Endoscopic full-thickness resection of well-differentiated T2 neuroendocrine tumors in the duodenal bulb: a case series.

Background and Aims: Endoscopic therapies have moved to the forefront in the removal of small, well-differentiated duodenal neuroendocrine tumors (NETs). Classic procedures used to address small tumors, especially those less than 1 cm in diameter, are banding without resection, ligation endoscopic mucosal resection, or endoscopic submucosal dissection. Endoscopic full-thickness resection (EFTR) is a procedure developed recently that allows for sealing off of the tissue surrounding the tumor before full-thickness removal. Although surgical resection is typically recommended for NETs measuring 2 cm and larger, this may not always be possible given patients' ages or comorbidities. We present the cases of 3 patients with well-differentiated NETs of the duodenal bulb measuring greater than 2 cm who were poor candidates for surgery and were thus offered EFTR for excision of their tumors. Methods: Three patients with well-differentiated, stage II NETs of the duodenal bulb underwent chromoendoscopy and narrow-band imaging, EUS, prophylactic dilation of the upper esophageal sphincter and pylorus, and EFTR using an over-the-scope clip system. Results: In each case, there was no residual mass seen on endoscopy, Ga-68 Dotatate positron emission tomography-CT imaging, or biopsy up to 1 year after the procedure. Two of the 3 cases had normal chromogranin A levels at all follow-up points, and the third case had chromogranin A levels that trended down to a near-normal level of 145 ng/mL. Conclusions: Three patients with NETs of the duodenal bulb who were poor surgical candidates underwent successful EFTR using a full-thickness resection device. At 1-year follow-up, they have no evidence of disease recurrence on imaging and pathology after EFTR.