Mo1509 Endoscopic Snare Papillectomy for Ampullary Neuroendocrine Tumors and Other Rare Ampullary Neoplasms: A Case Series With Long Term Follow up Pietro Familiari, Gianluigi Petrone, Mika Matsuoka, Massimiliano Mutignani, Andrea Tringali, Vincenzo Perri, Ivo Boskoski, Paola Cesaro, Cristiano Spada, Guido Rindi, Guido Costamagna Digestive Endoscopy Unit, Universita’ Cattolica del Sacro Cuore, Rome, Italy; Department of Pathology, Universita’ Cattolica del Sacro Cuore, Rome, Italy Background: Adenomas and adenocarcinomas are the most frequent ampullary tumors. Rarely other tumors can involve the papilla of Vater, especially including neuroendocrine tumors (NET), GIST, lipomas, and others. Endoscopic Snare Papillectomy (ESP) is largely used for the management of benign lesions of the papilla of Vater, as an alternative to a more invasive surgery. The role of ESP in the management of early invasive adenocarcinomas and other neoplasms is controversial. Aim of this study is to report the outcomes of ESP in the management of rare tumors of the papilla of Vater, with a long term follow-up Patients & Methods: All the patients who underwent ESP, between 2004 and June 2009, in a single academic endoscopy center, were identified on a prospective database. Patients who were finally diagnosed with an ampullary adenoma or an adenocarcinoma were excluded. The clinical history of the patients was reconstructed from the medical records, the follow-up examinations reports and directly contacting the patients. Results: During the study period, 8 patients (mean age 53.5 years [range 18-72 years]; 4 males) with rare ampullary tumors underwent ESP. In 7 cases the tumor was occasionally found during an endoscopic examination performed for vague abdominal symptoms. One patients, with an history of retroperitoneal tumors (gangliocytic paragangliomas), presented with jaundice, and CT scan showed an enlarged papilla of Vater. Six of eight ESP were performed en-bloc. Early complications occurred in 2 cases and include a delayed bleeding treated by endoscopy and a mild acute pancreatitis. Six patients were eventually diagnosed with a well differentiated NET (including a gangliocytic paraganglioma); 1 with an adenomyoma; 1 with a solitary fibrous tumor. Mean tumor diameter was 12mm (range 8 mm 17 mm). All the tumors were limited to the papilla of Vater. Microvascular invasion was seen at histology in a patient with a well differentiated NET. The margins of the resected specimens (superficial and depth) has been carefully evaluated at histology. In one case margins were undoubtedly clear; in two cases they were likely positive; in 5 cases they were indefinite or undetermined. None of the patients underwent surgery, and they were followed-up for a mean of 28.7 months (range 5-68 months). All the patients are in good clinical conditions, an no recurrences have been observed during the follow-up. Conclusions: ESP can be successfully applied on small well differentiated NET, instead of a more aggressive surgery. Lacking a strong evidence on the long term efficacy of ESP for NET, a close follow up is recommended for these patients. Neuroendocrine tumor of the papilla of Vater. The papilla of Vater and the tumor are captured with a polypectomy snare.