2158 The Nationwide Cancer Genome Screening Project for Gastrointestinal Cancer in Japan (GI-SCREEN): Simultaneous identification of KRAS, NRAS, BRAF, and PIK3CA mutation in advanced colorectal cancer (aCRC) (GI-SCREEN 2013-01)

Abstract

resection (11.7%). Colon histological sections were stained with fluorescently labeled lectins, and the lectin binding to surface epithelium, which would be observable in colonoscopy, was compared with conventional histopathology for the presence of disease and disease stage. Results: Normal colonic epithelium (NE) occupied 40.1% of the area of all sections, hyperplastic polyps (HP) occupied 10.2%, low-grade (LGD) dysplasia 25.6%, high-grade (HGD) dysplasia 13.9%, and adenocarcinoma (C) 10.2%, as assessed by conventional histopathology based on H&E staining. Lesions were located in the ascending (10.4%), transverse (15.6%), descending (14.3%), sigmoid (42.9%) colon and rectum (7.8%), with the mean lesion size being 16.0±14.2mm (range 2−60mm). The lectin wheat germ agglutinin (WGA), when fluorescently-labeled, was capable of distinguishing epithelial regions containing NE or HP from regions containing LGD, HGD or cancer, with 81% sensitivity and 87% specificity. Conclusions: Automated analysis of fluorescently-labeled WGA binding to the surface epithelium of excised colon sections may be used for improving the assessment of early dysplasia in CRC. The same fluorescent lectin may also be useful as a topical imaging agent for improving detection of early dysplasia using fluorescence colonoscopy, increasing the early diagnosis of CRC and improving patient survival. No conflict of interest.