title: Histologic classification of endoscopically removed flat colorectal polyps: a multicentric study.
abstract: A total of 594 flat colorectal polyps, removed at endoscopy, were histologically classified into non-neoplastic (n = 49) and neoplastic (n = 545) polyps. Non-neoplastic polyps were subdivided into metaplastic (n = 45) and hyperplastic (n = 4), whereas neoplastic polyps were subdivided into adenomas (n = 481), intramucosal carcinomas (n = 28) and invasive adenocarcinomas (n = 36). Several adenoma phenotypes were discerned: tubular (n = 375), serrated (n = 59), villous (n = 39), mixed (n = 7) and fenestrated (n = 1). Intramucosal carcinomas were subdivided into tubular (n = 26) and serrated (n = 2), and invasive adenocarcinomas into tubular (n = 32), serrated (n = 3) and fenestrated (n = 1). The microscopic characteristics of each histologic phenotype described in this communication are defined and illustrated.
authors.affiliation: Department of Pathology, Gastrointestinal Pathology Research Laboratory, Karolinska Institute, Stockholm, Sweden.
authors.forename: C A
authors.initials: CA
authors.lastname: Rubio
authors.forename: Y
authors.initials: Y
authors.lastname: Kato
authors.forename: T
authors.initials: T
authors.lastname: Hirota
authors.forename: T
authors.initials: T
authors.lastname: Muto
mesh_terms: D000236:Adenoma / Q000473:pathology; D003111:Colonic Polyps / Q000145:classification* / Q000473:pathology*; D016099:Endoscopy, Gastrointestinal; D006801:Humans; D011127:Polyps / Q000145:classification* / Q000473:pathology*; D012004:Rectal Neoplasms / Q000473:pathology*