title: Endoscopic resection of asymptomatic, colonic, polypoid arteriovenous malformations: Two case reports and a literature review.
abstract: 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. We present two cases of colonic polypoid AVM, which were detected incidentally during screening colonoscopy. Both the patients had no history of gastrointestinal bleeding such as melena or hematochezia. Colonoscopy revealed pedunculated polyps overlaid by hyperemic mucosa in the ascending colon and proximal sigmoid colon. Microscopic examination showed aberrant vessels with thickened, hypertrophic walls in the mucosa and the submucosa, and arteries were directly connected to veins without capillary beds. These features were compatible with a diagnosis of AVM with a polypoid appearance. No immediate or delayed bleeding was noted after polypectomy.
authors.affiliation: Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Han-Hee
authors.initials: HH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Hyuk-Min
authors.initials: HM
authors.lastname: Kwon
authors.affiliation: Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Sanghyun
authors.initials: S
authors.lastname: Gil
authors.affiliation: Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Young-Shin
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Minjung
authors.initials: M
authors.lastname: Cho
authors.affiliation: Department of Hospital Pathology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Seo
authors.affiliation: Department of Internal Medicine, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea.
authors.forename: Hiun-Suk
authors.initials: HS
authors.lastname: Chae
authors.affiliation: Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Cho
mesh_terms: D000368:Aged; D001165:Arteriovenous Malformations / Q000175:diagnosis / Q000601:surgery*; D003111:Colonic Polyps / Q000175:diagnosis / Q000601:surgery*; D003113:Colonoscopy / Q000379:methods; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome