Diagnostic Ability Of Japan Narrow-Band Imaging Expert Team Classification For Colorectal Lesions By Magnifying Endoscopy With Blue Laser Imaging Versus Narrow-Band Imaging

Background and study aims The Japan Narrow-band imaging (NBI) Expert Team (JNET) classification was proposed for evaluating colorectal lesions. However, it remains unknown whether the JNET classification can be applied to magnifying endoscopy with image-enhanced endoscopies other than NBI. This study aimed to compare the diagnostic ability of JNET classification by magnifying endoscopy with blue laser imaging (ME-BLI) and with ME-NBI.Patients and methods We retrospectively assessed consecutive patients diagnosed per the JNET classification by ME-BLI (BLI group) or ME-NBI (NBI group) between March 2014 and June 2017. We compared the diagnostic value of JNET classification between the groups with one-to-one propensity score matching.Results Four hundred and seventy-one propensity score-matched pairs of lesions were analyzed. In the BLI and NBI groups, the overall diagnostic accuracies were 92.1% and 91.7%, respectively, and those for differentiating between neoplastic and non-neoplastic polyps were 96.6% and 96.8%, respectively. The positive predictive value by each JNET classification in BLI vs. NBI group was 90.6% vs. 96.2% in Type 1, 94.3% vs. 94.6% in Type 2A, 57.7% vs. 42.3% in Type 2B, and 100% vs. 91.7% in Type 3.The negative predictive value was 97.0% vs. 96.9% in Type 1, 88.1% vs. 82.8% in Type 2A, 98.0% vs. 98.2% in Type 2B, and 98.5% vs. 98.7% in Type 3. No statistical difference in the diagnostic results was found between the groups.Conclusions The diagnostic ability of the JNET classification by ME-BLI and ME-NBI was comparable, with the former also applicable for diagnosis of colorectal lesions.