Incidence, Management, and Course of Cancer in Patients with Inflammatory Bowel Disease

Background and aims: Patients with inflammatory bowel disease [IBD] are at increased risk for developing some types of neoplasia. Our aims were to determin the risk for cancer in patients with IBD and to describe the relationship with immunosuppressive therapies and clinical management after tumor diagnosis. Methods: Retrospective, multicenter, observational, 5-year follow-up, cohort study. Relative risk [RR] of cancer in the IBD cohort and the background population, therapeutic strategies, and cancer evolution were analyzed. Results: A total of 145 cancers were diagnosed in 133 of 9100 patients with IBD (global cumulative incidence 1.6% vs 2.4% in local population; RR = 0.67; 95% confidence interval [CI]: 0.57-0.78). Patients with IBD had a significantly increased RR of non-melanoma skin cancer [RR = 3.85; 2.53-5.80] and small bowel cancer [RR = 3.70; 1.23-11.13]. After cancer diagnosis, IBD treatment was maintained in 13 of 27 [48.1%] patients on thiopurines, in 2 of 3 on methotrexate [66.6%], none on anti-TNF-alpha monotherapy [n = 6] and 4 of 12 [33.3%] patients on combined therapy. Rate of death and cancer remission during follow-up did not differ [p > 0.05] between patients who maintained the treatment compared with patients who withdrew [5% vs 8% and 95% vs 74%, respectively]. An association between thiopurines [p = 0.20] or anti-TNF-alpha drugs [p = 0.77] and cancer was not found. Conclusions: Patients with IBD have an increased risk for non-melanoma skin cancer and small bowel cancer. Immunosuppresive therapy is not related to a higher overall risk for cancer or worse tumor evolution in patients who maintain these drugs after cancer diagnosis.