Treatment with finasteride preserves usefulness of prostate-specific antigen in the detection of prostate cancer: results of a randomized, double-blind, placebo-controlled clinical trial. PLESS Study Group. Proscar Long-term Efficacy and Safety Study

Prostate Specific Antigen and Prostate Cancer in Gender Affirming Hormone Therapy for Transgender or Nonbinary Individuals

INTRODUCTION

The effects of gender affirming hormone therapy on prostate specific antigen (PSA) and prostate cancer incidence in transgender or non-binary individuals (TGNB) born with prostate glands remains uncharacterized.

METHODS

The cohort included 1,024 self-identified TGNB individuals assigned male at birth who received PSA testing in the VA Healthcare System, matched by birth year to cisgender men. PSA changes were measuring using linear-mixed effects modeling accounting for repeated measured and matching.

RESULTS

Non-gonadotrophin releasing hormone agonist or antagonist (GnRH) therapy was associated with 1.30 ng/mL lower PSA (95% confidence interval (CI) 1.14-1.46, p < 0.001) and GnRH therapy was associated with 1.08 ng/mL lower PSA (95% CI 0.60-1.55, p < 0.001) compared with cisgender men. Among 450 TGNB individuals who had PSA testing before and after initiation of hormone therapy, non-GnRH and GnRH therapies resulted in 0.49 ng/mL decrease (95% CI 0.35-0.62, p<0.001) and 0.73 ng/mL decrease (95% CI 0.43-1.02, p<0.001), respectively, from median baseline of 0.70 ng/mL. From time of age 50, TGNB prostate cancer incidence was 1.79 per 1,000 patient-years versus 4.02 per 1,000 patient-years in cisgender men.

CONCLUSIONS

Gender affirming hormone therapies are associated with significant decreases in PSA, and TGNB individuals assigned male at birth remain at risk for prostate cancer. Future work should establish if a lower threshold for biopsy should be used in these contexts and if the decreased incidence is a result of ascertainment bias or hormone therapy resulting in a true decrease in the incidence of prostate cancer.

An independent practice validation of the Prostate Imaging Reporting and Data System version 2 scoring system and the introduction of PDP (prostate-specific antigen density × PI-RADSv2) score to assist with further risk assessment

Objectives

To provide concise information to clinicians on how to better interpret multiparametric magnetic resonance imaging for prostate cancer risk stratification.

Materials and methods

We analyzed 2 separate cohorts. For patients receiving a Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) score of 1 or 2, we reviewed the charts of 226 patients who underwent multiparametric magnetic resonance imaging of the prostate ordered from 2015 to 2017 to determine who developed clinically significant prostate cancer (csPCa) by August 27, 2020. For patients receiving PI-RADSv2 a score of 3, 4, or 5, we reviewed the results of 733 fusion biopsies on solitary lesions. Statistical analysis was used to further determine risk factors for csPCa.

Results

Ten percent of men with PI-RADSv2 a score of 1 eventually developed csPCa. Seven percent with a score of 2 were eventually diagnosed with csPCa. Only 1 of 226 with a score of 1 or 2 developed metastasis. For PI-RADSv2 scores of 3, 4, and 5, csPCa was detected in 16%, 45%, and 67% of fusion biopsies. Peripheral zone (PZ) PI-RADSv2 score of 4 or 5 and prostate-specific antigen density (PSA-D) were significant predictors of csPCa on multivariable analysis. Using a PSA-D × PI-RADSv2 score of ≤0.39, we identified 38% of men with a PI-RADSv2 score of 3 in the PZ or 3, 4, or 5 in the transition zone who could have avoided a benign biopsy.

Conclusions

The vast majority of patients with PI-RADSv2 scores 1 and 2 can be safely monitored with close surveillance. Lesions with PI-RADSv2 scores of 4 and 5 in the PZ should be biopsied. Peripheral zone lesions with a PI-RADSv2 score of 3 and transition zone lesions with 3, 4, or 5 can be risk-stratified using the PSA-D × PI-RADSv2 score to determine who may safely avoid a biopsy and who should proceed to fusion biopsy.

5-Alpha Reductase Inhibitors and Prostate Cancer Mortality among Men with Regular Access to Screening and Health Care

BACKGROUND

How 5-alpha reductase inhibitor (5-ARI) use influences prostate cancer mortality is unclear. The objective of this study was to determine whether men taking 5-ARIs with regular health care access have increased prostate cancer mortality.

