Table 2: NICE classification.

Type 1 Type 2 Type 3 Color Same or lighter than background Browner relative to background (verify color arises from vessels) Brown to dark brown relative to background; sometimes patchy whiter areas Vessels None, or isolated lacy vessels may be present coursing across the lesion Brown vessels surrounding white structures** Has area(s) of disrupted or missing vessels Surface pattern Dark or white spots of uniform size, or homogeneous absence of pattern Oval, tubular or branched white structures** surrounded by brown vessels Amorphous or absent surface pattern Most likely pathology Hyperplastic Adenoma*** Deep submucosalinvasive cancer Treatment Followup Polypectomy/EMR/ESD Surgery

*Can be applied using colonoscopes with/without optical (zoom) magnification. **These structures (regular or irregular) may represent the pits and the epithelium of the crypt opening. ***Type 2 consists of Vienna classification types 3, 4 and superficial 5 (all adenomas with either low or high grade dysplasia, or with superficial submucosal carcinoma). The presence of high grade dysplasia or superficial submucosal carcinoma may be suggested by an irregular vessel or surface pattern, and is often associated with atypical morphology (e.g., depressed area).