Cancer in inflammatory bowel disease 15 years after diagnosis in a population-based European Collaborative follow-up study

AIM OF THE STUDY: To determine the occurrence of intestinal and extraintestinal cancers in the 1993-2009 prospective European Collaborative Inflammatory Bowel Disease (EC-IBD) Study Group cohort. PATIENTS-METHODS: A physician per patient form was completed for 681 inflammatory bowel disease patients (445UC/236CD) from 9 centers (7 countries) derived from the original EC-IBD cohort. For the 15-year follow up period, rates of detection of intestinal and extraintestinal cancers were computed. RESULTS: Patient follow-up time was fifteen years. In total 62/681 patients (9.1%) [41 with ulcerative colitis/21 with Crohn's disease, 36 males/26 females] were diagnosed with sixty-six cancers (four patients with double cancers). Colorectal cancer was diagnosed in 9/681 patients [1.3%] (1 Crohn's disease and 8 ulcerative colitis). The remaining 53 cancers were extraintestinal. There was a higher prevalence of intestinal cancer in the Northern centers compared to Southern centers [p=NS]. Southern centers had more cases of extraintestinal cancer compared to Northern centers [p=NS]. The frequency of all observed types of cancers in Northern and in Southern centers did not differ compared to the expected one in the background population. CONCLUSIONS: In the fifteen-year follow up of the EC-IBD Study Group cohort the prevalence of cancer was 9.1% with most patients having a single neoplasm and an extraintestinal neoplasm. In Northern centers there were more intestinal cancers while in Southern centers there were more extraintestinal cancers compared to Northern centers. In this IBD cohort the frequency of observed cancers was not different from that expected in the background population.