METHODS

We undertook two analyses in the Health Professionals Follow-up Study examining 5-ARI use, determined by biennial questionnaires, and prostate cancer. A cohort analysis followed 38,037 cancer-free men for prostate cancer incidence from 1996 through January 2017 and mortality through January 2019. A case-only analysis followed 4,383 men with localized/locally advanced prostate cancer for mortality over a similar period. HRs and 95% confidence intervals (CI) were calculated for prostate cancer incidence and mortality.

RESULTS

Men using 5-ARIs underwent more PSA testing, prostate exams and biopsies. Over 20 years of follow-up, 509 men developed lethal disease (metastases or prostate cancer death). Among men initially free from prostate cancer, 5-ARI use was not associated with developing lethal disease [HR, 1.02; 95% confidence interval (CI), 0.71-1.46], but was associated with reduced rates of overall and localized disease (HR, 0.71; 0.60-0.83). Among men diagnosed with prostate cancer, there was no association between 5-ARI use and cancer-specific (HR, 0.78; 95% CI, 0.48-1.27) or overall survival (HR, 0.88; 95% CI, 0.72-1.07).

CONCLUSIONS

Men using 5-ARIs were less likely to be diagnosed with low-risk prostate cancer, without increasing long-term risk of lethal prostate cancer or cancer-specific death after diagnosis.

IMPACT

Our results provide evidence that 5-ARI use is safe with respect to prostate cancer mortality in the context of regular health care access. See related commentary by Hamilton, p. 1259.

Association of 5α-Reductase Inhibitors With Prostate Cancer Mortality

Importance

There is evidence that 5α-reductase inhibitors (5-ARIs), a standard treatment of benign prostate hyperplasia, are associated with a decrease in the incidence of prostate cancer (PCa). However, studies to date have had conflicting results regarding the association with prostate cancer mortality (PCM).

Objective

To evaluate the association of treatment with 5-ARIs with PCM in men without a prior diagnosis of PCa.

Design, Setting, and Participants

This population-based cohort study was conducted in Stockholm, Sweden, between January 1, 2007, and December 31, 2018, and included 429 977 men with a prostate-specific antigen (PSA) test within the study period. Study entry was set to 1 year after the first PSA test. Data were analyzed from September 2021 to December 2021.

Exposures

After their initial PSA test, men with 2 or more newly dispensed prescriptions of 5-ARI, finasteride, or dutasteride were considered 5-ARI users (n = 26 190).

Main Outcomes and Measures

Primary outcome was PCM. Cox proportional hazards regression models were used to calculate multivariable-adjusted hazard ratios (HRs) and 95% CIs for all-cause mortality and PCM.

Results

The study cohort included 349 152 men. The median (IQR) age for those with 2 or more filled prescriptions of 5-ARI was 66 (61-73) years and 57 (50-64) years for those without. The median follow-up time was 8.2 (IQR, 4.9-10) years with 2 257 619 person-years for the unexposed group and 124 008 person-years for the exposed group. The median exposure to treatment with 5-ARI was 4.5 (IQR, 2.1-7.4) years. During follow-up, 35 767 men (8.3%) died, with 852 deaths associated with PCa. The adjusted multivariable survival analysis showed a lower risk of PCM in the 5-ARI group with longer exposure times (0.1-2.0 years: adjusted HR, 0.89; 95% CI, 0.64-1.25; >8 years: adjusted HR, 0.44; 95% CI, 0.27-0.74). No statistically significant differences were seen in all-cause mortality between the exposed and unexposed group. Men treated with 5-ARIs underwent more PSA tests and biopsies per year than the unexposed group (median of 0.63 vs 0.33 and 0.22 vs 0.12, respectively).

Conclusions and Relevance

The results of this cohort study suggest that there was no association between treatment with 5-ARI and increased PCM in a large population-based cohort of men without a previous PCa diagnosis. Additionally, a time-dependent association was seen with decreased risk of PCM with longer 5-ARI treatment. Further research is needed to determine whether the differences are because of intrinsic drug effects or PCa testing differences.

