Factors involved in endoscopists’ choice for prophylactic clipping after colorectal endoscopic mucosal resection: a discrete choice experiment

Background: Delayed bleeding (DB) occurs in ∼10% after colorectal EMR. Prophylactic clipping (PC) was reported to significantly decrease DB-rate in proximal lesions ≥2 cm. Objective: Our aim was to determine which predefined variables contribute to using PC in clinical practice. Methods: We performed an international discrete choice experiment (DCE) among ∼500 endoscopists. Relevant variables for PC use were selected by EMR experts: previous DB, anticoagulants, polyp size, morphology, location, intraprocedural bleeding and visible vessel(s). Respondents answered case scenarios with various variable combinations, each time choosing only one scenario for PC, or the ‘none’ option. Part-worth utilities and importance weights were calculated using HB regression. Subsequently, a predictive model was created to calculate the likelihood of endoscopists choosing PC in any given case. Results: The survey was completed by 190 EMR endoscopists from 17 countries. In total, 8% would never use PC, whereas 30.9% never chose the ‘none’ option. All variables except polyp type were significant in decision-making for PC (p <.01). The most important factor was anticoagulant use, accounting for 22.5% in decision-making. Polyps <2 cm were considered eligible for PC by 14% in the presence of high-weighing factors such as anticoagulant use. No significant differences were found between high and low-to-moderately experienced endoscopists. Conclusions: PC after EMR is often considered useful by endoscopists, usually based on risk factors for DB. Anticoagulant use was the most important factor in decision-making for PC, independent of endoscopist experience. Although not considered cost-effective, one in seven endoscopists chose PC for adenomas <2 cm

Clip placement to prevent delayed bleeding after colonic endoscopic mucosal resection (CLIPPER): study protocol for a randomized controlled trial

Background: Endoscopic mucosal resection (EMR) for large colorectal polyps is in most cases the preferred treatment to prevent progression to colorectal carcinoma. The most common complication after EMR is delayed bleeding, occurring in 7% overall and in approximately 10% of polyps ≥ 2 cm in the proximal colon. Previous research has suggested that prophylactic clipping of the mucosal defect after EMR may reduce the incidence of delayed bleeding in polyps with a high bleeding risk. Methods: The CLIPPER trial is a multicenter, parallel-group, single blinded, randomized controlled superiority study. A total of 356 patients undergoing EMR for large (≥ 2 cm) non-pedunculated polyps in the proximal colon will be included and randomized to the clip group or the control group. Prophylactic clipping will be performed in the intervention group to close the resection defect after the EMR with a distance of < 1 cm between the clips. Primary outcome is delayed bleeding within 30 days after EMR. Secondary outcomes are recurrent or residual polyps and clip artifacts during surveillance colonoscopy after 6 months, as well as cost-effectiveness of prophylactic clipping and severity of delayed bleeding. Discussion: The CLIPPER trial is a pragmatic study performed in the Netherlands and is powered to determine the real-time efficacy and cost-effectiveness of prophylactic clipping after EMR of proximal colon polyps ≥ 2 cm in the Netherlands. This study will also generate new data on the achievability of complete closure and the effects of clip placement on scar surveillance after EMR, in order to further promote the debate on the role of prophylactic clipping in everyday clinical practice. Trial registration: ClinicalTrials.gov NCT03309683. Registered on 13 October 2017. Start recruitment: 05 March 2018. Planned completion of recruitment: 31 August 2021