title: Colloid carcinoma arising in an anorectal fistula in Crohn's disease: a case report.
abstract: Carcinoma arising in a chronic anorectal fistula in Crohn's disease is rare, but the association has been reported in the literature. In most cases, it concerns a colloid carcinoma. Probably chronic irritation at either end of a fistula can trigger the degeneration of scar tissue into cancer. The diagnosis is difficult, due to lack of specificity of symptoms and signs, and is often delayed, resulting in a poor prognosis. A 70-year-old female, diagnosed with Crohn's disease at the age of 45, developed a pararectal colloid carcinoma in an anorectal fistula that had existed for years. She was treated with an abdominoperineal resection and adjuvant chemotherapy (5-fluorouracil and levofolinate) but died. A high index of suspicion and regular surveillance is recommended in chronic anorectal fistulas in Crohn's disease. In case of doubt, repeated biopsies should be performed to rule out malignancy.
authors.affiliation: Department of abdominal and oncological surgery, AZ Klina Brasschaat, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Devroe
authors.forename: L
authors.initials: L
authors.lastname: Coene
authors.forename: L J M
authors.initials: LJ
authors.lastname: Mortelmans
authors.forename: G
authors.initials: G
authors.lastname: Jutten
mesh_terms: D000368:Aged; D001004:Anus Diseases / Q000150:complications*; D002277:Carcinoma / Q000209:etiology*; D003424:Crohn Disease / Q000150:complications*; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D012003:Rectal Fistula / Q000150:complications*; D012004:Rectal Neoplasms / Q000209:etiology*