Two vs one forward view examination of right colon on adenoma detection: an international multicenter randomized trial.

BACKGROUND AND AIMS Second forward view (SFV) examination of right colon (RC) in colonoscopy was suggested to improve adenoma detection rate (ADR), but multicenter data to inform its routine use remain limited. We performed an international multicenter randomized trial comparing SFV versus standard single forward view examination of RC on adenoma detection. METHODS Asymptomatic individuals undergoing screening or surveillance colonoscopies from 6 Asia Pacific regions were invited for study. A forward view examination of RC was first performed in all patients, followed by randomization at hepatic flexure to either SFV examination of RC and standard withdrawal examination from hepatic flexure to rectum, or a standard withdrawal colonoscopy (SWC) examination from hepatic flexure to rectum. Primary outcome was RC ADR. RESULTS Between 2016 and 2019, 1011 patients were randomized (SFV group: 502, SWC group: 509). Forty-five endoscopists performed the colonoscopies. The RC ADR was significantly higher in the SFV group than the SWC group (27.1% vs 21.6%, p=0.042). The whole-colon ADR were high in both groups (49.0% vs 45.0%, p=0.201). SFV examination identified 58 additional adenomas in 49 patients (9.8%), leading to a change in surveillance recommendation in 15 patients (3.0%). The median overall withdrawal time was 1.5 minute longer in the SFV group (12.0 vs 10.5 minutes, p<0.001). Older age, male gender, ever smoking, and longer RC withdrawal time were independent predictors of right-sided adenoma detection. CONCLUSION In this multicenter trial, SFV examination significantly increased RC ADR in screening and surveillance colonoscopies. Routine RC SFV examination should be considered. ClinicalTrials.gov ID: NCT03121495.