S2155 Comparison of EMR, ESD, and EFTR for Endoscopic Resection of Duodenal and Rectal Neuroendocrine Tumors

Introduction: Endoscopic resection is recommended for localized duodenal and small rectal neuroendocrine tumors (NET). Endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and endoscopic full-thickness resection (EFTR) using full-thickness resection device (FTRD) have been used with varying success. A direct comparison of these techniques has not been performed thus far. Our aim is to compare clinical outcomes of rectal and duodenal NET resection via EMR, ESD and EFTR with FTRD. Methods: A retrospective multicenter study (9 centers) was performed, including patients >18 years old with diagnosis of duodenal or rectal NET, and have NET resection by EMR, ESD, or EFTR between 2016 and 2025. NET >2 cm and positive lymph nodes or distant metastases where endoscopic resection is not indicated were excluded. Primary outcomes were negative margin rate (NMR) for deep and lateral margins, procedure time, and adverse events. Comparison groups were based on resection type and/or NET location. Statistical analyses were performed with SPSS with P-value < 0.05 indicating statistical significance. Results: Overall, 174 patients with NET (68 duodenal, 106 rectal) were included. Mean age was 57.3 years with 51.7% men. Over 80% of the NET (73.5% duodenum, 84.9% rectum) were <10 mm. EMR was the most common resection method (61.5% all NET, 64.7% duodenum, 59.4% rectum). NMR for lateral and deep margins was significantly higher in the EFTR with FTRD group compared to EMR and ESD (97.9% EFTR vs 69.9% EMR and 52.6% ESD; P < 0.001). ESD for duodenal NET had the lowest NMR for deep margins at 18.2%. Adverse events were not significantly different between the 3 groups. Conclusion: For small (<20 mm) duodenal and rectal NET, EFTR with FTRD offers the best chance of R0 resection due to higher NMR for deep and lateral margins. EFTR with FTRD also has favorable procedure times and similar adverse events compared to EMR and ESD. Prospective comparative studies are needed to validate these findings.