[Carcinoma arising from ileorectal fistula in a patient with Crohn's disease].

A 72-year-old man was given a diagnosis of Crohn's disease in 1976 at age 44, and partial resection of is ileum was performed. In November 1982, barium enema examination revealed on ileorectal fistula. As he had no complaint, conservative therapy was chosen. In August 2003, he had high fever and CT scan revealed presacral abscess. Ileocecal resection, partial resection of is small intestine and loop sigmoid colostomy were performed. In December 2004, the serum level of CEA was gradually elevated and he complained of anal mucus discharge. Endoscopic examination showed a fistula orifice in the rectum and biopsy of the fistula revealed mucinous adenocarcinoma. We performed abdominoperineal resection of the rectum with partial resection of the sacrum. We thought that careful observation helped the detection of such a rare case of carcinoma arising from a fistula tract.