Background: 5α-reductase inhibitors (5-ARIs) inhibit the pathway of converting the testosterone to dihydrotestosterone and are widely used in benign prostatic hyperplasia patients. Since androgen receptor activation may play a role in urothelial tumorigenesis, we conducted this retrospective cohort study to determine whether 5α-reductase inhibitors (5-ARIs) administration is associated with bladder cancer mortality, bladder cancer recurrence and upper tract urothelial carcinoma mortality, using the Taiwan National Health Insurance database.
Methods: The data of this retrospective cohort study were sourced from the Longitudinal Health Insurance Database of Taiwan, compiled by the Taiwan National Health Insurance database from 1996 to 2010. It consists of 18,530 men with bladder cancer, of whom 474 were 5-ARIs recipients and 4384 men with upper tract urothelial carcinoma, of whom 109 were 5-ARIs recipients. Propensity Score Matching on the age and geographic data was done at the ratio of 1:10. We analyzed the odds ratios (OR) and 95% confidence interval (CI) of the risk of bladder cancer death, bladder cancer recurrence rate and upper tract urothelial carcinoma related death by the 5-ARIs administration.
Results: Those who received 5-ARIs showed a lower risk of bladder cancer related death compared to nonusers in multivariable adjusted analysis (OR 0.835, 95% CI 0.71-0.98). However, there was no significant difference in the bladder cancer recurrence rate (OR 0.956, 95% CI 0.82-1.11) and upper tract urothelial carcinoma related mortality in multivariable adjusted analysis (OR 0.814, 95% CI 0.6-1.1).
Conclusions: Patients who receive 5-ARIs have lower bladder cancer related mortality compared to those who don't. 5-ARIs may prove to be a viable strategy to improve bladder cancer outcomes.
Keywords: 5α-reductase inhibitors (5-ARIs); Androgen receptor (AR); Bladder cancer; Dutasteride; Finasteride; Upper tract urothelial carcinoma.