Narrow band imaging with magnifying colonoscopy as diagnostic tool for predicting histology of early colorectal neoplasia

Background The presence of abnormal microcapillaries detected by narrow band imaging (NBI) with magnifying colonoscopy has been reported to be a marker of colorectal neoplasia. Aim To investigate prospectively if NBI with magnification could help predict the histology of early colorectal neoplasia. Methods A series of 104 consecutive patients with 139 colorectal lesions were studied. All lesions were detected by conventional colonoscopy and subsequently evaluated by NBI with magnification. During NBI with magnification, the microvascular architecture observed on the surface of the detected lesions, capillary patterns (CP), was divided into non-neoplastic (CP I) and neoplastic (CP II and CP III) types. Only lesions endoscopically diagnosed as CP II or CP III were included in the study. All of the lesions were resected endoscopically or surgically and examined histologically for comparison. Results Ninety-seven per cent (n = 103) of colorectal neoplastic lesions with CP II were histologically diagnosed as low-grade dysplasia. Eighty-seven per cent (n = 31) of the colorectal neoplastic lesions with CP III were high-grade dysplasia or invasive cancer. Conclusion Capillary patterns observed by NBI with magnification could be used to assess the degree of atypia in early colorectal neoplasia.