgeries performed as a result of cardiac tumors was 0.093%.[92]

The most common primary tumors of the heart are benign and include the following:[93-95]

• Rhabdomyoma.
• Myxoma.
• Teratoma.
• Fibroma.

Other benign tumors include histiocytoid cardiomyopathy tumors, hemangiomas, and neurofibromas (i.e., tumors of the nerves that innervate the muscles).[93,96-99]

Myxomas are the most common noncutaneous finding in Carney complex, a rare syndrome characterized by lentigines, cardiac myxomas or other myxoid fibromas, and endocrine abnormalities.[100-102] A mutation of the PRKAR1A gene is noted in more than 90% of the cases of Carney complex.[100,103]

Primary malignant pediatric heart tumors are rare and include the following:[93,104,105]

• Malignant teratoma.
• Lymphoma.
• Various sarcomas, including rhabdomyosarcoma, angiosarcoma, chondrosarcoma, synovial sarcoma, and infantile fibrosarcoma.

Secondary tumors of the heart include metastatic spread of rhabdomyosarcoma, other sarcomas, melanoma, leukemia, thymoma, and carcinomas of various sites.[91,93]

Risk Factors

The distribution of cardiac tumors in the fetal and neonatal period is different from that in older patients, with two-thirds of teratomas occurring during this period of life.[96] Multiple cardiac tumors noted in the fetal or neonatal period are highly associated with a diagnosis of tuberous sclerosis.[96,106] A retrospective review of 94 patients with cardiac tumors detected by prenatal or neonatal echocardiography showed that 68% of the patients exhibited features of tuberous sclerosis.[107] In another study, 79% of patients (15 of 19) with rhabdomyomas discovered prenatally had tuberous sclerosis, while 96% of those diagnosed postnatally had tuberous sclerosis. Most rhabdomyomas, whether diagnosed prenatally or postnatally, will spontaneously regress.[108]

Clinical Presentation and Diagnostic Evaluation

Patients may be asymptomatic and present with sudden death,[109][Level of evidence: 3iiiA] but about two-thirds of patients have symptoms that may include the following:

• Abnormalities of heart rhythm.
• Enlargement of the heart.
• Fluid in the pericardial sac.
• Congestive heart failure.
• Syncope.
• Stroke.
• Respiratory distress.[95]

The utilization of new cardiac MRI techniques can identify the likely tumor type in most children.[110] However, histologic diagnosis remains the standard for diagnosing cardiac tumors.

Treatment

Successful treatment may require surgery, debulking for progressive symptoms, cardiac transplantation, and chemotherapy that is appropriate for the type of cancer that is present.[111-113]; [114][Level of evidence: 3iiA]

Treatment options for cardiac tumors, according to tumor types, are as follows:

1. Rhabdomyoma. Although some lesions such as rhabdomyomas can regress spontaneously, some practitioners recommend prophylactic resection to prevent mass-related complications.[92,95,106]; [115][Level of evidence: 3iiDiii] Treatment with the mammalian target of rapamycin (mTOR) inhibitor everolimus has been reported to be associated with a decrease in the size of rhabdomyomas in patients with tuberous sclerosis.[106,116,117]
2. Sarcoma. Cardiac sarcomas have a poor outcome and can be treated with multimodal therapy; the use of preoperative chemotherapy may be of value in reducing tumor volume before surgery.
3. Other tumor types. Complete surgical excision of other lesions offers the best chance for cure, with postoperative complications seen in about one-third of patients and postoperative mortality rates in less than 10% of patients.[92,95]

In one series, 95% of patients were free from cardiac tumor recurrence at 10 years.[95]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence, Risk Factors, and Clinical Presentation

Mesothelioma is extremely rare in childhood, with only 2% to 5% of patients presenting during the first two decades of life.[118] Fewer than 300 cases in children have been reported.[119]

Mesothelioma may develop after successful treatment of an earlier cancer, especially after treatment with radiation.[120,121] The amount of exposure required to develop cancer is unknown. In adults, these tumors have been associated with exposure to asbestos, which was used as building insulation.[122] There is no information about the risk for children exposed to asbestos.

This tumor can involve the membranous coverings of the lung, the heart, or the abdominal organs.[123-125] These tumors can spread over the surface of organs, without invading far into the underlying tissue, and may spread to regional or distant lymph nodes.

Prognosis

Benign and malignant mesotheliomas cannot be differentiated using histologic criteria. A poor prognosis is associated with lesions that are diffuse and invasive and with those that recur. In general, the course of the disease is slow, and long-term survival is common.

Diagnostic Evaluation

Diagnostic thoracoscopy should be considered in suspicious cases to confirm diagnosis.[118]

Treatment

Treatment options for malignant mesothelioma include the following:

1. Surgery.
2. Radiation therapy.
3. Chemotherapy.

Radical surgical resection has been attempted with mixed results.[126] In adults, a multimodal therapy including extrapleural pneumonectomy and radiation therapy after combination chemotherapy with pemetrexed-cisplatin may achieve durable responses.[127][Level of evidence: 2A] However, this approach remains highly controversial.[128] In children, treatment with various chemotherapeutic agents used for carcinomas or sarcomas may result in partial responses.[125,129-131]

Hyperthermic chemotherapy has been used to treat adults with pleural mesothelioma.[132,133]

Pain is an infrequent symptom; however, if pain occurs, radiation therapy may be used for palliation.

Papillary serous carcinoma of the peritoneum may be mistaken for mesothelioma.[134] This tumor generally involves all surfaces lining the abdominal organs, including the surfaces of the ovary. Treatment includes surgical resection whenever possible and use of chemotherapy with agents such as cisplatin, carboplatin, and paclitaxel.

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

(Refer to the PDQ summary on adult Malignant Mesothelioma Treatment for more information.)

Incidence

The incidence of adrenocortical tumors in children is extremely low (only 0.2% of pediatric cancers).[1] Adrenocortical tumors appear to follow a bimodal distribution, with peaks during the first and fourth decades.[2,3] Childhood adrenocortical tumors typically present during the first 5 years of life (median age, 3–4 years), although there is a second, smaller peak during adolescence.[4-6]

In children, 25 new cases are expected to occur annually in the United States, for an estimated annual incidence of 0.2 to 0.3 cases per 1 million individuals.[7] Internationally, however, the incidence of adrenocortical tumors appears to vary substantially. It is particularly high in southern Brazil, where it is approximately 10 to 15 times that observed in the United States.[8-11]

Female sex is consistently predominant in most studies, with a female to male ratio of 1.6:1.0.[3,5,6]

Risk Factors

Germline TP53 mutations are almost always the predisposing factor. The likelihood of a TP53 germline mutation is highest in the first years of life and diminishes with age. Predisposing genetic factors have been implicated in more than 50% of the cases in North America and Europe and in 95% of the Brazilian cases. [12]

• In the non-Brazilian cases, relatives of children with adrenocortical tumors often, although not invariably, have a high incidence of other nonadrenal cancers (Li-Fraumeni syndrome). Germline mutations usually occur within the region coding for the TP53 DNA-binding domain (exons 5 to 8, primarily at highly conserved amino acid residues).[10,12]
• In the Brazilian cases, the patients’ families do not exhibit a high incidence of cancer, and a single, unique mutation at codon 337 in exon 10 of the TP53 gene is consistently observed.[11,13] In a Brazilian study, neonatal screening for the TP53 R337H mutation, which is prevalent in the region, identified 461 (0.27%) carriers among 171,649 of the newborns who were screened.[14] Carriers and relatives younger than 15 years were offered clinical screening. Adrenocortical tumors identified in the screening participants were smaller and more curable than the tumors found in carriers who did not elect to participate in screening.

Patients with Beckwith-Wiedemann and hemihyperplasia syndromes have a predisposition to cancer, and as many as 16% of their neoplasms are adrenocortical tumors.[15] Hypomethylation of the KCNQ1OT1 gene has also been associated with the development of adrenocortical tumors in patients without the phenotypic features of Beckwith-Wiedemann syndrome.[16] However, less than 1% of children with adrenocortical tumors have these syndromes.[17]

The distinctive genetic features of pediatric adrenocortical carcinoma have been reviewed.[18]

Histology

Unlike adult adrenocortical tumors, histologic differentiation of pediatric adenomas and carcinomas is difficult. However, approximately 10% to 20% of pediatric cases are adenomas.[2,4] The distinction between benign (adenomas) and malignant (carcinomas) tumors can be problematic. In fact, adenomas and carcinomas appear to share multiple genetic aberrations and may represent points on a continuum of cellular transformation.[19]

Macroscopically, adenomas tend to be well defined and spherical, and they never invade surrounding structures. They are typically small (usually <200 cm³), and some studies have included size as a criterion for adenoma. By contrast, carcinomas have macroscopic features suggestive of malignancy; they are larger, and they show marked lobulation with extensive areas of hemorrhage and necrosis. Microscopically, carcinomas comprise larger cells with eosinophilic cytoplasm, arranged in alveolar clusters. Several authors have proposed histologic criteria that may help to distinguish the two types of neoplasm.[20-22]