Lifestyle factors and prostate-specific antigen

Background:

Increasing prostate cancer awareness has meant that more men are seeking out prostate-specific antigen (PSA) testing than ever before. Prostate cancer is now the most common malignancy in men, affecting one in eight. This article addresses lifestyle factors that may elevate PSA readings.

Methods:

A systematic review of the literature was performed using Medline for studies examining the association of PSA and lifestyle factors, including exercise, diet, sexual function as well as medication use. Further resources were identified from the reference list of retrieved articles.

Results:

Minimal level 1 evidence on the association of PSA with lifestyle factors was identified. Weak and generally inconsistent evidence was found on the effect of cycling and sexual activity. Diabetes and obesity did have inversely proportional effects on PSA values in large cohort studies. There was no evidence for an independent effect of different types of food to PSA. With regard to medications, the greatest impact is from 5-alpha reductase inhibitors, and these are used as a hair-loss treatment. Statins, non-steroidal anti-inflammatory drugs and thiazide diuretics can also have a clinically significant impact on PSA levels but unlikely to alter management.

Discussion:

For a small group of patients, cautious counselling on the factors summarised here before they have their blood tests may prevent undue stress and anxiety, particularly in those with borderline PSA results. Due to the inconsistency of results and lack of level 1a evidence, if there is reasonable suspicion for prostate cancer, a patient should still always be referred to a specialist.

Level of evidence:

Level 4.

Prostate-specific antigen density during dutasteride treatment for 1 year predicts the presence of prostate cancer in benign prostatic hyperplasia after the first negative biopsy (PREDICT study)

OBJECTIVES

To prospectively evaluate the detection rate of prostate cancer, and to identify the risk factors of prostate cancer detection after a 1-year administration of dutasteride and first negative prostate biopsy.

METHODS

Patients with benign prostatic hyperplasia who presented high prostate-specific antigen levels after the first negative prostate biopsy were administered 0.5 mg dutasteride daily for 1 year. They underwent a repeat prostate biopsy after 1 year. The primary end-point was the detection rate of prostate cancer. The secondary end-point was the ability of prostate-specific antigen kinetics to predict prostate cancer detection. Prostate-specific antigen was measured before the initial prostate biopsy and at 6, 9 and 12 months after starting dutasteride. Patients were classified into a prostate cancer and a non-prostate cancer group.

RESULTS

Prostate cancer was detected in 15 of 149 participants (10.1%). The total prostate-specific antigen change between the prostate cancer and non-prostate cancer group at 1 year was significantly different (P = 0.002). Although prostate-specific antigen levels at baseline did not significantly differ between study groups (P = 0.102), prostate-specific antigen levels at 6, 9 and 12 months were significantly different (P = 0.002, P = 0.001 and P < 0.001, respectively). The mean reduction rate of prostate-specific antigen density between the prostate cancer and non-prostate cancer group at 1 year was significantly different (-4.25 ± 76.5% vs -38.0 ± 28.7%, P = 0.001). Using a multivariate analysis, a >10% increase of prostate-specific antigen density at 1 year post-dutasteride treatment was the only predictive risk factor for prostate cancer after the first negative prostate biopsy (odds ratio 11.238, 95% confidence interval 3.112-40.577, P < 0.001).

CONCLUSION

In the present study cohort, >10% increase in prostate-specific antigen density represented the only significant predictive risk factor for prostate cancer diagnosis in patients with elevated prostate-specific antigen after the first negative prostate biopsy.

Detection of TMPRSS2-ERG Fusion Transcript in Biopsy Specimen of Prostate Cancer Patients: A Single Centre Experience

INTRODUCTION

Prostate carcinoma is the most frequent malign neoplasm among men with an ever-growing incidence rate. TMPRSS2-ERG fusion transcript leads to the androgen induction of ERG proto-oncogenes expression, representing a high presence of oncogenes alteration among prostate tumour cells.

AIM

The aim of this research was to detect and evaluate theTMPRSS2-ERG fuse transcript in the tissues of patients with prostate cancer, and establish a base of material of these samples for further genetic examination.

MATERIALS AND METHODS

The research was a prospective clinical study that involved and focused on random sampling of 101 patients (62 with prostate cancer-study group and 39 with benign changes in the prostate-control group). Real time PCR analysis for detection of the TMPRSS2-ERG fusion transcript in prostate tissue was performed and also data from the histopathology results of tissues were used, as well as data for the level of PSA (prostate-specific antigen) in blood.

