Interval Colorectal Cancer in Inflammatory Bowel Disease: The Role of Guideline Adherence.

BACKGROUND: Factors associated with interval colorectal cancer (CRC) development in the inflammatory bowel disease (IBD) population remain unclear. AIMS: Among a cohort of patients with interval CRC, we aimed to evaluate IBD characteristics, colonoscopy quality indicators, and surveillance guideline adherence.
METHODS: We performed a retrospective review of IBD- and non-IBD-associated interval CRCs diagnosed between January 2007 and December 2014 within a large US healthcare system. We evaluated risk factors for CRC among patients with IBD. We assessed adherence to surveillance guidelines according to the American Society for Gastrointestinal Endoscopy (IBD surveillance) and the US Multi-Society Task Force on Colorectal Cancer (polyp surveillance). We compared colonoscopy quality measures between patients with and without IBD.
RESULTS: Among 5345 cases of colonic adenocarcinoma, we detected 15 IBD-associated cases of interval CRC and 230 non-IBD-associated cases of interval CRC. Compared to patients without IBD, IBD patients were younger (54.5 vs. 70.4 years; p < 0.0001) and experienced a shorter interval between index colonoscopy and CRC diagnosis (20.7 vs. 35.1 months; p = 0.0009). Fifty three percent (8/15) of interval CRCs in IBD patients were detected within surveillance guidelines. All IBD patients with interval CRC detected after guideline surveillance interval had high-risk features, including active inflammation, previous low-grade or indefinite dysplasia, multiple pseudopolyps on index colonoscopy, or a first-degree relative with CRC. There were no differences in colonoscopy quality measures between patients with and without IBD.
CONCLUSIONS: This study stresses the importance of strict short-interval surveillance for IBD patients with high-risk features, including active inflammation on index colonoscopy.