Effects of cancer treatment on inflammatory bowel disease remission and reactivation

Background & aims: Little is known about the effects of cancer therapy for extraintestinal malignancy in patients with inflammatory bowel diseases (IBDs).

Methods: We analyzed data from the Massachusetts General Hospital and the Brigham and Women's Hospital on 84 patients diagnosed with Crohn's disease, ulcerative colitis, or indeterminate colitis found to have a solid malignant extraintestinal neoplasm between January 15, 1993, and December 15, 2011. We investigated the incidence of remission with cancer treatment (cytotoxic chemotherapy, hormone therapy, or both) among patients with active IBD (n = 15) and time to disease activation after cancer treatment of those with inactive disease (n = 69). Cox proportional hazards models and survival curves were constructed to identify independent predictors of these outcomes.

Results: Among patients with active IBD at cancer diagnosis, 66.7% (n = 10/15) achieved remission during cancer treatment; the median duration of remission was 27 months. Ninety percent of these patients had received cytotoxic chemotherapy. For patients with IBD in remission at cancer diagnosis, 17.4% (n = 12/69) developed active IBD; the type of treatment was the strongest predictor of IBD reactivation. The risk of IBD reactivation was greatest among patients who received a combination of cytotoxic chemotherapy and adjuvant hormone therapy (hazard ratio, 12.25; 95% confidence interval, 1.51-99.06) or only hormone therapy (hazard ratio, 11.56; 95% confidence interval, 1.39-96.43). Ninety percent of patients who received cytotoxic chemotherapy remained in remission at 5 years compared with 64% of those who received only hormone therapy or the combination of cytotoxic chemotherapy and adjuvant hormone therapy (log rank, P = .02).

Conclusions: IBD is more likely to remit among patients who receive cytotoxic chemotherapy for solid malignancies than those who receive only hormone therapy or the combination of cytotoxic chemotherapy and adjuvant hormone therapy. Among patients with inactive IBD at the time of cancer diagnosis, hormonal therapy, alone or in combination with cytotoxic chemotherapy, increases the risk of IBD reactivation.