Morphologic criteria may not allow reliable distinction of benign and malignant adrenocortical tumors. Mitotic rate is consistently reported as the most important determinant of aggressive behavior.[23] IGF2 expression also appears to discriminate between carcinomas and adenomas in adults, but not in children.[24,25] Other histopathologic variables are also important, and risk groups may be identified on the basis of a score derived from tumor characteristics, such as tumor necrosis, mitotic rate, the presence of atypical mitoses, and venous, capsular, or adjacent organ invasion.[11,22,23]

Molecular Features

A study performed on 71 pediatric adrenocortical tumors (37 in a discovery cohort and 34 in an independent cohort) provided a description of the genomic landscape of pediatric adrenocortical carcinoma.[26]

• IGF2 overexpression. The most common genomic alteration, present in approximately 90% of cases, was copy number loss of heterozygosity for 11p15 with retention of the paternal allele resulting in IGF2 overexpression.
• TP53 mutations. TP53 mutations were commonly observed. Twelve of 71 cases had the Brazilian founder R337H TP53 germline mutation. Excluding the Brazilian founder mutation cases, TP53 germline mutations were observed in approximately one-third of cases, with somatic TP53 mutations observed in approximately 10% of the remaining cases, such that approximately 40% of non-Brazilian cases had TP53 mutations. Among cases with TP53 mutations, chromosome 17 loss of heterozygosity with selection against wild-type TP53 was present in virtually all cases.
• ATRX mutations. ATRX genomic alterations (primarily structural variants) were present in approximately 20% of cases. All ATRX alterations occurred in the presence of TP53 alterations. The co-occurrence of TP53 and ATRX mutations correlated with advanced stage, large tumor size, increased telomere length, and poor prognosis.
• CTNNB1 mutations. Activating CTNNB1 mutations were found in approximately 20% of cases and were mutually exclusive with TP53 germline alterations.

Clinical Presentation

Because pediatric adrenocortical tumors are almost universally functional, they cause endocrine disturbances, and a diagnosis is usually made 5 to 8 months after the first signs and symptoms emerge.[3,4]

• Virilization. Virilization (pubic hair, accelerated growth, enlarged penis, clitoromegaly, hirsutism, and acne) caused by an excess of androgen secretion is seen, alone or in combination with hypercortisolism, in more than 80% of patients.[11,27]
• Hyperestrogenism. Hyperestrogenism can also occur.[28]
• Cushing syndrome. Isolated Cushing syndrome is very rare (5% of patients), and it appears to occur more frequently in older children.[3-5,11,29]

Because of the hormone hypersecretion, it is possible to establish an endocrine profile for each particular tumor, which may facilitate the evaluation of response to treatment and monitor for tumor recurrence.[11]

Nonfunctional tumors are rare (<10%) and tend to occur in older children.[3]

Prognostic Factors

Overall, adverse prognostic factors for adrenocortical carcinoma include the following:

• Large tumor size. Tumor weight higher than 200 g or tumor volume greater than 200 cm³ have been associated with a worse outcome.[30,31] Patients with small tumors have an excellent outcome when treated with surgery alone, regardless of histologic features.[6,32,33]
• Metastatic disease.[6,30,31,33]
• Age. Age older than 4 or 5 years.[3,6,30,31,33]
• Microscopic tumor necrosis.[33]
• Para-aortic lymph node involvement.[33]
• Incomplete resection or spillage during surgery.[6,30,31]
• Low HLA class II antigen expression. A low expression of the HLA class II antigens HLA-DRA, HLA-DPA1, and HLA-DPB1 has been associated with older age, larger tumor size, presence of metastatic disease, and worse outcome.[34] In pediatric patients, increased expression of MHC class II genes, especially HLA-DPA1, is associated with a better prognosis.[35]

Stage I disease appears to be associated with a better prognosis.[33]

The overall probability of 5-year survival for children with adrenocortical tumors depends on stage and ranges from greater than 80% for patients with resectable disease to less than 20% for patients with metastases.[3-5,29-32,36]

A portion of patients with adrenocortical carcinoma do not have a germline TP53 mutation. A retrospective review of children with adrenocortical carcinoma identified 60 patients without germline TP53 mutations.[37] There was a strong female predominance (female to male ratio, 42:18) in this group of patients. Three-year progression-free survival (PFS) was 71.4%, and overall survival (OS) was 80.5%. Prognostic factors for this group were the same as the factors identified in previous analyses that did not segregate for TP53 germline status. Unfavorable prognostic features included older age, higher disease stage, heavier tumor weight, presence of somatic TP53 mutations, and higher Ki-67 labeling index. Ki-67 labeling index and age remained significantly associated with PFS after adjusting for stage and tumor weight.

Treatment

At the time of diagnosis, two-thirds of pediatric patients have limited disease (tumors can be completely resected), and the remaining patients have either unresectable or metastatic disease.[3]

Treatment of childhood adrenocortical tumors has evolved from the data derived from the adult studies, and the same guidelines are used. Surgery is the most important mode of therapy, and mitotane and cisplatin-based regimens, usually incorporating doxorubicin and etoposide, are recommended for patients with advanced disease.[10,11,38,39]; [5][Level of evidence: 3iiiA]

Treatment options for childhood adrenocortical tumors include the following:

1. Surgery: An aggressive surgical approach toward the primary tumor and all metastatic sites is recommended when feasible.[40,41] Because of tumor friability, rupture of the capsule with resultant tumor spillage is frequent (approximately 20% of initial resections and 43% of resections after recurrence).[3] When the diagnosis of adrenocortical tumor is suspected, laparotomy and a curative procedure are recommended rather than fine-needle aspiration, to avoid the risk of tumor rupture.[41,42] Laparoscopic resection is associated with a high risk of rupture and peritoneal carcinomatosis; thus, open adrenalectomy remains the standard of care.[43]
2. Mitotane and cisplatin-based regimens: In adults, mitotane is commonly used as a single agent in the adjuvant setting after complete resection.[38] Little information is available about the use of mitotane in children, although response rates appear to be similar to those seen in adults.[1,38]

   • A retrospective analysis in Italy and Germany identified 177 adult patients with completely resected adrenocortical carcinoma. Recurrence-free survival was significantly prolonged by the use of adjuvant mitotane. Benefit was present with 1 g to 3 g per day of mitotane and was associated with fewer toxic side effects than doses of 3 g to 5 g per day.[44] (Refer to the PDQ summary on adult Adrenocortical Carcinoma Treatment for more information.)
   • In a review of 11 children with advanced adrenocortical tumors treated with mitotane and a cisplatin-based chemotherapeutic regimen, measurable responses were seen in seven patients. The mitotane daily dose required for therapeutic levels was approximately 4 g/m², and therapeutic levels were achieved after 4 to 6 months of therapy.[38]
   • In the GPOH-MET 97 trial, mitotane levels greater than 14 mg/L correlated with better survival.[5,11]

The use of radiation therapy in pediatric patients with adrenocortical tumors has not been consistently investigated. Adrenocortical tumors are generally considered to be radioresistant. Furthermore, because many children with adrenocortical tumors carry germline TP53 mutations that predispose to cancer, radiation may increase the incidence of secondary tumors. One study reported that three of five long-term survivors of pediatric adrenocortical tumors died of secondary sarcoma that arose within the radiation field.[11,45]

(Refer to the PDQ summary on adult Adrenocortical Carcinoma Treatment for more information.)

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

Primary gastric tumors in children are rare, and carcinoma of the stomach is even more unusual.[46] In one series, gastric cancer in children younger than 18 years accounted for 0.11% of all gastric cancer cases seen over an 18-year period.[47] The frequency and death rate from stomach cancer has declined worldwide for the past 50 years with the introduction of food preservation practices such as refrigeration.[48] Rare cases of familial diffuse gastric cancer associated with CDH1 germline mutations have been reported in adolescents.[49]

Clinical Presentation and Diagnostic Evaluation

The tumor must be distinguished from other conditions such as non-Hodgkin lymphoma, malignant carcinoid, leiomyosarcoma, and various benign conditions or tumors of the stomach.[46] Symptoms of carcinoma of the stomach include the following:

• Vague upper abdominal pain, which can be associated with poor appetite and weight loss.
• Nausea and vomiting.
• Change in bowel habits.
• Poor appetite.
• Weakness.
• Helicobacter pylori infection.[47,50]
• Anemia. Many individuals become anemic but otherwise show no symptoms before the development of metastatic spread.

Fiberoptic endoscopy can be used to visualize the tumor or to take a biopsy sample to confirm the diagnosis. Confirmation can also involve an x-ray examination of the upper gastrointestinal tract.

Treatment and Outcome

Treatment options for gastric carcinoma include the following:

1. Surgery.
2. Radiation therapy and chemotherapy.

Treatment includes surgical excision with wide margins. For individuals who cannot have a complete surgical resection, radiation therapy may be used along with chemotherapeutic agents such as fluorouracil (5-FU) and irinotecan.[51] Other agents that may be of value are the nitrosoureas with or without cisplatin, etoposide, doxorubicin, or mitomycin C.

Prognosis depends on the extent of the disease at the time of diagnosis and the success of treatment that is appropriate for the clinical situation.[47] Because of the rarity of stomach cancer in the pediatric age group, little information exists regarding the treatment outcomes of children.

(Refer to the Gastrointestinal Stromal Tumors [GIST] section of this summary for information about the treatment of GIST.)

