Complication risk despite preventive endoscopic measures in patients undergoing endoscopic mucosal resection of large duodenal adenomas

Background Endoscopic mucosal resection (EMR) is the standard treatment of ampullary and nonampullary duodenal adenomas. EMR of large (10-29mm) and giant (>= 30mm) lesions carries a risk of complications such as delayed bleeding and perforation. Prospective data on duodenal EMR are scarce. This study aimed to evaluate the efficacy of endoscopic procedures (clipping and coagulation of visible vessels) to prevent complications after EMR of large and giant lesions. Methods 110 patients with 118 adenomas (29 ampullary and 89 nonampullary) were included prospectively. Results 15 lesions were small (12.7%), 68 were large (57.6%), and 35 were giant (29.7%). Endoscopic prevention of delayed complications was performed in 81.4% (n=96) of all lesions and 94.3% (n=33) of giant lesions. Complete resection was achieved in 111 lesions (94.1%). Complications were 22 delayed bleedings (18.6%), 3 intraprocedural perforations (2.5%), 2 delayed perforations (1.7%), and 1 stricture (0.8%). Major complications were associated with lesions size >= 30mm (28.6% vs. 9.6%; P =0.02) and ampullary adenomas (27.6% vs. 11.2%; P =0.07). All minor bleeding and 75% of major bleeding episodes were treated endoscopically; 25% of major bleedings needed radiologic embolization. Two fatal courses were observed when delayed perforation occurred after EMR of giant lesions. Residual adenoma was detected in 20.4% at first follow-up. Conclusions EMR of giant duodenal neoplasia carries a substantial risk of major complications and recurrences. Resection technique and prevention of delayed complications need to be improved. Further measures should be evaluated in randomized studies.