[British and American screening guidelines inadequate for prevention of colorectal carcinoma in patients with inflammatory bowel disease]

Abstract

Objective: To determine how many cases of inflammatory bowel disease (IBD)-related colorectal cancer (CRC) occur before recommended colonoscopy screening commences.

Design: Descriptive.

Method: A nationwide automated histological and cytopathological archive (PALGA) was used to identify patients with IBD and CRC in the period January 1990-June 2006 at the University Medical Center Utrecht, The Netherlands. The interval between the diagnosis of IBD or IBD-related symptoms and the diagnosis of CRC was calculated. The observed interval was compared with the recommended starting point for surveillance according to the British Society of Gastroenterology (BSG) and the American Gastroenterological Association (AGA), i.e. after 8-10 years for pancolitis or after 15-20 years for left-sided colitis.

Results: 33 colorectal cancers were found in 29 patients with IBD. The median age at the time of diagnosis was 29 years (range: 11-82) for IBD and 47 years (range: 23-82) for CRC. 7 of the 29 patients (24%) developed CRC before the minimum recommended time to initiate screening (8 years for pancolitis, 15 years for left-sided colitis), and 9 patients (31%) developed CRC within the maximum recommended time to initiate screening (10 years for pancolitis, 20 years for left-sided colitis). If the onset of IBD-related symptoms was considered the starting point of the disease (rather than the diagnosis of IBD), 17-24% of patients developed a CRC before surveillance would have commenced.

Conclusion: These results suggest that, by following the British and American guidelines for screening for IBD-related CRC, a substantial portion of cases (17-31%) would not be diagnosed in a timely manner.