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Solid Pseudopapillary Tumor of the Pancreas

Pancreatoblastoma

Islet Cell Tumors

Pancreatic Carcinoma

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

Carcinoma of the large bowel is rare in the pediatric age group.[76] It is seen in one case per 1 million persons younger than 20 years in the United States annually; fewer than 100 cases are diagnosed in children each year in the United States.[77] From 1973 to 2006, the Surveillance, Epidemiology, and End Results (SEER) database recorded 174 cases of colorectal cancer in patients younger than 19 years.[78] Colorectal carcinoma accounts for about 2% of all malignancies in patients aged 15 to 29 years.[79]

Clinical Presentation

Colorectal tumors can occur in any location in the large bowel. Larger series and reviews suggest that ascending and descending colon tumors are each seen in approximately 30% of cases, with rectal tumors occurring in approximately 25% of cases.[80-82]

Signs and symptoms in children with descending colon tumors include the following:

• Abdominal pain (most common).
• Rectal bleeding.
• Change in bowel habits.
• Weight loss.
• Nausea and vomiting.

The median duration of symptoms before diagnosis was about 3 months in one series.[77,83]

Changes in bowel habits may be associated with tumors of the rectum or lower colon.

Tumors of the right colon may cause more subtle symptoms but are often associated with the following:

• Abdominal mass.
• Weight loss.
• Decreased appetite.
• Blood in the stool
• Iron-deficiency anemia.

Any tumor that causes complete obstruction of the large bowel can cause bowel perforation and spread of the tumor cells within the abdominal cavity.

Diagnostic Evaluation

Diagnostic studies include the following:[84,85]

• Examination of the stool for blood.
• Studies of liver and kidney function.
• Measurement of carcinoembryonic antigen (CEA).
• Various medical imaging studies, including direct examination using colonoscopy to detect polyps in the large bowel. Other conventional radiographic studies include barium enema or video-capsule endoscopy followed by computed tomography of the chest and bone scans.[86]

Histology and Molecular Features

There is a higher incidence of mucinous adenocarcinoma in the pediatric and adolescent age group (40%–50%), with many lesions being the signet ring cell type,[76,77,83,87,88] whereas only about 15% of adult lesions are of this histology. The tumors of younger patients with this histologic variant may be less responsive to chemotherapy. In the adolescent and young adult population with the mucinous histology, there is a higher incidence of signet ring cells, microsatellite instability, and mutations in the mismatch repair genes.[88-90] Tumors with mucinous histology arise from the surface of the bowel, usually at the site of an adenomatous polyp. The tumor may extend into the muscle layer surrounding the bowel, or the tumor may perforate the bowel entirely and seed through the spaces around the bowel, including intra-abdominal fat, lymph nodes, liver, ovaries, and the surface of other loops of bowel. A high incidence of metastasis involving the pelvis, ovaries, or both may be present in girls.[85]

Colorectal cancers in younger patients with noninherited sporadic tumors often lack KRAS mutations and other cytogenetic anomalies seen in older patients.[91] In a genomic study that used exome and RNA sequencing to identify mutational differences in colorectal carcinomas of adults (n = 30), adolescents and young adults (n = 30), and children (n = 2), five genes (MYCBP2, BRCA2, PHLPP1, TOPORS, and ATR) were identified that were more frequently mutated in adolescents and young adult patients. These genes contained a damaging mutation and were identified through whole-exome sequencing and RNA sequencing. In addition, higher mutational rates in DNA mismatch and DNA repair pathways, such as MSH2, BRCA2, and RAD9B, were more prevalent in adolescent and young adult samples but the results were not validated by RNA sequencing.[92]

Staging

Most reports also suggest that children present with more advanced disease than do adults, with 80% to 90% of patients presenting with Dukes stage C/D or TNM stage III/IV disease (refer to the Stage Information for Colon Cancer section of the PDQ summary on adult Colon Cancer Treatment for more information about staging).[77,80-84,87,88,93-99]

Treatment and Outcome

Most patients present with evidence of metastatic disease,[83] either as gross tumor or as microscopic deposits in lymph nodes, on the surface of the bowel, or on intra-abdominal organs.[87,93] Of almost 160,000 patients with colorectal cancer included in the National Cancer Database, 918 pediatric patients were identified. Age younger than 21 years was a significant predictor of increased mortality.[88]

Treatment options for childhood colorectal cancer include the following:

1. Surgery: Complete surgical excision is the most important prognostic factor and is the primary goal of surgery, but in most instances, this is impossible. Removal of large portions of tumor provides little benefit for those with extensive metastatic disease.[77] Most patients with microscopic metastatic disease generally develop gross metastatic disease, and few individuals with metastatic disease at diagnosis become long-term survivors.
2. Radiation therapy and chemotherapy: Current therapy includes the use of radiation for rectal and lower colon tumors, in conjunction with chemotherapy using 5-FU with leucovorin.[100] Other agents, including irinotecan, may be of value.[83][Level of evidence: 3iiiA] No significant benefit has been determined for interferon-alfa given in conjunction with 5-FU/leucovorin.[101]
   A recent review of nine clinical trials comprising 138 patients younger than 40 years demonstrated that the use of combination chemotherapy improved PFS and OS in these patients. Furthermore, OS and response rates to chemotherapy were similar to those observed in older patients.[102][Level of evidence: 2A]
   Other active agents used in adults include oxaliplatin, bevacizumab, panitumumab, cetuximab, aflibercept, and regorafenib.[103- 106]

Survival is consistent with the advanced stage of disease observed in most children with colorectal cancer, with an overall mortality rate of approximately 70%. For patients with a complete surgical resection or for those with low-stage/localized disease, survival is significantly prolonged, with the potential for cure.[80]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Genetic Syndromes Associated With Colorectal Cancer

About 20% to 30% of adult patients with colorectal cancer have a significant history of familial cancer; of these, about 5% have a well-defined genetic syndrome.[107]

The incidence of these genetic syndromes in children has not been well defined, as follows:

• In one review, 16% of patients younger than 40 years had a predisposing factor for the development of colorectal cancer.[108]
• A later study documented immunohistochemical evidence of mismatch repair deficiency in 31% of colorectal carcinoma samples in patients aged 30 years or younger.[109]
• A retrospective review of patients younger than 18 years in Germany identified 31 patients with colorectal carcinoma.[110] Eleven of the 26 patients who were tested for a genetic predisposition syndrome tested positive (eight cases of Lynch syndrome, one patient with familial adenomatous polyposis, and two patients with constitutional mismatch repair deficiency). When compared with the patients without a genetic predisposition syndrome, the 11 patients with a genetic predisposition syndrome presented with more localized disease, allowing complete surgical resection and improved outcome (100% survival).

The most common genetic syndromes associated with the development of colorectal cancer are shown in Tables 4 and 5. (Refer to the PDQ summary on Genetics of Colorectal Cancer for more information about the genetic syndromes associated with childhood colorectal cancer.)

Familial polyposis is inherited as a dominant trait, which confers a high degree of risk. Early diagnosis and surgical removal of the colon eliminates the risk of developing carcinomas of the large bowel.[111] Some colorectal carcinomas in young people, however, may be associated with a mutation of the adenomatous polyposis coli (APC) gene, which also is associated with an increased risk of brain tumors and hepatoblastoma.[112] Familial adenomatous polyposis (FAP) syndrome is caused by mutation of a gene on chromosome 5q, which normally suppresses proliferation of cells lining the intestine and later development of polyps.[113] A double-blind, placebo-controlled, randomized phase I trial in children aged 10 to 14 years with FAP reported that celecoxib at a dose of 16 mg/kg per day is safe for administration for up to 3 months. At this dose, there was a significant decrease in the number of polyps detected on colonoscopy.[114][Level of evidence: 1iiDiv] The role of celecoxib in the management of FAP in children is not clear.

Another tumor suppressor gene on chromosome 18 is associated with progression of polyps to malignant form. Multiple colon carcinomas have been associated with neurofibromatosis type I and several other rare syndromes.[115]

Despite the increased risk of multiple malignancies in families with Lynch syndrome, the risk of malignant neoplasms during childhood in those families does not seem to be increased when compared with the risk in children from non-Lynch syndrome colorectal carcinoma families.[116]

Neuroendocrine Tumors of the Appendix

Nonappendiceal Neuroendocrine Tumors

Metastatic Neuroendocrine Tumors

Treatment of metastatic carcinoid tumors of the large bowel, pancreas, or stomach becomes more complicated and requires treatment similar to that given for adult high-grade neuroendocrine tumors. (Refer to the PDQ summary on adult Gastrointestinal Carcinoid Tumors Treatment for treatment options in patients with malignant carcinoid tumors.)

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms of the gastrointestinal tract in adults.[144] These tumors are rare in children.[145] Approximately 2% of all GIST occur in children and young adults.[146-148] In one series, pediatric GIST accounted for 2.5% of all pediatric nonrhabdomyosarcomatous soft tissue sarcomas.[149] Previously, these tumors were diagnosed as leiomyomas, leiomyosarcomas, and leiomyoblastomas.

