Free perforation due to colonic adenocarcinoma in Crohn's disease.

Free perforation of the bowel due to cancer in Crohn's disease is very rare. One case found among 75 cases of Crohn's disease is reported. The perforation occurred in a mucinous adenocarcinoma of the ascending colon in a 54-year-old woman with a 17-year history of Crohn's disease, who had undergone two previous operations of small bowel and colonic resection. A right hemicolectomy was performed; the patient had an uneventful recovery and does not show recurrence of cancer at 31-month follow-up. This is in contrast with a recent review, in which a very poor prognosis was claimed for the perforated colonic cancer in Crohn's disease.