Local resection of small intestine neuroendocrine neoplasms (SI-NEN) : Current principles

Abstract

Neuroendocrine tumors of the small bowel (small intestine neuroendocrine neoplasms, SI-NEN) are the most frequent tumors of the small intestine and approximately 30-40% are still surgically treatable with curative intent at the time of diagnosis. Certain surgical principles must be followed for optimal oncological outcomes and good postoperative quality of life. Based on international guidelines and own experiences, the locoregional surgical treatment of SI-NENs is presented. Locoregional SI-NENs should always be resected if technically feasible, as only this approach can achieve a long-term cure and even small primary tumors (< 10 mm) often already show lymphatic metastasis. The resectability of SI-NENs and their difficulty depend on the extent of lymphatic metastasis, which should be assessed based on preoperative imaging of the extent around the superior mesenteric artery. Currently, the surgical gold standard for SI-NENs is open surgery with bidigital palpation of the entire small intestine followed by primary tumor resection via small bowel segment resection, right hemicolectomy or ileocecal resection and vessel-sparing, and therefore organ-preserving lymphadenectomy (≥ 8lymph nodes). The guidelines consider that laparoscopic or robotic approaches are justified only for early stages of SI-NENs. Guideline-compliant surgical treatment of locoregional SI-NEN enables recurrence-free long-term survival with good quality of life.