AIM:To determine an appropriate compartmentalization of endoscopic submucosal dissection(ESD)or endoscopic mucosal resection(EMR)for duodenal tumors.METHODS:Forty-six duodenal lesions(excluding papillary lesions)from 44 patients with duodenal tumors treated endoscopically between 2005 and 2013 were divided into the ESD and EMR groups for retrospective comparison and analysis.RESULTS:The mean age was 65±9 years(35-79years).There were 24 lesions from men and 22 from women.The lesions consisted of 6 early cancers,31adenomas and 9 neuroendocrine tumors.Lesion location was the duodenal bulb in 15 cases and the descending part of the duodenum in 31 cases.The most common macroscopic morphology was elevated type in 21 cases(45.6%).Mean tumor diameter was 11.9±9.7 mm(3-60 mm).Treatment procedure was ESD(15 cases)vs EMR(31 cases).The examined parameters in the ESD vs EMR groups were as follows:mean tumor diameter,12.9±14.3 mm(3-60 mm)vs 11.4 ±6.7 mm(4-25 mm);en bloc resection rate,86.7%vs 83.9%;complete resection rate,86.7%vs 74.2%;procedure time,86.5±63.1 min(15-217 min)vs 13.2±17.0 min(2-89 min)(P<0.0001);intraprocedural perforation,3 cases vs none(P=0.0300);delayed perforation,none in either group;postprocedural bleeding,1 case vs none;mean postoperative length of hospitalization,8.2±2.9 d(5-16 d)vs 6.1±2.0 d(2-12 d)(P=0.0067);recurrence,none vs 1 case(occurring at 7 mo postoperatively).CONCLUSION:ESD was associated with a longer procedure time and a higher incidence of intraprocedural perforation;EMR was associated with a lower rate of complete resection. AIM: To determine an appropriate compartmentalization of endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) for duodenal tumors. METHODS: Forty-six duodenal lesions (excluding papillary lesions) from 44 patients with duodenal tumors treated endoscopically between 2005 and 2013 were divided into the ESD and EMR groups for retrospective comparison and analysis. RESULTS: The mean age was 65 ± 9 years (35-79 years). There were 24 lesions from men and 22 from women. These consisted of 6 early cancers, 31 adenomas and 9 neuroendocrine tumors. Lesion location was the duodenal bulb in 15 cases and the descending part of the duodenum in 31 cases (45.6%). The most common macroscopic morphology was elevated type in 21 cases (45.6%). Mean tumor diameter was 11.9 ± 9.7 mm (3 -60 mm) .Treatment procedure was ESD (15 cases) vs EMR (31 cases). The examined parameters in the ESD vs EMR groups were as follows: mean tumor diameter, 12.9 ± 14.3 mm (3-60 mm) vs 11.4 ± 6.7 mm (4-25 mm); en bloc resection rate, 86.7% vs 83 ; Complete resection rate, 86.7% vs 74.2%; procedure time, 86.5 ± 63.1 min (13-217 min) vs 13.2 ± 17.0 min (2-89 min), P <0.0001; intraprocedural perforation, 3 cases vs none of either delayed group, none of either group; postprocedural bleeding, 1 case vs none; mean postoperative length of hospitalization, 8.2 ± 2.9 days (5-16 days) vs 6.1 ± 2.0 days (2-12 days) (P = 0.0067); recurrence, none vs 1 case (occurring at 7 mo postoperatively) .CONCLUSION: ESD was associated with a longer procedure time and a higher incidence of intraprocedural perforation; EMR was associated with a lower rate of complete resection.