Comparison of adenoma miss rate and adenoma detection rate between conventional colonoscopy and colonoscopy with second-generation distal attachment cuff: a multicenter, randomized, back-to-back trial

Background and Aims Endocuff Vision (Olympus Europe, Hamburg, Germany) has been designed to enhance mucosal visualization, thereby improving detection of (pre-)malignant colorectal lesions. This multicenter, international, back-to-back, randomized colonoscopy trial compared the adenoma detection rate (ADR) and adenoma miss rate (AMR) between Endocuff Vision–assisted colonoscopy (EVC) and conventional colonoscopy (CC). Methods Patients aged 40 to 75 years referred for non–immunochemical fecal occult blood test–based screening, surveillance, or diagnostic colonoscopy were included at 10 hospitals and randomized into 4 groups: group 1, 2 × CC; group 2, CC followed by EVC; group 3, EVC followed by CC; and group 4, 2 × EVC. Primary outcomes included ADR and AMR. Results A total of 717 patients were randomized, of whom 661 patients (92.2%) had 1 and 646 (90.1%) patients had 2 completed back-to-back colonoscopies. EVC did not significantly improve ADR compared to CC (41.1%; [95% confidence interval (CI), 36.1-46.3] vs 35.5% [95% CI, 30.7-40.6], respectively; P = .125), but EVC did reduce AMR by 11.7% (29.6% [95% CI, 23.6-36.5] vs 17.9% [95% CI, 12.5-23.5], respectively; P = .049). AMR of 2 × CC compared to 2 × EVC was also not significantly different (25.9% [95% CI, 19.3-33.9] vs 18.8% [95% CI, 13.9-24.8], respectively; P = .172). Only 3.7% of the polyps missed during the first procedures had advanced pathologic features. Factors affecting risk of missing adenomas were age (P = .002), Boston Bowel Preparation Scale (P = .008), and region where colonoscopy was performed (P < .001). Conclusions Our trial shows that EVC reduces the risk of missing adenomas but does not lead to a significantly improved ADR. Remarkably, 25% of adenomas are still missed during conventional colonoscopies, which is not different from miss rates reported 25 years ago; reassuringly, advanced features were only found in 3.7% of these missed lesions. (Clinical trial registration number: NCT03418948.) Endocuff Vision (Olympus Europe, Hamburg, Germany) has been designed to enhance mucosal visualization, thereby improving detection of (pre-)malignant colorectal lesions. This multicenter, international, back-to-back, randomized colonoscopy trial compared the adenoma detection rate (ADR) and adenoma miss rate (AMR) between Endocuff Vision–assisted colonoscopy (EVC) and conventional colonoscopy (CC). Patients aged 40 to 75 years referred for non–immunochemical fecal occult blood test–based screening, surveillance, or diagnostic colonoscopy were included at 10 hospitals and randomized into 4 groups: group 1, 2 × CC; group 2, CC followed by EVC; group 3, EVC followed by CC; and group 4, 2 × EVC. Primary outcomes included ADR and AMR. A total of 717 patients were randomized, of whom 661 patients (92.2%) had 1 and 646 (90.1%) patients had 2 completed back-to-back colonoscopies. EVC did not significantly improve ADR compared to CC (41.1%; [95% confidence interval (CI), 36.1-46.3] vs 35.5% [95% CI, 30.7-40.6], respectively; P = .125), but EVC did reduce AMR by 11.7% (29.6% [95% CI, 23.6-36.5] vs 17.9% [95% CI, 12.5-23.5], respectively; P = .049). AMR of 2 × CC compared to 2 × EVC was also not significantly different (25.9% [95% CI, 19.3-33.9] vs 18.8% [95% CI, 13.9-24.8], respectively; P = .172). Only 3.7% of the polyps missed during the first procedures had advanced pathologic features. Factors affecting risk of missing adenomas were age (P = .002), Boston Bowel Preparation Scale (P = .008), and region where colonoscopy was performed (P < .001). Our trial shows that EVC reduces the risk of missing adenomas but does not lead to a significantly improved ADR. Remarkably, 25% of adenomas are still missed during conventional colonoscopies, which is not different from miss rates reported 25 years ago; reassuringly, advanced features were only found in 3.7% of these missed lesions. (Clinical trial registration number: NCT03418948.)