title: Development of an aggressive depressed cancer in a case of familial adenomatous polyposis.
abstract: In 1977, Kariya et al. reported a case of a small depressed cancer in a patient with familial adenomatous polyposis (FAP) raising the possibility that not all cancers in FAP develop from polypoid adenomas. It is now becoming widely recognized that colonic adenomas may appear as flat or depressed lesions. However, colorectal cancers developing in patients with familial adenomatous polyposis (FAP) are still thought to evolve from adenomatous polyps following the polyp-carcinoma sequence. We report the case of a patient with FAP in whom rectal carcinoma developed 23 years after subtotal colectomy and ileorectal anastomosis. We suggest that this malignancy may have developed de novo because of the depressed shape of the lesion and the aggressive growth pattern. This case raises the possibility that carcinomas may not always evolve from polyps in FAP. Aggressive cancers with a depressed appearance should be searched for when surveying the rectal stump in patients with FAP.
authors.affiliation: Division of Gastrointestinal Endoscopy, National Cancer Center Hospital, Tokyo, Japan. ytsaito@mitsuihosp.or.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Fujii
authors.forename: T
authors.initials: T
authors.lastname: Akasu
authors.forename: T
authors.initials: T
authors.lastname: Gotoda
authors.forename: T
authors.initials: T
authors.lastname: Kozu
authors.forename: D
authors.initials: D
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Sano
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary*; D011125:Adenomatous Polyposis Coli / Q000473:pathology*; D000328:Adult; D003113:Colonoscopy; D006801:Humans; D008297:Male; D012004:Rectal Neoplasms / Q000556:secondary*