Purpose: Data supporting an increased risk of colorectal cancer in patients with Crohn's colitis are inconsistent. Despite this, clinical recommendations regarding colonoscopic screening and surveillance for patients with Crohn's colitis are extrapolated from chronic ulcerative colitis protocols. The primary aim of our study was to determine the incidence of dysplasia and carcinoma in pathology specimens of patients undergoing segmental or total colectomy for Crohn's disease of the large bowel. In addition, we sought to identify risk factors associated with the development of dysplasia and carcinoma.
Methods: We performed a retrospective review of all patients operated on at our institution for Crohn's colitis between January 1992 and May 2004. Data were retrieved from patient charts, operative notes, and pathology reports. Logistic regression was used to model the probability of having dysplasia or adenocarcinoma.
Results: Two hundred twenty-two patients (138 females) who underwent surgical resection for the treatment of Crohn's colitis were included in the study. Mean age at surgery was 41 (range, 15-82) years and the mean duration of disease was 10 (range, 0-53) years. There were five cases of dysplasia (2.3 percent) and six cases of adenocarcinoma (2.7 percent). Three patients with dysplasia and one with adenocarcinoma were diagnosed on preoperative colonoscopy; while the other cases were discovered incidentally on pathologic examination of resected specimens. Factors associated with the presence of dysplasia or adenocarcinoma included older age at diagnosis (38.2 vs. 30.3 years, P = 0.02), longer disease duration (16.0 vs. 10.1 years, P = 0.05), and disease extent (90 percent extensive vs. 59 percent limited, P = 0.05).
Conclusions: Patients with severe Crohn's colitis requiring surgery are at significant risk for developing dysplasia and adenocarcinoma, particularly when diagnosed at an older age, after longer disease duration, and with more extensive colon involvement.