RESULTS

TMPRSS2-ERG fusion transcript was detected in 20 out of 62 (32.2%) patients with prostate carcinoma and among no patients with benign changes whatsoever. There were no significant differences between patients with/without detected TMPRSS2-ERG fusion related to Gleason score. Among 50%, in the study group this score was greater than 7 per/for Median IQR=7 (6-8). Significant difference was recognized, related to the average value of PSA in favour of significantly higher value of PSA in the study group with prostate cancer, but there was also no significant difference between samples with prostate cancer who were with/without detected TMPRSS2-ERG fusion transcript related to PSA level.

DISCUSSION

The results from this research are in accordance with the values and results from analyses done in several research centres and oncological institutes.

CONCLUSION

The positive findings in small scale studies encourage the implementation of larger scale studies that will be enriched with results of genetic transcript in blood and urine and will define the positive diagnostic meaning of the TMPRSS-ERG fusion transcript.

Association of 5-alpha-reductase inhibitor and prostate cancer incidence and mortality: a meta-analysis

Background

5-Alpha-reductase inhibitors (5-ARIs) have been suggested as potential chemopreventive agents for prostate cancer (PCa). This study was conducted to evaluate the effect of 5-ARIs on the incidence and mortality of PCa.

Methods

The PubMed, Embase and Cochrane Library databases were searched comprehensively from database inception to October 2019. The clinical outcomes included the incidence of overall PCa, high-grade (Gleason8-10) PCa, metastatic PCa, overall survival (OS), and cancer-specific survival (CSS).

Results

Overall, 23 studies were included in the present study, representing 11 cohort studies, 5 case-control studies, and 8 randomized controlled trials. The use of 5-ARIs was associated with a decreased risk of overall PCa [relative risk (RR) =0.77; 95% CI: 0.67–0.88; P<0.001] and increased risk of Gleason 8–10 PCa (RR=1.19; 95% CI: 1.01–1.40; P=0.036). In terms of metastatic PCa, there were no significant between-group differences (RR=1.23; 95% CI: 0.69–2.18; P=0.487). Furthermore, we found that prediagnostic 5-ARI usage was not associated with an increased risk of overall or prostate cancer mortality, with HRs of 1.00 (95% CI: 0.92–1.08; P=0.938) and 0.98 (95% CI: 0.80–1.21; P=0.881), respectively.

Conclusions

In conclusion, while male 5-ARI users were associated with a decreased risk of overall prostate cancer and increased risk of high-grade prostate cancer (Gleason 8–10), they were not associated with an increased risk of overall or prostate cancer mortality. 5-ARIs should be recommended carefully for use as chemopreventive agents.

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.

Post-finasteride syndrome: a surmountable challenge for clinicians

Post-finasteride syndrome (PFS) is a constellation of serious adverse side effects manifested in clinical symptoms that develop and persist in patients during and/or after discontinuing finasteride treatment in men with pattern hair loss (androgenetic alopecia) or benign prostatic hyperplasia. These serious adverse side effects include persistent or irreversible sexual, neurological, physical and mental side effects. To date, there are no evidence-based effective treatments for PFS. Although increasing number of men report persistent side effects, the medical community has yet to recognize this syndrome nor are there any specific measures to address this serious and debilitating symptoms. Here we evaluate the scientific and clinical evidence in the contemporary medical literature to address the very fundamental question: Is PFS a real clinical condition caused by finasteride use or are the reported symptoms only incidentally associated with but not caused by finasteride use? One key indisputable clinical evidence noted in all reported studies with finasteride and dutasteride was that use of these drugs is associated with development of sexual dysfunction, which may persist in a subset of men, irrespective of age, drug dose or duration of study. Also, increased depression, anxiety and suicidal ideation in a subset of men treated with these drugs were commonly reported in a number of studies. It is important to note that many clinical studies suffer from incomplete or inadequate assessment of adverse events and often limited or inaccurate data reporting regarding harm. Based on the existing body of evidence in the contemporary clinical literature, the author believes that finasteride and dutasteride induce a constellation of persistent sexual, neurological and physical adverse side effects, in a subset of men. These constellations of symptoms constitute the basis for PFS in individuals predisposed to epigenetic susceptibility. Indeed, delineating the pathophysiological mechanisms underlying PFS will be of paramount importance to the understanding of this syndrome and to development of potential novel therapeutic modalities.