In pediatric patients, GIST are most commonly located in the stomach and almost exclusively affect adolescent females.[148,150,151]

Histology and Molecular Features

Histologically, pediatric GIST have a predominance of epithelioid or epithelioid/spindle cell morphology and, unlike adult GIST, the mitotic rate does not appear to accurately predict clinical behavior.[150,152] The majority of GIST in the pediatric age range have loss of the succinate dehydrogenase (SDH) complex and consequently, lack SDHB expression by immunohistochemistry.[153,154] In addition, these tumors have minimal large-scale chromosomal changes and overexpress the insulin-like growth factor 1 receptor.[155,156]

Activating mutations of KIT and PDGFA, which are seen in 90% of adult GIST, are present in only a small fraction of pediatric GIST.[150,155,157] The lack of SDHB expression in most pediatric GIST implicates cellular respiration defects in the pathogenesis of this disease and supports the notion that this disease is better categorized as SDH-deficient GIST. Furthermore, about 50% of patients with SDH-deficient GIST have germline mutations of the SDH complex, most commonly involving SDHA,[153] supporting the notion that SDH-deficient GIST is a cancer predisposition syndrome and testing of affected patients for constitutional mutations for the SDH complex should be considered.[158] A small percentage of SDH-deficient GIST lack somatic or germline mutations of the SDH complex and are characterized by SDHC promoter hypermethylation and gene silencing and are categorized as SDH-epimutant GIST.[159]

In an observational study carried out at the NCI, 116 patients with presumed wild-type GIST were evaluated, and 95 of these patients had an adequate tumor specimen available for molecular profiling. Among these 95 patients, the investigators identified the following three distinctive subgroups of patients:[160]

• Group 1 (SDH-competent GIST): Group 1 was comprised of 11 patients who were designated as SDH competent because of positive staining of SDHB and lack of mutations on sequencing. All of these patients were adults, the median age was 46 years, and 64% were female. The tumors arose primarily in the small bowel (9 of 11), one patient had metastases to the peritoneum, and one patient had multifocal disease. Mutational analysis of these tumors identified mutations in the BRAF, NF1, CBL, KIT, and ARID1A genes. With a median follow-up of 8 years, three of these patients (27%) died of progressive disease.
• Group 2 (SDHX-mutant GIST): Group 2 was comprised of 63 patients who were SDH deficient and contained mutations in the SDHA (n = 34), SDHB (n = 16), SDHC (n = 12), and SDHD (n = 1) complexes. Of the 38 patients with SDH-mutant GIST who had matching germline and tumor DNA, 31 (82%) had the same mutation detected in the germline and the tumor. This group of patients was younger (median age, 23 years), mostly female (62%), and presented with gastric tumors (100%) and multifocal disease (42%). Metastases at presentation were seen in the lymph nodes (65%), liver (21%), and peritoneum (10%). At a median follow-up from diagnosis of 6 years, only three patients (5%) had died.
• Group 3 (SDHC-epimutant GIST): Group 3 was comprised of 21 patients with SDH-deficient tumors, with SDHC promoter methylation and no structural mutations. The median age at diagnosis was younger (age 15 years) and most patients were female (95%). All tumors arose in the stomach; 72% were multifocal; and metastases were present at diagnosis in the liver (37%), peritoneum (5%), and lymph nodes (38%). At a median follow-up of 7 years, only one patient (5%) with an SDH-epimutant tumor died from disease.

Of the 95 patients that were evaluated at this clinic, 18 patients had syndromic GIST (i.e., Carney triad or Carney-Stratakis syndrome). Among the Carney triad patients, two patients had the complete triad, five patients had SDH mutations, and six patients had epimutant tumors. Seven patients with Carney-Stratakis syndrome had SDH-mutant GIST (n = 6) or SDH-epimutant GIST (n = 1).[160]

Clinical Features

Most pediatric patients with GIST are diagnosed during the second decade of life with anemia-related gastrointestinal bleeding. In addition, pediatric GIST have a high propensity for multifocality (23%) and nodal metastases.[148,150,157] These features may account for the high incidence of local recurrence seen in this patient population. Despite these features, patients have an indolent course characterized by multiple recurrences and long survival.[157]

SDH-deficient GIST can arise within the context of the following two syndromes:[150,161]

• Carney triad. Carney triad is a syndrome characterized by the occurrence of GIST, lung chondromas, and paragangliomas. In addition, about 20% of patients have adrenal adenomas and 10% have esophageal leiomyomas. GIST are the most common (75%) presenting lesions in these patients. To date, no coding sequence mutations of KIT, PDGFR, or the SDH genes have been found in these patients.[148,161,162]
• Carney-Stratakis syndrome. Carney-Stratakis syndrome is characterized by paraganglioma and GIST caused by germline mutations of the SDH genes B, C, and D.[154,163]

Treatment

Once the diagnosis of pediatric GIST is established, referral to medical centers with expertise in the treatment of GIST should be considered, with all samples evaluated for mutations in KIT (exons 9, 11, 13, 17), PDGFR (exons 12, 14, 18), and BRAF (V600E).[164,165]

Treatment options for GIST depend on whether a mutation is detected, as follows:

1. GIST with a KIT or PDGFR mutation: Pediatric patients who harbor KIT or PDGFR mutations are managed according to adult guidelines.
2. SDH-deficient GIST: Approximately one-half of all wild-type GIST patients are SDH-deficient.[166] For most pediatric patients with SDH-deficient GIST, because of its indolent course, surgical resection of localized disease is recommended while avoiding extensive surgery and repeated surgical resections. These recommendations are supported by a study of 76 patients with wild-type GIST who underwent surgery for newly diagnosed and recurrent disease.[166] In this study, only 9% of patients experienced a fatal event, whereas 71% (54 patients) developed recurrence or progression at a median of 2.5 years. For this population, the 1-year event-free survival (EFS) was 73%, the 5-year EFS was 24%, and the 10-year EFS was 16%. Factors associated with an increased risk of recurrence included metastatic disease and elevated mitotic rate; SDH status and extent of surgical resection did not influence the risk of recurrence. Among 33 patients who underwent reoperation for recurrent disease, each subsequent resection was associated with a lower EFS.
   Responses to imatinib and sunitinib in pediatric patients with SDH-deficient GIST are uncommon and consist mainly of disease stabilization.[150,167,168] In a review of ten patients who were treated with imatinib mesylate, one patient experienced a partial response and three patients had stable disease.[150] In the phase III SWOG intergroup trial S0033 (NCT00009906), 20 tumors from patients who were presumed to be wild-type were resequenced.[168] Twelve of these tumors were identified as being SDH mutant, and only one patient (8.3%) experienced a partial response to imatinib.[169] In another study, sunitinib appeared to show more activity, with one partial response and five cases of stable disease in six children with imatinib-resistant GIST.[170] Unlike the adult recommendations, the use of adjuvant imatinib cannot be recommended in children with SDH-deficient GIST.[171]
   Given the indolent course of the disease in pediatric patients, it is reasonable to avoid extensive initial surgeries and to withhold subsequent resections unless they are needed to address only symptoms such as obstruction or bleeding.[145,150]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following are examples of national and/or institutional clinical trials that are currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).
• NCT03165721 (A Phase II Trial of the DNA Methyl Transferase Inhibitor, Guadecitabine [SGI-110], in Children and Adults With Wild-Type GIST, Pheochromocytoma and Paraganglioma Associated With Succinate Dehydrogenase Deficiency and HLRCC-associated Kidney Cancer): Participants will be injected with SGI-110 under the skin each day for 5 days. This cycle will repeat every 28 days. The cycles repeat until toxicity occurs or the disease progresses.

Clinical Presentation

Urothelial bladder neoplasms are extremely rare in children; the most common presenting symptom is hematuria.[1]

Risk Factors

Bladder cancer in adolescents may develop as a consequence of alkylating-agent chemotherapy given for other childhood tumors or leukemia.[2-4] The association between cyclophosphamide and bladder cancer is the only established relationship between a specific anticancer drug and a solid tumor.[2]

Histology

Histologic classification of these neoplasms includes the following:

• Urothelial papillomas.
• Papillary neoplasms of low malignant potential.
• Low-grade urothelial carcinoma.
• High-grade urothelial carcinoma.

An alternative designation is transitional cell carcinoma of the bladder. The most common histology is papillary urothelial neoplasm of low malignant potential, while high-grade, invasive urothelial carcinomas are extremely rare in young patients.[4-8]

Treatment and Outcome

Treatment options for childhood bladder cancer include the following:

1. Surgery.

In contrast to adults, most pediatric bladder carcinomas are low grade, superficial, and have an excellent prognosis after transurethral resection.[6-9] Squamous cell carcinoma and more aggressive carcinomas, however, have been reported and may require a more aggressive surgical approach.[7,10-12]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

(Refer to the PDQ summary on adult Bladder Cancer Treatment for more information.)

Incidence and Clinical Presentation

Testicular tumors are very rare in young boys and account for an incidence of 1% to 2% of all childhood tumors.[13,14] The most common testicular tumors are benign teratomas followed by malignant nonseminomatous germ cell tumors. (Refer to the PDQ summary on Childhood Extracranial Germ Cell Tumors Treatment for more information.)

