Appendectomy and risk of prostate cancer in the Health Professionals Follow-up Study.

BACKGROUND:Appendectomy is a common surgical procedure to treat appendicitis. Limited studies examined its association on prostate cancer, with one large cohort study suggesting significant increased risk of overall and advanced prostate cancer, especially among younger men. METHODS:A total of 49,104 men in the Health Professionals Follow-up Study were followed from 1986 to 2016. Cox proportional hazards models were applied to evaluate the association between self-reported history of appendectomy and risk of overall and subtype specific prostate cancer, adjusted for multiple risk factors. RESULTS:During 30 years of follow-up, we documented 7,253 overall prostate cancer including 579 advanced and 1,092 lethal events. Compared to men without appendectomy, those who reported at baseline having had appendectomy were not at higher risk of overall (hazard ratio (HR)=1.01, 95% CI = 0.95 to 1.07), advanced (HR=0.99, 95% CI = 0.81 to 1.23) or lethal (HR=1.04, 95% CI = 0.89 to 1.20) prostate cancer. The association remained null when stratified by age. CONCLUSIONS:We found no evidence of an association between appendectomy and risk of overall and clinically important prostate cancer. IMPACT:We showed that appendectomy was not associated with overall or advanced prostate cancer adjusted for multiple risk factors among a large population of men with 30 years of follow-up.