The impact of 5-alpha-reductase inhibitors on mortality in a prostate cancer chemoprevention setting: a meta-analysis

PURPOSE

This study aims to evaluate the impact of 5-alpha-reductase inhibitors (5ARI) for prostate cancer (PCa) primary prevention on specific and overall mortality (primary outcomes), the incidence of PCa diagnosis and disease aggressiveness (secondary outcomes).

METHODS

We searched MEDLINE, EMBASE, Cochrane, ClinicalTrials and BVS through April 2018 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement to identify randomized clinical trials (RCT) and cohort studies (CS). We included articles with data on mortality or PCa incidence for men using 5ARI previously to PCa diagnosis.

RESULTS

Regarding the included studies, nine had data on mortality, 16 on PCa incidence and 12 on Gleason scores (GS). We found that the use of 5ARI had no impact on overall mortality (RR 0.93 95% CI 0.78-1.11) and PCa-related mortality (RR 1.35 95% CI 0.50-3.94), nor on high-grade PCa diagnosis (RR 1.06 95% CI 0.72-1.56). We identified a relative risk reduction of 24% in moderate-grade PCa diagnosis (RR 0.76 95% CI 0.59-0.98) and low-grade PCa diagnosis (RR 0.76 95% CI 0.59-0.97) Also, a reduction of 26% in overall PCa diagnosis was observed in the RCT subgroup analysis (RR 0.74 95% CI 0.65-0.84).

CONCLUSION

5ARI significantly reduced the risk of being diagnosed with PCa, not increasing high-grade disease, overall or cancer-specific mortality. Due to the relatively short mean follow-up of most studies, the mortality analysis is limited.

High Real-World Medication Adherence and Durable Clinical Benefit in Medicare Patients Treated with 5-Alpha Reductase Inhibitors for Benign Prostatic Hyperplasia

PURPOSE

Although clinical trials demonstrate 5-alpha reductase inhibitors are efficacious treatments for benign prostatic hyperplasia, they have low reported medication adherence outside of clinical trials. We evaluated real-world drug adherence and clinical outcomes in Medicare patients with lower urinary tract symptoms from benign prostatic hyperplasia managed with 5-alpha reductase inhibitor therapy.

MATERIALS AND METHODS

Using health care and pharmacy claims from Partners Healthcare Medicare Accountable Care Organization enrollees (January 2009 to July 2018), we identified men initiating a 5-alpha reductase inhibitor for benign prostatic hyperplasia with more than 1 medication dispensation. Adherence was calculated as an 80% or greater proportion of days covered. A Cox proportional hazards model was used to evaluate the primary outcome of treatment failure, defined as any benign prostatic hyperplasia related surgery.

RESULTS

Among 3,107 men initiating 5-alpha reductase inhibitor therapy for benign prostatic hyperplasia and filling at least 2 prescriptions, 74.9% had high medication adherence during the first year. Patients with low adherence had 29% higher hazards of undergoing surgical intervention (95% CI 1.02-1.59, p=0.036) after adjusting for age, benign prostatic hyperplasia severity, presence of hematuria, bladder stones and type of 5-alpha reductase inhibitors. The presence of bladder stones (HR 1.70, 95% CI 1.02-2.86, p=0.04) and finasteride vs dutasteride use (HR 1.41, 95% CI 1.01-1.98, p=0.05) were also risk factors for surgical intervention.

CONCLUSIONS

Among Medicare patients 5-alpha reductase inhibitor treatment adherence was high and associated with lower hazards of surgical intervention. 5-Alpha reductase inhibitor therapy may be more feasible for older men with benign prostatic hyperplasia than previously reported and demonstrates modest clinical benefit.

Methylation of SRD5A2 promoter predicts a better outcome for castration-resistant prostate cancer patients undergoing androgen deprivation therapy

PURPOSE

To determine whether SRD5A2 promoter methylation is associated with cancer progression during androgen deprivation therapy (ADT) in CRPC.

