Efficiency of Colorectal Cancer Surveillance in Patients with Ulcerative Colitis: 38 Years' Experience in a Patient Cohort from a Defined Population Area.

BACKGROUND AND AIMS: Ulcerative colitis increases the risk of developing colorectal cancer. Colonoscopic surveillance is recommended although there are no randomized trials evaluating the efficacy of such a strategy. This study is an update of earlier studies from an ongoing colonoscopic surveillance program.

MATERIAL AND METHODS: All patients with ulcerative colitis were invited to the surveillance program that started in 1977 at Örnsköldsvik Hospital, located in the northern part of Sweden. Five principal endoscopists performed the colonoscopies and harvested mucosal sampling for histopathological evaluation. Some 323 patients from the defined catchment area were studied from 1977 to 2014. At the end of the study period, 130 patients, including those operated on, had had total colitis for more than 10 years.

RESULTS: In total, 1481 colonoscopies were performed on 323 patients during the study period without any major complications. In all, 10 cases of colorectal cancer were diagnosed in 9 patients, of whom 1 died from colorectal cancer. The cumulative incidence of colorectal cancer was 1.4% at 10 years, 2.0% at 20 years, 3.0% at 30 years, and 9.4% at 40 years of disease duration, respectively. The standardized colorectal cancer incidence ratio was 3.01 (95% confidence interval: 1.42-5.91). Major surgery was performed on 65 patients; for 20 of these, the indication for surgery was dysplasia or colorectal cancer. Panproctocolectomy was performed in 43 patients.

CONCLUSION: This study supports that colonoscopic surveillance is a safe and effective long-term measure to detect dysplasia and progression to cancer. The low numbers of colorectal cancer-related deaths in our study suggest that early detection of neoplasia and adequate surgical intervention within a surveillance program may reduce colorectal cancer mortality in ulcerative colitis patients.