Impact of the diagnosis and treatment of cancer on the course of inflammatory bowel disease.

BACKGROUND The effects of extra-intestinal cancer on the course of inflammatory bowel disease (IBD) are poorly understood. AIM To evaluate the impact of cancer and its management on IBD outcomes. METHODS A total 80 IBD patients (51 Crohn's disease, 29 ulcerative colitis; 33 men, median age at cancer diagnosis 48yrs) diagnosed with extra-intestinal cancer were selected from a prospective database. IBD activity and therapeutic requirements (assessed year-by-year) were compared before and after cancer diagnosis, with a control group of patients without cancer matched for gender, birth date, date of IBD diagnosis and IBD phenotype. RESULTS Paired comparisons of the consecutive periods before and after cancer diagnosis did not show significant changes in median (IQR) percentages of years with active disease (27% [0-50] vs. 19% [0-53]), while the proportion of patient-years on any immunosuppressant remained stable (26% vs. 28%). Chemotherapy had no significant effect on IBD activity. Compared to controls, patients with cancer had a similar IBD activity and use of anti-TNF, but less use of immunomodulators (19% vs. 25%, p<0,001) and an increased rate of surgery (4% vs. 2.5%, p<0,05). Individual variations in IBD activity after cancer diagnosis were not significantly different in patients with cancer and their matched controls. CONCLUSION Occurrence of extra-intestinal cancer impacts IBD therapeutic management, with a trend towards less use of immunomodulators and more surgery. In the long-term, cancer diagnoses and treatments do not modify IBD outcomes.