Observation of microvessels and invasion in early colorectal neoplasms on narrow band imaging: combination with CD34 and matrix metalloproteinase-7 expression.

Abstract

The study aims to clarify the role of narrow band imaging (NBI) in the prediction of invasion depth and the formation of lesion appearance under NBI with immunohistochemical analysis. As a prospective single-center study, Sano's classification of capillary pattern (CP) was applied to differentiate early colorectal neoplasms under NBI observation. Only lesions with CP type III were analyzed, compared with final histologic findings, and further immunohistochemical analysis with CD34 and matrix metalloproteinase-7 (MMP-7) was performed. As for the 203 cases of CP type III lesions, the sensitivity, specificity, and accuracy for CP type IIIA/IIIB were, respectively, 88.4, 93.6, and 92.5% to differentiate high-grade neoplasia or slight submucosal invasive carcinoma from deep submucosal invasive carcinoma. NBI prediction for invasion depth corresponded to immunohistochemical outcomes of CD34 and MMP-7, which might explain the reason why CP type IIIB displays nearly avascular or loose microvascular areas on the lesion surface. NBI is of excellent use in predicting invasion depth for early colorectal neoplasms, and positive expression of MMP-7 is associated with the appearance of CP type IIIB.