Inflammatory Bowel Disease and the Risk of Prostate Cancer

Background: There are limited data examining the risk of prostate cancer (PCa) in patients with inflammatory bowel disease (IBD).

Objective: To compare the incidence of PCa between men with and those without IBD.

Design, setting, and participants: This was a retrospective, matched-cohort study involving a single academic medical center and conducted from 1996 to 2017. Male patients with IBD (cases=1033) were randomly matched 1:9 by age and race to men without IBD (controls=9306). All patients had undergone at least one prostate-specific antigen (PSA) screening test.

Outcome measurements and statistical analysis: Kaplan-Meier and multivariable Cox proportional hazard models, stratified by age and race, evaluated the relationship between IBD and the incidence of any PCa and clinically significant PCa (Gleason grade group ≥2). A mixed-effect regression model assessed the association of IBD with PSA level.

Results and limitations: PCa incidence at 10yr was 4.4% among men with IBD and 0.65% among controls (hazard ratio [HR] 4.84 [3.34-7.02] [3.19-6.69], p<0.001). Clinically significant PCa incidence at 10yr was 2.4% for men with IBD and 0.42% for controls (HR 4.04 [2.52-6.48], p<0.001). After approximately age 60, PSA values were higher among patients with IBD (fixed-effect interaction of age and patient group: p=0.004). Results are limited by the retrospective nature of the analysis and lack of external validity.

Conclusions: Men with IBD had higher rates of clinically significant PCa when compared with age- and race-matched controls.

Patient summary: This study of over 10000 men treated at a large medical center suggests that men with inflammatory bowel disease may be at a higher risk of prostate cancer than the general population.