PATIENTS AND METHODS

In a Local CRPC cohort, 42 prostatic specimens were collected from patients who were diagnosed as CRPC and underwent transurethral resection of the prostate (TURP) at Massachusetts General Hospital (MGH). In a metastatic CRPC (Met CRPC) cohort, 12 metastatic biopsies were collected from CRPC patients who would be treated with abiraterone plus dutasteride (Clinical Trial NCT01393730). As controls, 36 benign prostatic specimens were collected from patients undergoing prostate reduction surgery for symptoms of bladder outlet obstruction secondary to benign prostatic hyperplasia (BPH). The methylation status of cytosine-phosphate-guanine (CpG) site(s) at SRD5A2 promoter regions was tested.

RESULTS

Compared with benign prostatic tissue, CRPC samples demonstrated higher SRD5A2 methylation in the whole promoter region (Local CRPC cohort: P < 0.001; Met CRPC cohort: P <0.05). In Local CRPC cohort, a higher ratio of methylation was correlated with better OS (R2 = 0.33, P = 0.013). Hypermethylation of specific regions (nucleotides -434 to -4 [CpG# -39 to CpG# -2]) was associated with a better OS (11.3±5.8 vs 6.4±4.4 years, P = 0.001) and PFS (8.4±5.4 vs 4.5±3.9 years, P = 0.003) with cutoff value of 37.9%. Multivariate analysis showed that SRD5A2 methylation was associated with OS independently (whole promoter region: P = 0.035; specific region: P = 0.02).

CONCLUSION

Our study demonstrate that SRD5A2 methylation in promoter regions, specifically at CpG# -39 to -2, is significantly associated with better survival for CRPC patients treated with ADT. Recognition of epigenetic modifications of SRD5A2 may affect the choices and sequence of available therapies for management of CRPC.

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

This cohort study examines the association between use of 5α-reductase inhibitors and prostate cancer mortality among US Medicare beneficiaries.

Association of Treatment With 5α-Reductase Inhibitors With Time to Diagnosis and Mortality in Prostate Cancer

IMPORTANCE

5α-Reductase inhibitors (5-ARIs), commonly used to treat benign prostatic hyperplasia, reduce serum prostate-specific antigen (PSA) concentrations by 50%. The association of 5-ARIs with detection of prostate cancer in a PSA-screened population remains unclear.

OBJECTIVE

To test the hypothesis that prediagnostic 5-ARI use is associated with a delayed diagnosis, more advanced disease at diagnosis, and higher risk of prostate cancer-specific mortality and all-cause mortality than use of other or no PSA-decreasing drugs.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study linked the Veterans Affairs Informatics and Computing Infrastructure with the National Death Index to obtain patient records for 80 875 men with American Joint Committee on Cancer stage I-IV prostate cancer diagnosed from January 1, 2001, to December 31, 2015. Patients were followed up until death or December 31, 2017. Data analysis was performed from March 2018 to May 2018.

EXPOSURES

Prediagnostic 5-ARI use.

MAIN OUTCOMES AND MEASURES

The primary outcome was prostate cancer-specific mortality (PCSM). Secondary outcomes included time from first elevated PSA (defined as PSA≥4 ng/mL) to diagnostic prostate biopsy, cancer grade and stage at time of diagnosis, and all-cause mortality (ACM). Prostate-specific antigen levels for 5-ARI users were adjusted by doubling the value, consistent with previous clinical trials.

RESULTS

Median (interquartile range [IQR]) age at diagnosis was 66 (61-72) years; median [IQR] follow-up was 5.90 (3.50-8.80) years. Median time from first adjusted elevated PSA to diagnosis was significantly greater for 5-ARI users than 5-ARI nonusers (3.60 [95% CI, 1.79-6.09] years vs 1.40 [95% CI, 0.38-3.27] years; P < .001) among patients with known prostate biopsy date. Median adjusted PSA at time of biopsy was significantly higher for 5-ARI users than 5-ARI non-users (13.5 ng/mL vs 6.4 ng/mL; P < .001). Patients treated with 5-ARI were more likely to have Gleason grade 8 or higher (25.2% vs 17.0%; P < .001), clinical stage T3 or higher (4.7% vs 2.9%; P < .001), node-positive (3.0% vs 1.7%; P < .001), and metastatic (6.7% vs 2.9%; P < .001) disease than 5-ARI nonusers. In a multivariable regression, patients who took 5-ARI had higher prostate cancer-specific (subdistribution hazard ratio [SHR], 1.39; 95% CI, 1.27-1.52; P < .001) and all-cause (HR, 1.10; 95% CI, 1.05-1.15; P < .001) mortality.

