Five-alpha reductase inhibitors in men undergoing active surveillance for prostate cancer: impact on treatment and reclassification after 6 years follow-up

Abstract

Objectives: To evaluate the impact of 5-alpha reductase inhibitors (5-ARIs) on definitive treatment (DT) and pathological progression (PP) in patients on active surveillance (AS) for prostate cancer.

Methods: We identified 361 consecutive patients, from an IRB-approved database, on AS for prostate cancer with minimum 2 years follow-up. Patients were grouped into two cohorts, those using 5-ARIs (5-ARI; n = 119) or not using 5-ARIs (no 5-ARI; n = 242). Primary and secondary endpoints were treatment-free survival (TFS) and PP-free survival (PPFS), which were evaluated by Kaplan-Meier analysis. Univariate and multivariable cox regression analysis were used to identify predictors for PP and DT. A p value < 0.05 was considered statistically significant.

Results: Baseline characteristics and the prostate biopsy rate were similar between the two groups. Median (range) follow-up was 5.7 (2.0-17.2) years. Five-year and 10-year TFS was 92% and 59% for the 5-ARI group versus 80% and 51% for the no 5-ARI group (p = 0.005), respectively. Five-year and 10-year PPFS was 77% and 41% for the 5-ARI group versus 70% and 32% for the no 5-ARI group (p = 0.04), respectively. Independent predictors for treatment and PP were not taking 5-ARIs (p = 0.005; p = 0.02), entry PSA > 2.5 ng/mL (p = 0.03; p = 0.01) and Gleason pattern 4 on initial biopsy (p < 0.001; p < 0.001), respectively. The main limitation is the retrospective study design.

Conclusions: 5-ARIs reduces reclassification and cross-over to treatment in men on active surveillance for prostate cancer. Further, taking 5-ARIs was an independent predictor for prostate cancer progression and definitive treatment.

Keywords: 5-alpha reductase inhibitor; Active surveillance; Chemoprevention; Prostate cancer.