title: Flat adenoma and flat mucosal carcinoma (IIb type)--a new precursor of colorectal carcinoma? Report of two cases.
abstract: Two flat adenomas and a flat mucosal carcinoma of the colon were reported in patients with synchronous and metachronous colonic carcinomas. These lesions were almost flat and were not detected by preoperative endoscopic examinations. Colonoscopists should be aware of the presence of flat adenomas, which can be easily missed, and recognize them as lesions that play an important role in the "adenoma-carcinoma sequence."
authors.affiliation: First Department of Surgery, University of Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Adachi
authors.forename: T
authors.initials: T
authors.lastname: Muto
authors.forename: Y
authors.initials: Y
authors.lastname: Morioka
authors.forename: T
authors.initials: T
authors.lastname: Ikenaga
authors.forename: M
authors.initials: M
authors.lastname: Hara
mesh_terms: D000236:Adenoma / Q000473:pathology*; D002277:Carcinoma / Q000209:etiology / Q000473:pathology*; D003106:Colon / Q000473:pathology*; D003110:Colonic Neoplasms / Q000209:etiology / Q000473:pathology*; D003113:Colonoscopy; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012004:Rectal Neoplasms / Q000209:etiology