LAUSR

BACKGROUND Delayed bleeding is a common adverse event following endoscopic mucosal resection (EMR) of large colorectal polyps. Prophylactic clip closure of the mucosal defect after EMR of ≥20 mm non-pedunculated polyps reduces the incidence of severe delayed bleeding, especially in proximal polyps. AIM Evaluate factors associated with complete prophylactic clip closure of the mucosal defect after EMR of large polyps. METHODS This is a post-hoc analysis of the CLIP STUDY (NCT01936948). All patients randomized to the clip group were included. Main outcome was complete clip closure of the mucosal resection defect. The defect was considered completely closed when there was no remaining visible mucosal defect and clips were <1cm apart. Factors associated with complete closure were evaluated in multivariable analysis. RESULTS 458 patients (age 65, 58% men) with 494 large polyps were included. Complete clip closure of the resection defect was achieved for 338 polyps (68.4%) and was not complete for 156 (31.6%). Factors associated with complete closure in adjusted analysis were smaller polyp size (OR 1.06 for every mm decrease [1.02-1.08]), good access (OR 3.58 [1.94-9.59]), complete submucosal lifting (OR 2.28 [1.36-3.90]), en bloc resection (OR 5.75 [1.48-22.39]), and serrated histology (OR 2.74 [1.35-5.56]). CONCLUSIONS Complete clip closure was not achieved for almost 1 out of 3 resected large non-pedunculated polyps. While stable access and en bloc resection facilitate clip closure, most factors associated with clip closure are not modifiable and highlight the need for alternative closure options and preventative bleeding measures.