A "RESECT AND DISCARD" STRATEGY USING MAGNIFYING NARROW-BAND IMAGING: A PHASE II PROSPECTIVE STUDY

INTRODUCTION: Elimination of histopathological diagnosis for removed small colorectal polyps using non-magnifying narrow-band imaging (N-NBI), that is "resect & discard" strategy, was proposed for cost reduction on colorectal cancer screening without taking into consideration the advanced histology.AIMS: To investigate the efficacy and safety of the new "resect & discard" strategy taking into consideration advanced histology using magnifying-NBI (M-NBI) in a prospective phase II trial at a tertiary center. METHODS: All polyp histology was optically diagnosed using N-NBI followed by M-NBI and decisions made as to polyp management and surveillance interval. After all polyps were biopsied or resected, optical and histopathological diagnosis results were compared. RESULTS: 1152 lesions smaller than 10mm in 464 patients were assessed histopathology. The management of 81% of the small polyps could be decided without formal histopathology using M-NBI. The sensitivity, specificity and accuracy (95% confidence interval) of M-NBI in distinguishing lesions with advanced histology from low-grade adenoma and non-neoplastic lesions were0.77 (0.60-0.88), 0.93 (0.92-0.93) and 0.92 (0.91-0.93), respectively. Agreements in determining surveillance interval (BSG, US) using M-NBI (90%, 89%) were higher than that using N-NBI (85%, 84%). COUCLUSION: M-NBI could differentiate most of the lesions with advanced histology and had a better diagnostic performance compared to N-NBI. M-NBI can be a promising tool for the new "resect & discard" strategy.