Non–germ cell tumors such as sex cord–stromal tumors are exceedingly rare in prepubertal boys. In a small series, gonadal stromal tumors accounted for 8% to 13% of pediatric testicular tumors.[15,16] Most gonadal stromal tumors present as a painless testicular mass, while 10% to 20% of patients may have endocrine manifestations such as precocious puberty.[17] In newborns and infants, juvenile granulosa cell and Sertoli cell tumors are the most common stromal cell tumor. Juvenile granulosa cell tumors usually present in infancy (median age, 6 days) and Sertoli cell tumors present later in infancy (median age, 7 months). In older males, Leydig cell tumors are more common.[18] Large cell calcifying Sertoli cell tumors may indicate an underlying genetic predisposition, such as Peutz-Jeghers syndrome or Carney complex. These tumors may occur in both testes, and some patients may have a slow and indolent course.[19]

Prognosis

The prognosis for sex cord–stromal tumors is usually excellent after orchiectomy.[17,20,21]; [22][Level of evidence: 3iiiA] In a review of the literature, 79 patients younger than 12 years were identified. No patient had high-risk pathological findings after orchiectomy, and none had evidence of occult metastatic disease, suggesting a role for a limited surveillance strategy.[23][Level of evidence: 3iiiA]

Treatment

Treatment options for testicular cancer (non-germ cell) include the following:

1. Surgery.

There are conflicting data about malignant potential in older males. Most case reports suggest that in the pediatric patients, these tumors can be treated with surgery alone.[20][Level of evidence: 3iii]; [24][Level of evidence: 3iiiA]; [17][Level of evidence: 3iiiDii] It is prudent to check alpha-fetoprotein (AFP) levels before surgery. Elevated AFP levels are usually indicative of a malignant germ cell tumor. However, AFP levels and decay in levels are often difficult to interpret in infants younger than 1 year.[25]

Evidence (surgery):

1. In a study of patients prospectively reported to the German Maligne Keimzelltumoren (MAKEI) registry, 42 patients with sex cord–stromal tumors were identified. All tumors were confined to the testes. Patients were treated with surgery alone, according to specific germ cell tumor guidelines.[22][Level of evidence: 3iiiA]

   • There were no recurrences.
2. A French registry identified 11 boys with localized sex cord–stromal testicular tumors. All 11 boys were treated with surgery alone.[26][Level of evidence: 3iA]

   • There were no recurrences.
3. The benign behavior of pediatric non–germ cell testicular tumors has led to reports of testis-sparing surgery.[27-29]

However, given the rarity of this tumor, the surgical approach in pediatrics has not been well defined.

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Epithelial Ovarian Neoplasia

Sex Cord–Stromal Tumors

Small Cell Carcinoma of the Ovary, Hypercalcemia-Type

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following are examples of national and/or institutional clinical trials that are currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).
• EZH-202 (NCT02601950) (A Phase II, Multicenter Study of the EZH2 Inhibitor Tazemetostat in Adult Subjects With INI1-Negative Tumors or Relapsed/Refractory Synovial Sarcoma): This is a phase II, multicenter, open-label, single-arm, two-stage study of tazemetostat. Patients receive 800 mg (orally) of tazemetostat twice a day in continuous 28-day cycles. Eligible subjects will be enrolled into one of five cohorts on the basis of their tumor type. Patients aged 16 years and older are eligible for this study.

Incidence, Risk Factors, and Clinical Presentation

Adenocarcinoma of the cervix and vagina is rare in childhood and adolescence, with fewer than 50 reported cases.[33,72] Two-thirds of the cases are related to exposure to diethylstilbestrol in utero.

The median age at presentation is 15 years, with a range of 7 months to 18 years, and most patients present with vaginal bleeding. Adults with adenocarcinoma of the cervix or vagina will present with stage I or stage II disease 90% of the time. In children and adolescents, there is a high incidence of stage III and stage IV disease (24%). This difference may be explained by the practice of routine pelvic examinations in adults and the hesitancy to perform pelvic exams in children.

Treatment and Outcome

Treatment options for carcinoma of the cervix and vagina include the following:

1. Surgery.
2. Radiation therapy, for residual microscopic disease or lymphatic metastases.

The treatment of choice is surgical resection,[73] followed by radiation therapy for residual microscopic disease or lymphatic metastases. The role of chemotherapy in management is unknown, although drugs commonly used in the treatment of gynecologic malignancies, carboplatin and paclitaxel, have been used.

The 3-year EFS for all stages is 71% ± 11%; for stage I and stage II, the EFS is 82% ± 11%, and for stage III and stage IV, the EFS is 57% ± 22%.[72]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Clinical Presentation and Diagnostic Evaluation

• Multiple endocrine neoplasia type 1 (MEN1) syndrome (Werner syndrome): MEN1 syndrome is an autosomal dominant disorder characterized by the presence of tumors in the parathyroid, pancreatic islet cells, and anterior pituitary. Diagnosis of this syndrome should be considered when two endocrine tumors listed in Table 6 are present.
  A study documented the initial symptoms of MEN1 syndrome occurring before age 21 years in 160 patients.[3] Of note, most patients had familial MEN1 syndrome and were followed up using an international screening protocol.

  1. Primary hyperparathyroidism. Primary hyperparathyroidism, the most common symptom, was found in 75% of patients, usually only in those with biological abnormalities. Primary hyperparathyroidism diagnosed outside of a screening program is extremely rare, most often presents with nephrolithiasis, and should lead the clinician to suspect MEN1.[3,4]
  2. Pituitary adenomas. Pituitary adenomas were discovered in 34% of patients, occurred mainly in females older than 10 years, and were often symptomatic.[3]
  3. Pancreatic neuroendocrine tumors. Pancreatic neuroendocrine tumors were found in 23% of patients. Specific diagnoses included insulinoma, nonsecreting pancreatic tumor, and Zollinger-Ellison syndrome. The first case of insulinoma occurred before age 5 years.[3]
  4. Malignant tumors. Four patients had malignant tumors (two adrenal carcinomas, one gastrinoma, and one thymic carcinoma). The patient with thymic carcinoma died before age 21 years from rapidly progressive disease.
  Germline mutations of the MEN1 gene located on chromosome 11q13 are found in 70% to 90% of patients; however, this gene has also been shown to be frequently inactivated in sporadic tumors.[5] Mutation testing is combined with clinical screening for patients and family members with proven at-risk MEN1 syndrome.[6]
  It is recommended that screening for patients with MEN1 syndrome begin by the age of 5 years and continue for life. The number of tests or biochemical screening is age specific and may include yearly serum calcium, parathyroid hormone, gastrin, glucagon, secretin, proinsulin, chromogranin A, prolactin, and IGF-1. Radiologic screening should include a magnetic resonance imaging of the brain and computed tomography of the abdomen every 1 to 3 years.[7]
• Multiple endocrine neoplasia type 2A (MEN2A) and multiple endocrine neoplasia type 2B (MEN2B) syndromes:
  A germline activating mutation in the RET oncogene (a receptor tyrosine kinase) on chromosome 10q11.2 is responsible for the uncontrolled growth of cells in medullary thyroid carcinoma associated with MEN2A and MEN2B syndromes.[8-10] Table 7 describes the clinical features of MEN2A and MEN2B syndromes.

  -

  MEN2A: MEN2A is characterized by the presence of two or more endocrine tumors (refer to Table 6) in an individual or in close relatives.[11] RET mutations in these patients are usually confined to exons 10 and 11.

  -

  MEN2B: MEN2B is characterized by medullary thyroid carcinomas, parathyroid hyperplasias, adenomas, pheochromocytomas, mucosal neuromas, and ganglioneuromas.[11-13] The medullary thyroid carcinomas that develop in these patients are extremely aggressive. More than 95% of mutations in these patients are confined to codon 918 in exon 16, causing receptor autophosphorylation and activation.[14] Patients also have medullated corneal nerve fibers, distinctive faces with enlarged lips, and an asthenic Marfanoid body habitus.

  A pentagastrin stimulation test can be used to detect the presence of medullary thyroid carcinoma in these patients, although management of patients is driven primarily by the results of genetic analysis for RET mutations.[14,15]

  Guidelines for genetic testing of suspected patients with MEN2 syndrome and the correlations between the type of mutation and the risk levels of aggressiveness of medullary thyroid cancer have been published.[15,16]
• Familial Medullary Thyroid Carcinoma: Familial medullary thyroid carcinoma is diagnosed in families with medullary thyroid carcinoma in the absence of pheochromocytoma or parathyroid adenoma/hyperplasia. RET mutations in exons 10, 11, 13, and 14 account for most cases.
  The most-recent literature suggests that this entity should not be identified as a form of hereditary medullary thyroid carcinoma that is separate from MEN2A and MEN2B. Familial medullary thyroid carcinoma should be recognized as a variant of MEN2A, to include families with only medullary thyroid cancer who meet the original criteria for familial disease. The original criteria includes families of at least two generations with at least two, but less than ten, patients with RET germline mutations; small families in which two or fewer members in a single generation have germline RET mutations; and single individuals with a RET germline mutation.[15,17]

Treatment

Treament options for MEN syndrome, according to type, are as follows:

1. MEN1 syndrome: Treatment of patients with MEN1 syndrome is based on the type of tumor. The outcome of patients with MEN1 syndrome is generally good provided adequate treatment can be obtained for parathyroid, pancreatic, and pituitary tumors.
   The standard approach to patients who present with hyperparathyroidism and MEN1 syndrome is genetic testing and treatment with a cervical resection of at least three parathyroid glands and transcervical thymectomy.[4]
2. MEN2 syndromes: The management of medullary thyroid cancer in children from families having MEN2 syndromes relies on presymptomatic detection of the RET proto-oncogene mutation responsible for the disease.

