Continued 5α-Reductase Inhibitor Use after Prostate Cancer Diagnosis and the Risk of Reclassification and Adverse Pathological Outcomes in the PASS

Nonsurgical Interventions to Prevent Disease Progression in Prostate Cancer Patients on Active Surveillance: A Systematic Review and Meta-analysis

CONTEXT

Active surveillance (AS) is a standard of care for patients with low-risk and selected intermediate-risk prostate cancer (PCa). Nevertheless, there is a lack of summary evidence on how to impact disease trajectory during AS.

OBJECTIVE

To assess which interventions prevent PCa progression effectively during AS.

EVIDENCE ACQUISITION

We queried PubMed, Scopus, and Web of Science databases to identify studies examining the impact of interventions aimed at slowing disease progression during AS. The primary endpoint was PCa progression, the definition of which must have included pathological upgrading. The secondary endpoint included treatment toxicities.

EVIDENCE SYNTHESIS

We identified 22 studies, six randomized controlled trials and 16 observational studies, which analyzed the association between different interventions and PCa progression during AS. The interventions considered in the studies included 5-alpha reductase inhibitors (5-ARIs), statins, diet, exercise, chlormadinone, fexapotide triflutate (FT), enzalutamide, coffee, vitamin D3, and PROSTVAC. We found that administration of 5-ARIs was associated with improved progression-free survival (PFS; hazard ratio: 0.59; 95% confidence interval 0.48-0.72), with no increased toxicity signals. Therapies such as vitamin D3, chlormadinone, FT, and enzalutamide have shown some efficacy. However, these anticancer drugs have been associated with treatment-related adverse events in up to 88% of patients.

CONCLUSIONS

The use of 5-ARIs in PCa patients on AS is associated with longer PFS. However, for the other interventions, it is difficult to draw clear conclusions based on the weak available evidence.

PATIENT SUMMARY

Patients with prostate cancer managed with active surveillance (AS) who are treated with 5-alpha reductase inhibitors have a lower risk of disease progression, with minimal adverse events. Other interventions require more studies to determine their efficacy and safety profile in men on AS.

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

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.

Prostate Cancer Risk and Prognostic Influence Among Users of 5-Alpha-Reductase Inhibitors and Alpha-Blockers: A Systematic Review and Meta-Analysis

We systematically assessed the effect of 5-alpha-reductase inhibitors (5-ARIs) and/or alpha-blockers use on prostate cancer (CaP) incidence and outcomes, including CaP pathologic progression, CaP-specific mortality, and all-cause mortality. 5-ARIs but not alpha-blockers decreased risk of overall CaP, low grade CaP (Gleason < 7), and delayed CaP pathologic progression. Both 5-ARIs and alpha-blockers had no significant impact on risk of high grade CaP (Gleason ≥ 7), CaP-specific mortality, or all-cause mortality. Our result suggested that finasteride should be given for at least 4 years if used for preventing CaP.

Prostate cancer patients can benefit from 5-alpha-reductase inhibitor treatment: a meta-analysis

Background

The efficacy and safety of 5α-reductase inhibitors (5ARIs) in treating prostate cancer (PCa) have not been fully determined. We performed a meta-analysis to evaluate the effectiveness and safety of 5ARIs for PCa patients.

Methods

A comprehensive literature search of online databases was conducted to obtain comparative studies exploring the effectiveness and safety of 5ARIs in treating PCa up to October 2019. Summarized odds ratio s (OR s) or hazard ratio s (HR s) were calculated to compare the outcomes between 5ARI and control groups. Our meta-analysis was registered in PROSPERO under number CRD42018109809.

Results

A total of 2,277 patients from 10 studies were included. No significant difference was found in prostate-specific antigen progression between two groups (OR = 0.82, 95% CI [0.52–1.29], P = 0.40). However, 5ARI treatment significantly reduced the total progression of PCa (OR = 0.61, 95% CI [0.48–0.77], P < 0.0001), especially for patients with local (OR = 0.56, 95% CI [0.44–0.73], P < 0.00001) and low-Gleason score (≤7) PCa (OR = 0.63, 95% CI [0.48–0.84], P = 0.002). Additionally, 5ARIs also significantly prolonged the progression-free survival time (HR = 0.57, 95% CI [0.34–0.96], P = 0.04) for PCa patients. No significant difference was found in the occurrence of PCa recurrence, metastasis, biopsy reclassification, and side-effects between two groups.

Conclusions

Our study suggests that 5ARI treatment can benefit patients with local and low Gleason score (≤7) PCa, especially in delaying the disease progression. More studies with larger sample size and comprehensive study design are still needed to verify our outcomes.