Use of 5α-reductase inhibitors (5-ARIs) prior to a bladder cancer diagnosis may reduce patients’ risks for disease progression.
Using the Korean National Health Insurance Service database, investigators identified 22,845 men diagnosed with bladder cancer who had pre-existing benign prostatic hyperplasia (BPH) treated with an α-blocker with or without a 5-ARI. To reduce biases, they propensity-score matched 5300 users of α-blockers only to 5300 users of 5-ARIs plus α-blockers. BPH medications were required to be taken 12 or more months before bladder cancer diagnosis.
The 5-ARI plus α-blocker group had a significant adjusted 16% and 26% lower risk of bladder instillation and radical cystectomy, respectively, compared with the α-blocker only group, indicating delayed grade and stage progression with 5-ARI use, Seok Ho Kang, MD, PhD, of Anam Hospital, Korea University College of Medicine, in Seoul, Korea, and colleagues reported in JAMA Network Open. The 5-ARI group also had a significant 17% reduced risk for all-cause mortality.
The between-group differences in restricted mean survival time were 88.1 days for bladder instillation, 68.0 days for radical cystectomy, and 92.6 days for all-cause mortality.
The investigators also found that the 5-ARI plus α-blocker group had numerically lower incidence rates per 1000 person-years of bladder instillation (66.43 vs 85.59) and radical cystectomy (13.56 vs 19.57), compared with the α-blocker only group.
The investigators found that only 5-ARI use of 2 years or more was significantly associated with reduced risk of radical cystectomy.
Results of previous studies have been conflicting with some showing benefit of 5-ARI treatment and others showing no benefit.
“This cohort study found that the prediagnostic prescription of a 5-ARI was associated with a reduced risk of [bladder cancer] progression,” Dr Kang’s team wrote. “However, the evidence was insufficient to inform the extension of 5-ARI indications. A prospective cohort study or RCT is needed to validate the findings of this study.”
The 5-ARIs include finasteride and dutasteride; the α-blockers include doxazocin, terazosin, tamsulosin, alfuzosin, silodosin, and naftopidil.
An MH, Kim MS, Kim C, et al. Association of 5α-reductase inhibitor prescription with bladder cancer progression in males in South Korea. JAMA Netw Open. Published online May 16, 2023. doi:10.1001/jamanetworkopen.2023.13667