Endoscopic resection of asymptomatic, colonic, polypoid arteriovenous malformations: Two case reports and a literature review.

A colonic arteriovenous malformation (AVM) is a significant vascular lesion of the gastrointestinal tract and a common cause of lower gastrointestinal bleeding. AVMs are usually identified endoscopically as bright red, flat lesions. AVMs with a polypoid appearance are extremely rare in the large intestine.