Primary neuroendocrine tumors of the colon and rectum

Abstract

Background: The nomenclature and staging classification of neuroendocrine tumors (NETs) has changed drastically in the past decade. Objective: To do a critical analysis of management of colorectal NETs in our institution in the light of the new classification. Methods: We retrospectively reviewed the records of consecutive patients operated on with radical intention due to a colorectal NET in the last 15 years. Results: There were 10 patients, median age was 56 years (range 48-76), six of them located near the ileocecal valve, three in the rectum (2 of them polyps) and one polyp in the sigmoid colon. Surgical procedure included four anterior resections and six right colectomy (one with hepatic resection). The median follow up was 78.3 months (range 8-180). Two patients died due to metastatic disease. Conclusion: NETs located near de ileocecal valve were diagnosed usually as a big tumor with obstructing symptoms, while NETs of the rectum and sigmoid colon more frequently were detected as polyps or submucosal lesions. Some low grade TENs may invade the colonic wall and/or have metastasis in the regional lymph nodes and those cases need radical resection and/or adjuvant therapy. Combine the grade (Ki-67 and number and/ or number of mitosis) of 2010 WHO classification with TNM showed prognostic value for classification and staging colorectal NETs with important therapeutic implications.