Implications of Prostate Cancer Treatment in Men With Inflammatory Bowel Disease.

OBJECTIVE: To investigate the influences of inflammatory bowel disease (IBD), a rare but morbid disease with increasing incidence, on prostate cancer management decisions. We examined whether prostate cancer treatment differed for men with IBD, and whether treatment choice was associated with risk of IBD flare.

MATERIALS AND METHODS: Using Veterans Health Administration cancer registry and administrative data, we identified 52,311 men diagnosed with prostate cancer from 2005 to 2008. We used International Classification of Diseases-9 codes and pharmacy and utilization data to identify IBD diagnoses, IBD-directed therapy, and flares (glucocorticoid escalation, hospitalization, and surgical intervention). We compared characteristics across men with and without IBD, and used multivariable regression to examine IBD flares after treatment according to treatment type.

RESULTS: Two hundred and forty men (0.5%) had IBD prior to prostate cancer diagnosis. Compared to non-IBD patients, IBD patients were more likely Caucasian (P < .001) with lower-risk cancer (P = .02). Surgery was more common in IBD patients (41% vs 28%, P < .001). In the year following prostate cancer treatment, 18% of IBD patients experienced flares. After adjustment, the only predictor of flare in the year after treatment was flare in the year prior to treatment (adjusted odds ratio, 12.5; 95% confidence interval, 5.4-29.2).

CONCLUSION: IBD patients were more likely to have lower-risk disease and be treated with surgery. Choice of prostate cancer treatment did not predict flares in the subsequent year. Better understanding of the intersection of IBD and prostate cancer can help inform treatment decisions for the increasing number of men managing both diseases.