Pheochromocytoma/paraganglioma syndrome-1 (PPGL1) is an autosomal dominant disorder characterized by the development of neuroendocrine tumors, usually in adulthood. Pheochromocytomas arise from chromaffin cells in the adrenal medulla, whereas paragangliomas arise in extra-adrenal sympathetic ganglia in the thorax, abdomen, and pelvis or from parasympathetic paraganglia in the head and neck area (summary by Cascon et al., 2023).
Paragangliomas, also referred to as 'glomus body tumors,' are tumors derived from paraganglia located throughout the body. Nonchromaffin types primarily serve as chemoreceptors (hence, the tumor name 'chemodectomas') and are located in the head and neck region (i.e., carotid body, jugular, vagal, and tympanic regions), whereas chromaffin types have endocrine activity, conventionally referred to as 'pheochromocytomas,' and are usually located below the head and neck (i.e., adrenal medulla and pre- and paravertebral thoracoabdominal regions). PPGL can manifest as nonchromaffin head and neck tumors only, adrenal and/or extraadrenal pheochromocytomas only, or a combination of the 2 types of tumors (Baysal, 2002; Neumann et al., 2004).
The triad of gastric leiomyosarcoma, pulmonary chondroma, and extraadrenal paraganglioma constitutes a syndrome that occurs mainly in young women and is known as the Carney triad (604287). This triad is not to be confused with the other Carney syndrome of myxoma, spotty pigmentation, and endocrinopathy (160980).
Baysal (2008) provided a review of the molecular pathogenesis of hereditary paraganglioma.
Genetic Heterogeneity of Pheochromocytoma/Paraganglioma Syndrome
See also PPGL2 (601650), caused by mutation in the SDHAF2 gene (613019) on chromosome 11q13; PPGL3 (605373), caused by mutation in the SDHC gene (602413) on chromosome 1q21; PPGL4 (115310), caused by mutation in the SDHB gene (185470) on chromosome 1p36; PPGL5 (614165), caused by mutation in the SDHA gene (600857) on chromosome 5p15; PPGL6 (618464), caused by mutation in the SLC25A11 gene (604165) on chromosome 17p13; and PPGL7 (618475), caused by mutation in the DLST gene (126063) on chromosome 14q24. [from
OMIM]