Background: Transanal endoscopic microsurgery (TEM) has been accepted worldwide for the treatment of local rectal lesions. Rare rectal tumors consist of several different types of malignant or benign tumors. Surgical management is considered to be the only curative option. The aim of this study is to investigate the role of TEM in the treatment of rare rectal tumors.
Materials and methods: A total of 147 patients with rare rectal tumors underwent TEM in our center from April 2006 to May 2017. Clinical data were collected and a retrospective accurate database was constructed. Demographic characteristics, operative details, tumor details, complications, and follow-up data were analyzed.
Results: Seventy-eight patients were male. Mean tumor diameter was 1.2 ± 0.7 cm and mean distance from the anal verge was 6.6 ± 2.3 cm. Full-thickness and complete resection with negative margins was achieved in all patients. Complications occurred in 3 patients during surgery and in 20 patients after surgery. Histopathologic results were neuroendocrine tumors in 104 patients; gastrointestinal stromal tumors in 35; melanoma, lymphoma, and leiomyoma each in 2; lipoma, and squamous carcinoma each in 1. One hundred thirty-five patients were followed up for 49.3 ± 33.2 months. Two patients died, 1 had local recurrence and 1 had a rectovaginal fistula 1 month after surgery. No local recurrence or metastasis, or fecal incontinence was observed in the remaining patients.
Conclusion: TEM is an optimal treatment option for selected rare rectal tumors. The complication rate is low and the therapeutic effect is satisfactory.
Keywords: full-thickness excision; gastrointestinal stromal tumors; neuroendocrine tumors; rare rectal tumor; transanal endoscopic microsurgery.