Intestinal cancer in patients with Crohn's disease

Surveillance of intestinal cancer in Crohn's disease (CD) has often been advocated. To date, no clear evidence exists whether CD patients are at special risk for intestinal cancer. An increased incidence of small bowel adenocarcinoma is suggested. However, recent figures also suggest an increased risk of CD associated colorectal cancer. We report our experience with 10 cases of CD complicated by intestinal adenocarcinoma.

Our institutional database included 330 patients treated for CD between 1988-2005. Data of patients that developed carcinoma within Crohn's lesions of either small or large bowel were analyzed.

Ten patients were diagnosed with CD complicated by carcinoma. In nine patients, cancer was present in the colorectum and in one, in Crohn's ileitis. Tumors were in conjunction with fistulae in three and developed within strictures in five patients. Mean age at the time of diagnosis of CD was 43 years. Mean duration of CD until diagnosis of cancer was 14 years. Only five patients were diagnosed for cancer preoperatively. Staging revealed advanced tumors in almost all patients. Mean survival after surgery was 29 months (2-149 months).

Cancer risk in CD and especially in Crohn's colitis may still be underestimated. Delayed diagnosis resulted in a poor prognosis. The value of colonoscopy as surveillance tool is questioned by the fact that in our patients, carcinoma was diagnosed in some patients preoperatively by routine colonoscopy. Therefore, additional markers should be identified to detect CD patients at risk.