Risk factors of delayed bleeding after endoscopic resection of superficial non-ampullary duodenal epithelial tumors and prevention by over-the-scope and conventional clipping

Objectives This study was aimed to reveal risk factors for delayed bleeding after endoscopic resection (ER) of superficial non-ampullary duodenal epithelial tumors (SNADETs) and at exploring measures to prevent this complication. Methods A total of 235 consecutive patients with 249 SNADETs who had undergone ER were enrolled in this study. They were divided into two groups: OTSC group, consisting of the initial 114 cases in which the defects were closed only using OTSCs; and OTSC-c group, consisting of the later 135 cases in which conventional clips were additionally used to cover the inverted submucosa after post-procedure defect closure using OTSCs. The therapeutic outcomes were then compared between the OTSC and OTSC-c groups. Results All lesions were successfully resecteden-bloc, and the R0 resection rate was 92.4%. The complete defect closure rate was 90.0% and no delayed perforation occurred when successful defect closure was achieved. The rate of delayed bleeding was significantly higher in the OTSC group than in OTSC-c group (11.4% vs. 1.5%,P = 0.001). Multivariate logistic regression analyses revealed that tumor location distal to the ampulla (OR 10.0; 95% CI 1.24-81.0,P = 0.03) and use of a DOAC (OR 8.83; 95% CI 1.13-68.7,P = 0.04) were significant independent predictors of delayed bleeding. Propensity score-matching analysis revealed that additional use of conventional clips was associated with a significantly reduced risk of delayed bleeding (P = 0.003). Conclusions Additional use of conventional clips after prophylactic defect closure using OTSCs appears to be useful to reduce the risk of delayed bleeding after ER of SNADETs. UMIN Clinical Trials (No. 000035478).