   • MEN2A syndrome: For children with MEN2A, thyroidectomy is commonly performed by approximately age 5 years or older if that is when a mutation is identified.[10,18-22] The outcome for patients with MEN2A syndrome is also generally good, yet the possibility exists for recurrence of medullary thyroid carcinoma and pheochromocytoma.[23-25] A retrospective analysis identified 262 patients with MEN2A syndrome.[26] Median age of the cohort was 42 years and ranged from age 6 to 86 years. There was no correlation between the specific RET mutation identified and the risk of distant metastasis. Younger age at diagnosis did increase the risk of distant metastasis.
     Relatives of patients with MEN2A undergo genetic testing in early childhood, before the age of 5 years. Carriers undergo total thyroidectomy as described above with autotransplantation of one parathyroid gland by a certain age.[22,27-29]
   • MEN2B syndrome: Because of the increased virulence of medullary thyroid carcinoma in children with MEN2B and in those with mutations in codons 883, 918, and 922, it is recommended that these children undergo prophylactic thyroidectomy in infancy.[14,19,30]; [31][Level of evidence: 3iiiDii] Patients who have MEN2B syndrome have a worse outcome primarily because of more aggressive medullary thyroid carcinoma. Prophylactic thyroidectomy has the potential to improve the outcome in MEN2B.[32]
   Complete removal of the thyroid gland is the recommended procedure for surgical management of medullary thyroid cancer in children because there is a high incidence of bilateral disease.
   Hirschsprung disease has been associated in a small percentage of cases with the development of neuroendocrine tumors such as medullary thyroid carcinoma. RET germline inactivating mutations have been detected in up to 50% of patients with familial Hirschsprung disease and less often in the sporadic form.[33-35] Cosegregation of Hirschsprung disease and medullary thyroid carcinoma phenotype is infrequently reported, but these individuals usually have a mutation in RET exon 10. Patients with Hirschsprung disease are screened for mutations in RET exon 10; if such a mutation is discovered, a prophylactic thyroidectomy should be considered.[35-37]
   (Refer to the PDQ summary on Genetics of Endocrine and Neuroendocrine Neoplasias for more information about MEN2A and MEN2B.)

In a randomized phase III trial for adult patients with unresectable locally advanced or metastatic hereditary or sporadic medullary thyroid carcinoma treated with either vandetanib (a selective inhibitor of RET, vascular endothelial growth factor receptor, and epidermal growth factor receptor) or placebo, vandetanib administration was associated with significant improvements in progression-free survival, response rate, disease control rates, and biochemical response.[38] Children with locally advanced or metastatic medullary thyroid carcinoma were treated with vandetanib in a phase I/II trial. Of 16 patients, only one had no response and seven had a partial response. Disease in three of those patients subsequently recurred, but 11 of 16 patients treated with vandetanib remained on therapy at the time of the report.[39]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Carney Complex

Carney complex is an autosomal dominant syndrome caused by mutations in the PPKAR1A gene, located in chromosome 17.[40] The syndrome is characterized by cardiac and cutaneous myxomas, pale brown to brown lentigines, blue nevi, primary pigmented nodular adrenocortical disease causing Cushing syndrome, and a variety of endocrine and nonendocrine tumors, including pituitary adenomas, thyroid tumors, and large cell calcifying Sertoli cell tumor of the testis.[40-42] There are published surveillance guidelines for patients with Carney complex that include cardiac, testicular, and thyroid ultrasound.

For patients with the Carney complex, prognosis depends on the frequency of recurrences of cardiac and skin myxomas and other tumors.

Incidence

Pheochromocytoma and paraganglioma are rare catecholamine-producing tumors with a combined annual incidence of three cases per 1 million individuals. Paraganglioma and pheochromocytoma are exceedingly rare in the pediatric and adolescent population, accounting for approximately 20% of all cases.[43,44]

Anatomy

Tumors arising within the adrenal gland are known as pheochromocytomas, whereas morphologically identical tumors arising elsewhere are termed paragangliomas. Paragangliomas are further divided into the following subtypes:[45,46]

• Sympathetic paragangliomas that predominantly arise from the intra-abdominal sympathetic trunk and usually produce catecholamines.
• Parasympathetic paragangliomas that are distributed along the parasympathetic nerves of the head, neck, and mediastinum and are rarely functional.

Genetic Factors and Syndromes Associated with Pheochromocytoma and Paraganglioma

It is now estimated that up to 30% of all pheochromocytomas and paragangliomas are familial; several susceptibility genes have been described (refer to Table 8). The median age at presentation in most familial syndromes is 30 to 35 years, and up to 50% of subjects have disease by age 26 years.[47-50]

Genetic factors and syndromes associated with an increased risk of pheochromocytoma and paraganglioma include the following:

1. von Hippel-Lindau (VHL) syndrome: Pheochromocytoma and paraganglioma occur in 10% to 20% of patients with VHL.
2. Multiple Endocrine Neoplasia (MEN) Syndrome Type 2: Codon-specific mutations of the RET gene are associated with a 50% risk of development of pheochromocytoma in MEN2A and MEN2B. Somatic RET mutations are also found in sporadic pheochromocytoma and paraganglioma.
3. Neurofibromatosis type 1 (NF1): Pheochromocytoma and paraganglioma are a rare occurrence in patients with NF1, and typically have characteristics similar to those of sporadic tumors, with a relatively late mean age of onset and rarity in pediatrics.
4. Familial pheochromocytoma/paraganglioma syndromes, associated with germline mutations of mitochondrial succinate dehydrogenase (SDH) complex genes (refer to Table 8). They are all inherited in an autosomal dominant manner but with varying penetrance.

   • PGL1: Associated with SDHD mutations, manifests more commonly with head and neck paragangliomas, and has a very high penetrance, with more than 80% of carriers developing disease by age 50 years.
   • PGL2: Associated with SDHAF2 mutations, is very rare, and generally manifests as parasympathetic paraganglioma.
   • PGL3: Associated with SDHC mutations, is very rare, and usually presents with parasympathetic paraganglioma, often unifocal, benign, and in the head and neck.
   • PGL4: Associated with SDHB mutations and usually manifests with intra-abdominal sympathetic paraganglioma. The neoplasms associated with this mutation have a much higher risk of malignant behavior, with more than 50% of patients developing metastatic disease. There is also an increased risk of renal cell carcinoma and gastrointestinal stromal tumor (GIST).
   (Refer to the Familial Pheochromocytoma and Paraganglioma Syndrome section in the PDQ summary on Genetics of Endocrine and Neuroendocrine Neoplasias for more information.)
5. Other syndromes:

   • Carney triad syndrome. Carney triad syndrome is a condition that includes three tumors: paraganglioma, GIST, and pulmonary chondromas. Pheochromocytomas and other lesions such as esophageal leiomyomas and adrenocortical adenomas have also been described. The syndrome primarily affects young women, with a mean age of 21 years at time of presentation. Approximately one-half of the patients present with paraganglioma or pheochromocytoma, although multiple lesions occur in approximately 20% of the cases. About 20% of the patients have all three tumor types; the remainder have two of the three, most commonly GIST and pulmonary chondromas. This triad doesn’t appear to run in families; however, approximately 10% of the patients have germline variants in the SDHA, SDHB or SDHC genes.[51,52]
   • Carney-Stratakis syndrome. Carney-Stratakis syndrome (Carney dyad syndrome) is a condition that includes paraganglioma and GIST, but not pulmonary chondromas. It is inherited in an autosomal dominant manner with incomplete penetrance. It is equally common in men and women, with an average age of 23 years at presentation. Most patients with this syndrome have been found to carry germline mutations in the SDHB, SDHC, or SDHD genes.[52]
6. Other susceptibility genes recently discovered include KIF1B-beta, EGLN1/PHD2, TMEM127, SDHA, and MAX.[50]

These susceptibility genes can be divided into the following cluster groups on the basis of transcriptomic profiles:[53,54]

• Cluster 1: Resulting from mutations in genes encoding the VHL suppressor, the four subunits of SDH complex (SDHA, SDHB, SDHC, and SDHD), SDHAF2, and other less frequent enzymes.
• Cluster 2: Resulting from mutations in NF1, RET, TMEM127, and MAX.

Molecular Features

Studies of germline mutations in young patients with pheochromocytoma or paraganglioma have shown that these patients have a higher prevalence (70%–80%) of germline mutations and have further characterized this group of neoplasms, as follows:

1. In a study of 49 patients younger than 20 years with a paraganglioma or pheochromocytoma, 39 (79%) had an underlying germline mutation that involved the SDHB (n = 27; 55%), SDHD (n = 4; 8%), VHL (n = 6; 12%), or NF1 (n = 2; 4%) gene.[44] The incidence and type of mutation correlated with the site and extent of disease.

