Neuroendocrine Tumors of the Appendix, Colon, and Rectum.

Neuroendocrine neoplasms of the colon and rectum are rare, although surgeons are likely to encounter appendiceal neuroendocrine tumors while caring for patients with appendicitis. Surgery remains the primary treatment, provided disease is resectable, although for small rectal lesions endoscopic resection is often sufficient. Metastastic disease has a variety of treatment options. Poorly differentiated neuroendocrine carcinomas continue to have a poor prognosis.