Few studies discussed the link between benign prostatic hyperplasia (BPH) and bladder cancer. We performed this cohort study to investigate whether there is an association between BPH and subsequent risk of bladder cancer.
We identified 35,092 study subjects including 17546 BPH patients and 17546 comparisons from the National Health Insurance database. The comparison cohort was frequency matched with age and index-year. We measured subsequent bladder cancer rates (per 1000 person-years) in two cohorts. Attributable risks (ARs) was calculated based on the bladder cancer rates in two cohorts. The hazard ratios (HRs) and 95% confidence intervals (CIs) for bladder cancer were estimated via Cox proportional hazard regression.
BPH patients had a higher bladder cancer rate than comparisons (AR = 0.81 per 1000 person-years) and exhibited 4.69- and 4.11-fold increases in bladder cancer risk in the crude and adjusted Cox models, respectively (95% CIs = 4.15-6.99 and 2.70-6.26). The AR was highest in patients aged 65-74 years old (AR = 1.33). BPH patients with chronic kidney disease were at an elevated bladder cancer risk. Regarding the association between bladder cancer and transurethral prostatectomy (TURP), BPH patients who underwent TURP were at a higher risk of bladder cancer (AR = 1.69; HR = 6.17, 95% CI = 3.68-10.3) than those who did not (AR = 0.69; HR = 3.73, 95% CI = 2.43-5.74).
In this study, BPH patients were found to have an increased risk of subsequent bladder cancer. Based on the limitations of retrospective nature, further studies are needed.
World journal of urology. 2018 Feb 09 [Epub ahead of print]
Chu-Wen Fang, Cheng-Hsi Liao, Shih-Chi Wu, Chih-Hsin Muo
Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan., Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan., Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan. ., Management Office for Health Data, China Medical University and Hospital, No. 2, Yuh-Der Road, Taichung, 404, Taiwan.