   • The germline mutation rates for patients with nonmetastatic disease were lower than those observed in patients who had evidence of metastases (64% vs. 87.5%).
   • Among patients with metastatic disease, the incidence of SDHB mutations was very high (72%) and most presented with disease in the retroperitoneum; five died of their disease.
   • All patients with SDHD mutations had head and neck primary tumors.
2. In another study, the incidence of germline mutations involving RET, VHL, SDHD and SDHB in patients with nonsyndromic paraganglioma was 70% for patients younger than 10 years and 51% among those aged 10 to 20 years.[55] In contrast, only 16% of patients older than 20 years had an identifiable mutation.[55]
   It is important to note that these two studies did not include systematic screening for other genes that have been recently described in paraganglioma and pheochromocytoma syndromes, such as KIF1B-beta, EGLN1/PHD2, TMEM127, SDHA, and MAX (refer to Table 8).
3. In a retrospective review of 55 patients younger than 21 years referred to the National Cancer Institute, 80% of patients had a germline mutation.[56]

   • Most patients were found to have either the VHL (38%) or the SDHB (25%) mutation. Pheochromocytoma was present in 67% of the patients (37 of 55) and was bilateral in 51% of patients (19 of 37).
   • Most patients with bilateral pheochromocytomas had VHL mutations (79%).
4. A retrospective analysis from the European-American-Pheochromocytoma-Paraganglioma-Registry identified 177 patients with paraganglial tumors who were diagnosed before age 18 years.[57][Level of evidence: 3iiA]

   • Eighty percent of registrants had germline mutations (49% with VHL, 15% with SDHB, 10% with SDHD, 4% with NF1, and one patient each with RET, SDHA, and SDHC).
   • A second primary paraganglial tumor developed in 38% of patients, with increasing frequency over time, reaching 50% at 30 years from initial presentation.
   • Prevalence of second tumors was higher in patients with hereditary disease. Sixteen patients (9%) with hereditary disease had malignant tumors, ten at initial presentation and another six during follow-up. Malignancy was associated with SDHB mutations. Eight patients (5%) died, all of whom had a germline mutation. Mean life expectancy was 62 years for patients with hereditary disease.
5. A large retrospective review from tertiary medical centers identified 95 of 748 patients whose tumor first presented in childhood.[58]

   • Children showed higher prevalence of hereditary (80.4% vs. 52.6%), extra-adrenal (66.3% vs. 35.1%), multifocal (32.6% vs. 13.5%), metastatic (49.5% vs. 29.1%), and recurrent (29.5% vs. 14.2%) pheochromocytoma or paraganglioma than did adults.
   • Tumors caused by cluster 1 mutations, which are associated with the absence of epinephrine production, were more prevalent among children than adults (76% vs. 39%; P < .0001), and this paralleled a higher prevalence of noradrenergic tumors, characterized by relative lack of increased plasma metanephrine, in children than in adults (93.2% vs. 57.3%).

Immunohistochemical SDHB staining may help triage genetic testing; tumors of patients with SDHB, SDHC, and SDHD mutations have absent or very weak staining, while sporadic tumors and those associated with other constitutional syndromes have positive staining.[59,60] Therefore, immunohistochemical SDHB staining can help identify potential carriers of a SDH mutation early, obviating the need for extensive and costly testing of other genes. Early identification of young patients with SDHB mutations using radiographic, serologic, and immunohistochemical markers could potentially decrease mortality and identify other family members who carry a germline SDHB mutation.

Given the higher prevalence of germline alterations in children and adolescents with pheochromocytoma and paraganglioma, genetic counseling and testing should be considered in this younger population.

Clinical Presentation

Patients with pheochromocytoma and sympathetic extra-adrenal paraganglioma usually present with the following symptoms of excess catecholamine production:

• Hypertension.
• Headache.
• Perspiration.
• Palpitations.
• Tremor.
• Facial pallor.

These symptoms are often paroxysmal, although sustained hypertension between paroxysmal episodes occurs in more than one-half of patients. These symptoms can also be induced by exertion, trauma, induction of anesthesia, resection of the tumor, consumption of foods high in tyramine (e.g., red wine, chocolate, cheese), or urination (in cases of primary tumor of the bladder).[45]

Parasympathetic extra-adrenal paragangliomas do not secrete catecholamines and usually present as a neck mass with symptoms related to compression, but also may be asymptomatic and diagnosed incidentally.[45] Epinephrine production is also associated with cluster genotype. Cluster 1 tumors are characterized by absence of epinephrine production (noradrenergic phenotype), whereas cluster 2 tumors produce epinephrine (adrenergic phenotype).[58]

The pediatric and adolescent patient appears to present with symptoms similar to those of the adult patient, although with a more frequent occurrence of sustained hypertension.[61] The clinical behavior of paraganglioma and pheochromocytoma appears to be more aggressive in children and adolescents and metastatic rates of up to 50% have been reported.[44,46,61] As previously discussed, children and adolescents with pheochromocytoma and paraganglioma have a higher prevalence of hereditary, extra-adrenal, multifocal, metastatic, and recurrent pheochromocytomas and paragangliomas; they also have a higher prevalence of cluster 1 mutations, which is paralleled by a higher prevalence of noradrenergic tumors than in adults.[58]

Diagnostic Evaluation

The diagnosis of paraganglioma and pheochromocytoma relies on the biochemical documentation of excess catecholamine secretion coupled with imaging studies for localization and staging:

• Biochemical testing: Measurement of plasma-free fractionated metanephrines (metanephrine and normetanephrine) is usually the diagnostic tool of choice when the diagnosis of a secreting paraganglioma or pheochromocytoma is suspected. A 24-hour urine collection for catecholamines (epinephrine, norepinephrine, and dopamine) and fractionated metanephrines can also be performed for confirmation.[62,63]
  Catecholamine metabolic and secretory profiles are impacted by hereditary background; both hereditary and sporadic paraganglioma and pheochromocytoma differ markedly in tumor contents of catecholamines and corresponding plasma and urinary hormonal profiles. About 50% of secreting tumors produce and contain a mixture of norepinephrine and epinephrine, while most of the rest produce norepinephrine almost exclusively, with occasional rare tumors producing mainly dopamine. Patients with epinephrine-producing tumors are diagnosed later (median age, 50 years) than those with tumors lacking appreciable epinephrine production (median age, 40 years). Patients with MEN2 and NF1 syndromes, all with epinephrine-producing tumors, are typically diagnosed at a later age (median age, 40 years) than are patients with tumors that lack appreciable epinephrine production secondary to mutations of VHL and SDH (median age, 30 years). These variations in ages at diagnosis associated with different tumor catecholamine phenotypes and locations suggest origins of paraganglioma and pheochromocytoma for different progenitor cells with variable susceptibility to disease-causing mutations.[64,65]
• Imaging: Imaging modalities available for the localization of paraganglioma and pheochromocytoma include the following:

  -

  Computed tomography (CT).

  -

  Magnetic resonance imaging.

  -

  Iodine I 123 or iodine I 131-labeled metaiodobenzylguanidine (123/131I-MIBG) scintigraphy.

  -

  Fluorine F 18-6-fluorodopamine (18F-6F-FDA) positron emission tomography (PET).

  For tumor localization, 18F-6F-FDA PET and 123/131I-MIBG scintigraphy perform equally well in patients with nonmetastatic paraganglioma and pheochromocytoma, but metastases are better detected by 18F-6F-FDA PET than by 123/131I-MIBG.[66,67] Other functional imaging alternatives include indium In 111-octreotide scintigraphy and fluorine F 18-fludeoxyglucose PET, both of which can be coupled with CT imaging for improved anatomic detail.

Treatment

Treatment of paraganglioma and pheochromocytoma is surgical. For secreting tumors, alpha- and beta-adrenergic blockade must be optimized before surgery.

For patients with metastatic disease, responses have been documented to some chemotherapeutic regimens such as gemcitabine and docetaxel or different combinations of vincristine, cyclophosphamide, doxorubicin, and dacarbazine.[68-70] Chemotherapy may help alleviate symptoms and facilitate surgery, although its impact on overall survival (OS) is less clear.

Responses have also been obtained to high-dose 131I-MIBG and sunitinib.[71,72]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following are examples of national and/or institutional clinical trials that are currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).
• NCT02961491 (Expanded Access Program of Ultratrace Iobenguane I 131 for Malignant Relapsed/Refractory Pheochromocytoma/Paraganglioma): The purpose of this study is to provide expanded access to iobenguane I 131 for newly enrolled subjects with iobenguane-avid metastatic and/or recurrent pheochromocytoma/paraganglioma and to collect additional safety data.
• NCT01163383 (131I-MIBG Therapy for Refractory Neuroblastoma and Metastatic Paraganglioma/Pheochromocytoma): MIBG is a substance that is taken up by neuroblastoma or pheochromocytoma/paraganglioma tumor cells. MIBG is combined with radioactive iodine (131I) in the laboratory to form a radioactive compound, 131I-MIBG. This radioactive compound delivers radiation specifically to the cancer cells, causing them to die. The purpose of this research protocol is to provide a mechanism to deliver MIBG therapy when clinically indicated, but also to provide a mechanism to continue to collect efficacy and toxicity data that will be provided.
• NCT03165721 (A Phase II Trial of the DNA Methyl Transferase Inhibitor, Guadecitabine [SGI-110], in Children and Adults With Wild-Type GIST, Pheochromocytoma and Paraganglioma Associated With Succinate Dehydrogenase Deficiency and HLRCC-associated Kidney Cancer): Most people with GIST are treated with imatinib; however, it may not work in many children with GIST. Researchers hypothesize that the drug SGI-110 may help treat people with GIST, pheochromocytoma and paraganglioma, or kidney cancer related to hereditary leiomyomatosis and renal cell carcinoma. The objective of this trial is to determine whether SGI-110 shrinks tumors or slows tumor growth and to test how it acts in the body.

