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colorectal villous adenoma
Friday 31 March 2006
Colorectal Villous Adenomas
Approximately 20% of a symptomatic persons screened by colonoscopy have villous adenomas, a third of which contain high-grade dysplasia.
Slightly < 2% contain invasive carcinoma.
Villous adenomas consist of elongated ﬁnger-like non-branching fronds of dysplastic epithelium extending outward from the muscularis mucosae to the colonic lumen.
The villi contain cores oflamina propria covered by a single layer of adenomatous epithelium
It has been deﬁned that villous lesions as those that contain
> 80% of a villous component.
- colorectal tubular adenoma