Association of Treatment With 5α-Reductase Inhibitors and Prostate Cancer Mortality Among Older Adults

Association Between 5α-Reductase Inhibitors and Prostate Cancer Mortality: A Systematic Review and Meta-analysis

Importance

Recently, several large, high-quality analyses have shown opposing results regarding the association between 5α-reductase inhibitor (5-ARI) use and prostate cancer (PCa) mortality.

Objective

To systematically evaluate the current evidence regarding 5-ARI use and PCa mortality.

Data Sources

A literature search began in and was conducted through August 2022 using PubMed/Medline, Embase, and Web of Science databases.

Study Selection

Studies were deemed eligible if they included male patients of any age who were 5-ARI users and were compared with those who were nonusers if they analyzed PCa mortality in randomized clinical trials and prospective or retrospective cohort studies.

Data Extraction and Synthesis

This study was reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Adjusted hazard ratios (HRs) were extracted from published articles. Data analysis was performed in August 2022.

Main Outcomes and Measures

The primary outcome was PCa mortality among 5-ARI users vs nonusers. The inverse variance method with adjusted HRs and random-effect models were used to determine the association between 5-ARI use and PCa mortality. Two subgroup analyses were performed to assess the effect of 2 main confounders: prostate-specific antigen level and PCa diagnosis at baseline.

Results

Among 1200 unique records screened, 11 studies met the inclusion criteria. A total of 3 243 575 patients were included: 138 477 users of 5-ARI and 3 105 098 nonusers. There was no statistically significant association between 5-ARI use and PCa mortality (adjusted HR, 1.04; 95% CI, 0.80-1.35; P = .79). No significant association was found when the analysis was restricted to studies that excluded patients with a diagnosis of PCa at baseline (adjusted HR, 1.00; 95% CI, 0.60-1.67; P = .99) or the analysis was restricted to prostate-specific antigen-adjusted studies (adjusted HR, 0.76; 95% CI, 0.57-1.03; P = .08).

Conclusions and Relevance

This systematic review and meta-analysis, which draws on 2 decades of epidemiologic literature and includes more than 3 million patients, found no statistically significant association between 5-ARI use and PCa mortality but provides important data to inform clinical care.

Association of 5α-Reductase Inhibitor Prescription With Bladder Cancer Progression in Males in South Korea

Importance

The antiandrogenic effect of the 5α-reductase inhibitor (5-ARI) has been investigated for its role in preventing male-predominant cancers. Although 5-ARI has been widely associated with prostate cancer, its association with urothelial bladder cancer (BC), another cancer experienced predominantly by males, has been less explored.

Objective

To assess the association between 5-ARI prescription prior to BC diagnosis and reduced risk of BC progression.

Design, Setting, and Participants

This cohort study analyzed patient claims data from the Korean National Health Insurance Service database. The nationwide cohort included all male patients with BC diagnosis in this database from January 1, 2008, to December 31, 2019. Propensity score matching was conducted to balance the covariates between 2 treatment groups: α-blocker only group and 5-ARI plus α-blocker group. Data were analyzed from April 2021 to March 2023.

Exposure

Newly dispensed prescriptions of 5-ARIs at least 12 months prior to cohort entry (BC diagnosis), with a minimum of 2 prescriptions filled.

Main Outcomes and Measures

The primary outcomes were the risks of bladder instillation and radical cystectomy, and the secondary outcome was all-cause mortality. To compare the risk of outcomes, the hazard ratio (HR) was estimated using a Cox proportional hazards regression model and difference in restricted mean survival time analysis.

Results

The study cohort initially included 22 845 males with BC. After propensity score matching, 5300 patients each were assigned to the α-blocker only group (mean [SD] age, 68.3 [8.8] years) and 5-ARI plus α-blocker group (mean [SD] age, 67.8 [8.6] years). Compared with the α-blocker only group, the 5-ARI plus α-blocker group had a lower risk of mortality (adjusted HR [AHR], 0.83; 95% CI, 0.75-0.91), bladder instillation (crude HR, 0.84; 95% CI, 0.77-0.92), and radical cystectomy (AHR, 0.74; 95% CI, 0.62-0.88). The differences in restricted mean survival time were 92.6 (95% CI, 25.7-159.4) days for all-cause mortality, 88.1 (95% CI, 25.2-150.9) days for bladder instillation, and 68.0 (95% CI, 31.6-104.3) days for radical cystectomy. The incidence rates per 1000 person-years were 85.59 (95% CI, 80.53-90.88) for bladder instillation and 19.57 (95% CI, 17.41-21.91) for radical cystectomy in the α-blocker only group and 66.43 (95% CI, 62.22-70.84) for bladder instillation and 13.56 (95% CI, 11.86-15.45) for radical cystectomy in the 5-ARI plus α-blocker group.

Conclusions and relevance

Results of this study suggest an association between prediagnostic prescription of 5-ARI and reduced risk of BC progression.

Detection of Prostate Cancer Using Biparametric Prostate MRI, Radiomics, and Kallikreins: A Retrospective Multicenter Study of Men With a Clinical Suspicion of Prostate Cancer

BACKGROUND

Accurate detection of clinically significant prostate cancer (csPCa), Gleason Grade Group ≥ 2, remains a challenge. Prostate MRI radiomics and blood kallikreins have been proposed as tools to improve the performance of biparametric MRI (bpMRI).

PURPOSE

To develop and validate radiomics and kallikrein models for the detection of csPCa.

STUDY TYPE

Retrospective.

POPULATION

A total of 543 men with a clinical suspicion of csPCa, 411 (76%, 411/543) had kallikreins available and 360 (88%, 360/411) did not take 5-alpha-reductase inhibitors. Two data splits into training, validation (split 1: single center, n = 72; split 2: random 50% of pooled datasets from all four centers), and testing (split 1: 4 centers, n = 288; split 2: remaining 50%) were evaluated.

FIELD STRENGTH/SEQUENCE

A 3 T/1.5 T, TSE T2-weighted imaging, 3x SE DWI.

ASSESSMENT

In total, 20,363 radiomic features calculated from manually delineated whole gland (WG) and bpMRI suspicion lesion masks were evaluated in addition to clinical parameters, prostate-specific antigen, four kallikreins, MRI-based qualitative (PI-RADSv2.1/IMPROD bpMRI Likert) scores.

STATISTICAL TESTS

For the detection of csPCa, area under receiver operating curve (AUC) was calculated using the DeLong's method. A multivariate analysis was conducted to determine the predictive power of combining variables. The values of P-value < 0.05 were considered significant.

RESULTS

The highest prediction performance was achieved by IMPROD bpMRI Likert and PI-RADSv2.1 score with AUC = 0.85 and 0.85 in split 1, 0.85 and 0.83 in split 2, respectively. bpMRI WG and/or kallikreins demonstrated AUCs ranging from 0.62 to 0.73 in split 1 and from 0.68 to 0.76 in split 2. AUC of bpMRI lesion-derived radiomics model was not statistically different to IMPROD bpMRI Likert score (split 1: AUC = 0.83, P-value = 0.306; split 2: AUC = 0.83, P-value = 0.488).

DATA CONCLUSION

The use of radiomics and kallikreins failed to outperform PI-RADSv2.1/IMPROD bpMRI Likert and their combination did not lead to further performance gains.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 2.

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.