Melanoma

BCC and SCC

Incidence and Risk Factors

Uveal melanoma (iris, ciliary body, choroid) is the most common primary intraocular malignancy (about 2,000 cases are diagnosed each year in the United States) and accounts for 5% of all cases of melanoma.[157] This tumor is most commonly diagnosed in older patients, and the incidence peaks at age 70 years.[158]

Pediatric uveal melanoma is extremely rare and accounts for 0.8% to 1.1% of all cases of uveal melanoma.[159] A retrospective, multicenter, observational study conducted by the European Ophthalmic Oncology Group from 1968 to 2014 identified 114 children (aged 1–17 years) and 185 young adults (aged 18–25 years) with ocular melanoma at 24 centers.[159] The median age at the time of diagnosis for children was 15.1 years. The incidence of disease increased by 0.8% per year between the ages of 5 and 10 years and 8.8% per year between the ages of 17 and 24 years. Other series have also documented the higher incidence of the disease in adolescents.[160,161]

Risk factors include the following:[162-164]

• Light eye color.
• Fair skin color.
• Inability to tan.
• Oculodermal melanocytosis.
• Presence of cutaneous nevi.

In a European Oncology Group study, 57% of children were females and four had a preexisting condition that included oculodermal melanocytosis (n = 2) and neurofibromatosis (n = 2).[159] In a review of 13 cases of uveal melanoma in the first 2 years of life, four patients had familial atypical melanoma mole syndrome, one patient had dysplastic nevus syndrome, and one patient had café au lait spots.[165]

Molecular Features

Uveal melanoma is characterized by activating mutations of GNAQ and GNA11, which lead to activation of the mitogen-activated protein kinases pathway (MAPK). In addition, mutations in BAP1 are seen in 84% of metastasizing tumors, whereas mutations in SF3B1 and EIF1AX are associated with a good prognosis.[166-171]

Treatment and Outcome

Treatment options for intraocular (uveal) melanoma include the following:

1. Surgery.
2. Radiation therapy.
3. Laser surgery.

(Refer to the PDQ summary on Intraocular [Uveal] Melanoma Treatment for information on the treatment of uveal melanoma in adults.)

Survival of children appears to be more favorable than that of young adults and adults, suggesting that the biology of ocular melanoma might be different in children.[159,160]

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence

Chordoma is a very rare tumor of bone that arises from remnants of the notochord within the clivus, spinal vertebrae, or sacrum; the most common site in children is the cranium.[172] The incidence in the United States is approximately one case per one million people per year, and only 5% of all chordomas occur in patients younger than 20 years.[173,174] Most pediatric patients have the classical or chondroid variant of chordoma, while the dedifferentiated variant is rare in children.[173,175]

Prognosis

Younger children appear to have a worse outlook than do older patients.[173,176-180] The survival rate in children and adolescents ranges from about 50% to 80% for cranial chordomas.[173,177,179] A retrospective literature review and review of institutional patients identified 682 patients with chordomas of the spine, with a median age of 57 years.[181][Level of evidence: 3iiiA] Age younger than 18 years, location in sacral spine, dedifferentiated pathology, and chemotherapy were associated with a lower probability for progression-free survival (PFS). Young age (<18 years), old age (>65 years), bladder or bowel dysfunction at presentation, dedifferentiated pathology, recurrence or progression, and metastases were associated with a worse overall survival. Histopathology is also an important prognostic factor, with atypical or chondroid pathology having worse outcomes than classical pathology.[182][Level of evidence: 3iiiA]

A retrospective analysis identified seven children with poorly differentiated chordomas.[183][Level of evidence: 3iiA] The median survival of these patients was 9 months. All poorly differentiated chordomas showed loss of SMARCB1 expression by immunohistochemistry. Copy number profiles were derived from intensity measures of the methylation probes and indicated 22q losses affecting the SMARCB1 region in all poorly differentiated chordomas.

Clinical Presentation

Patients usually present with pain, with or without neurologic deficits such as cranial or other nerve impairment. Diagnosis is straightforward when the typical physaliferous (soap-bubble-bearing) cells are present. Differential diagnosis is sometimes difficult and includes dedifferentiated chordoma and chondrosarcoma. Childhood chordoma has been associated with tuberous sclerosis complex.[184]

Treatment

Treatment options for chordoma include the following:

1. Surgery.
2. Radiation therapy.

Standard treatment includes surgery and external radiation therapy, often proton-beam radiation.[179,185] Surgery is not commonly curative in children and adolescents because of difficulty obtaining clear margins and the likelihood of the chordoma arising in the skull base, rather than in the sacrum, making them relatively inaccessible to complete surgical excision. However, if gross-total resection can be achieved, outcome is improved.[186][Level of evidence: 3iiA]

The best results have been obtained using proton-beam therapy (charged-particle radiation therapy) because these tumors are relatively radiation resistant, and radiation-dose conformality with protons allows for higher tumor doses while sparing adjacent critical normal tissues.[187,188]; [179,189][Level of evidence: 3iiA]; [190][Level of evidence: 3iiiDiii]

There are only a few anecdotal reports of the use of cytotoxic chemotherapy after surgery alone or surgery plus radiation therapy. Treatment with ifosfamide/etoposide and vincristine/doxorubicin/cyclophosphamide has been reported with some success.[191,192] The role for chemotherapy in the treatment of this disease is uncertain.

Imatinib mesylate has been studied in adults with chordoma on the basis of the overexpression of PDGFR alpha, beta, and KIT in this disease.[193,194] Among 50 adults with chordoma treated with imatinib and evaluable by Response Evaluation Criteria In Solid Tumors (RECIST) guidelines, there was one partial response and 28 additional patients had stable disease at 6 months.[194] The low rate of RECIST responses and the potentially slow natural course of the disease complicate the assessment of the efficacy of imatinib for chordoma.[194] Other tyrosine kinase inhibitors and combinations involving kinase inhibitors have been studied in adults.[195-197] One multicenter French retrospective study reported five patients who had partial responses to treatment with either imatinib, sorafenib, or erlotinib, with a median PFS of 36 months.[198]

Recurrences are usually local but can include distant metastases to lungs or bone.

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Patients with chordomas and SMARCB1 mutations may be offered treatment with tazemetostat on the APEC1621C (NCT03213665) treatment arm of this trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).

Incidence and Clinical Presentation

Children represent less than 1% of all solid cancers of unknown primary site and because of the age-related incidence of tumor types, embryonal histologies are more common in this age group.[199]

Cancers of unknown primary site present as a metastatic cancer for which a precise primary tumor site cannot be determined.[200] As an example, lymph nodes at the base of the skull may enlarge in relationship to a tumor that may be on the face or the scalp but is not evident by physical examination or by radiographic imaging. Thus, modern imaging techniques may indicate the extent of the disease but not a primary site. Tumors such as adenocarcinomas, melanomas, and embryonal tumors such as rhabdomyosarcomas and neuroblastomas may present in this way.

Diagnostic Evaluation

For all patients who present with tumors from an unknown primary site, treatment is directed toward the specific histopathology of the tumor and is age-appropriate for the general type of cancer initiated, irrespective of the site or sites of involvement.[200]

Studies in adults suggest that PET imaging can be helpful in identifying cancers of unknown primary site, particularly in patients whose tumors arise in the head and neck area.[201] A report in adults using fluorine F 18-fludeoxyglucose (18F-FDG) PET-CT identified 42.5% of primary tumors in a group of cancers of unknown primary site.[202]

The use of gene expression profiling and next-generation sequencing can enhance the ability to identify the putative tissue of origin and guide in the selection of targeted agents for specific mutations.[203- 207] No pediatric studies have been conducted to date.

Treatment

Chemotherapy, targeted therapy, and radiation therapy treatments appropriate and relevant for the general category of carcinoma or sarcoma (depending on the histologic findings, symptoms, and extent of tumor) are initiated as early as possible.[208]

(Refer to the PDQ summary on adult Carcinoma of Unknown Primary Treatment for more information.)

Treatment Options Under Clinical Evaluation

Information about National Cancer Institute (NCI)–supported clinical trials can be found on the NCI website. For information about clinical trials sponsored by other organizations, refer to the ClinicalTrials.gov website.

The following is an example of a national and/or institutional clinical trial that is currently being conducted:

• APEC1621 (NCT03155620) (Pediatric MATCH: Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients with Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders): NCI-COG Pediatric Molecular Analysis for Therapeutic Choice (MATCH), referred to as Pediatric MATCH, will match targeted agents with specific molecular changes identified using a next-generation sequencing targeted assay of more than 3,000 different mutations across more than 160 genes in refractory and recurrent solid tumors. Children and adolescents aged 1 to 21 years are eligible for the trial.
  Tumor tissue from progressive or recurrent disease must be available for molecular characterization. Patients with tumors that have molecular variants addressed by treatment arms included in the trial will be offered treatment on Pediatric MATCH. Additional information can be obtained on the ClinicalTrials.gov website for APEC1621 (NCT03155620).