Published online Aug 7, 2018. doi: 10.3748/wjg.v24.i29.3201
Peer-review started: June 1, 2018
First decision: July 4, 2018
Revised: July 9, 2018
Accepted: July 16, 2018
Article in press: July 16, 2018
Published online: August 7, 2018
Processing time: 63 Days and 14.7 Hours
Small intestinal neuroendocrine tumors (SI-NETs) may demonstrate a widely variable clinical behavior but usually it is indolent. In cases with localized disease, locoregional resective surgery (LRS) is generally indicated with a curative intent. LRS of SI-NETs is also the recommended treatment when symptoms are present, regardless of the disease stage. Concerning asymptomatic patients with distant metastases, prophylactic LRS has been traditionally suggested to avoid possible future complications. Even the current European Neuroendocrine Tumor Society guidelines emphasize a possible effect of LRS in Stage IV SI-NETs with unresectable liver metastases. On the contrary, the 2017 National Comprehensive Cancer Network Guidelines on carcinoid tumors do not support the resection of a small, asymptomatic, relatively stable primary tumor in the presence of unresectable metastatic disease. Furthermore, a recent study revealed no survival advantage for asymptomatic patients with distant-stage disease who underwent upfront LRS. At the aforementioned paper, it was suggested that delayed surgery as needed was comparable with the upfront surgical approach in terms of postoperative morbidity and mortality, the length of the hospital stay and the rate of incisional hernia repairs but was associated with fewer reoperations for bowel obstruction. On the other hand, it is also important to note that some patients might benefit from a prophylactic surgical approach and our attention should focus on identifying this patient population.
Core tip: Upfront locoregional resective surgery of small intestinal neuroendocrine tumors is the mainstay treatment when radical resection is feasible or when symptoms are present, regardless of the disease stage. However, in the light of contemporary evidence, the traditional upfront surgical approach is challenged regarding patients with distant metastases without local tumor-related symptoms.