P431 Clinical epidemiology and phenotypic characteristics of Crohn's disease in Saudi Arabia

Abstract

disease (IBD)-associated colorectal cancer (CRC) in populationbased cohorts. Methods: Among the 19,451 new cases of CRC recorded in the Burgundy digestive cancer registry between 1976 and 2008, all cases of IBD-associated CRC were identified. Incidence rates were age-standardised according to the world standard population. Prognosis was determined using univariate and multivariate relative survival. Results: Thirty-eight IBD-associated CRC were identified (ulcerative colitis, n = 29 and Crohn’s disease, n = 9). The mean age at CRC diagnosis was greater for patients without IBD than those with IBD (70.9 versus 56.9 years, respectively; p < 0.001). Distributions of gender, stage at presentation, location, and histological type of CRC did not differ from those of sporadic cases. The overall world age-standardised incidence of IBD-associated CRC per 100,000 was 0.11 (SD: 0.03) for men and 0.06 (SD: 0.02) for women. Only age was independently associated with IBD-associated CRC (OR: 0.22; 95% CI: 0.12 0.43; p < 0.001). Treatment modalities did not differ between IBD and non-IBD patients. Five-year relative survival was 51.9% (95% CI: 51.1 52.8%) in non-IBD patients and 41.3% (95% CI: 24.6 57.2%) in IBD patients (p = 0.201). After adjustment for age, gender and stage at diagnosis, the excess hazard of death was 1.46 times higher in IBD than in non-IBD patients (95% CI: 0.94 2.27; p = 0.070). Conclusions: Apart from age, the characteristics of IBDassociated CRC were similar to those of non-IBD CRC. The prognosis of CRC may be poorer in patients with IBD than in those without IBD.