Endoscopic resection of a duodenal neuroendocrine tumor

Endoscopic treatment for duodenal neuroendocrine tumors (d-NET) is technically challenging due to the anatomical characteristics of the duodenum, and is associated with a high risk of perforation and a positive vertical margin because of infiltration into the submucosa. We herein present a case of d-NET that was successfully removed by over-the-scope clip (OTSC)-assisted endoscopic resection. OTSC-assisted endoscopic resection is a safe and reliable treatment method that enables deep submucosal resection in a short time without the risk of perforation.