Recent updates on the endoscopic treatment of rectal neuroendocrine tumor.

The incidence of rectal neuroendocrine tumors has been gradually increasing, primarily due to the widespread use of screening colonoscopy and growing awareness of the disease. Most rectal neuroendocrine tumors are small ( < 10 mm), well-differentiated, and low-grade lesions at the time of diagnosis, and they are usually asymptomatic. Given these characteristics, endoscopic resection is considered a feasible treatment option for early-stage lesions. However, due to their inherent malignant potential, a comprehensive initial diagnostic evaluation is essential. Lymph node or distal metastasis can be present at diagnosis or may develop long after apparently successful primary treatment. Therefore, achieving complete resection using the most optimal resection method is crucial. Modified endoscopic mucosal resection and endoscopic submucosal dissection are recommended over conventional forceps or snare polypectomy, which are associated with high incomplete resection rates. In case of incomplete resection, additional endoscopic resection can be a feasible option in selected cases. Furthermore, regular post-resection surveillance is needed, especially in patients with high-risk of recurrence such as poor pathologic result or incomplete resection.