CONCLUSIONS AND RELEVANCE

Results of this study demonstrate that prediagnostic use of 5-ARIs was associated with delayed diagnosis and worse cancer-specific outcomes in men with prostate cancer. These data highlight a continued need to raise awareness of 5-ARI-induced PSA suppression, establish clear guidelines for early prostate cancer detection, and motivate systems-based practices to facilitate optimal care for men who use 5-ARIs.

Impact of 5α-reductase inhibitor and α-blocker therapy for benign prostatic hyperplasia on prostate cancer incidence and mortality

OBJECTIVE

To investigate the use of 5α-reductase inhibitors (5ARIs) and α-blockers among men with benign prostatic hyperplasia (BPH) in relation to prostate cancer (PCa) incidence, severity and mortality.

PATIENTS AND METHODS

A retrospective 20-year cohort study in men residing in Saskatchewan, aged 40-89 years, with a BPH-coded medical claim between 1995 and 2014, was conducted. Cox proportional hazards regression was used to compare incidence of PCa diagnosis, metastatic PCa, Gleason score 8-10 PCa, and PCa mortality among 5ARI users (n = 4 571), α-blocker users (n = 7 764) and non-users (n = 11 677).

RESULTS

In comparison with both non-users and α-blocker users, 5ARI users had a ~40% lower risk of a PCa diagnosis (11.0% and 11.4% vs 5.8%, respectively), and α-blocker users had an 11% lower risk of a PCa diagnosis compared with non-users. Overall, the incidence of metastatic PCa and PCa mortality was not significantly different among 5ARI or α-blocker users compared with non-users (adjusted hazard ratios [HR] of metastatic PCa: 1.12 and 1.13, respectively, and PCa mortality: 1.11 and 1.18, respectively, P > 0.05 for both drugs), but both 5ARI and a-blocker users had ~30% higher risk of Gleason score 8-10 cancer, adjusted HR 1.37, 95% confidence interval [CI] 1.03-1.82, P = 0.03, and adjusted HR 1.28, 95% CI 1.03-1.59, P = 0.02, respectively compared with non-users.

CONCLUSION

The use of 5ARIs was associated with lower risk of PCa diagnosis, regardless of comparison group. Risk of high grade PCa was higher among both 5ARI users and α-blocker users compared with non-users; however, this did not translate into higher risk of PCa mortality.

Drugs for benign prostatic hypertrophy

Benign prostatic hyperplasia is a common condition It can cause problems with urine storage and voiding and the severity of symptoms may be unrelated to the size of the prostate

When drug treatment is required benign prostatic hyperplasia can be managed with monotherapy or combination therapy Most patients are managed with selective alpha blockers

Patients with larger prostate volumes may benefit from a 5-alpha-reductase inhibitor usually in combination with an alpha blocker

Correlation between 5-α reductase type 2 protein expression and methylation of 5-α reductase type 2 promotor gene of benign prostatic hyperplasia

PURPOSE

The enzyme 5-α reductase type 2 (5-AR 2) plays a key role in the development and maintenance of the prostate gland. We evaluated the level 5-AR 2 protein expression and the relationship between methylation of the 5-AR 2 gene-promoter and 5-AR 2 protein expression of benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A total of 37 prostate samples were evaluated. These included 22 samples from men undergoing transurethral prostate resections and 15 non-cancerous transition-zone human prostate tissue samples taken following radical prostatectomy. We quantified 5-AR 2 protein expression and gene-promoter methylation status using common assay procedures. Clinical variables included age, body mass index (BMI), prostate-specific antigen (PSA) levels, lipid profiles, and prostate volumes. Univariate and multivariate statistical analyses were performed followed by stepwise logistic regression modeling.

RESULTS

We were able to extract DNA from 36 of the 37 tissue samples and 10 of these (28%) did not express the 5-AR 2 protein. In total, 26 patients (72%) had methylated 5-AR 2 promoter-regions. There was a strong correlation between methylation of the 5-AR 2 promoter-regions and low-absent 5-AR 2 protein expression (p = 0.0003). Increasing age significantly predicted methylation status and protein expression level (p = 0.013).

CONCLUSIONS

The level of 5-AR 2 protein expression varies among prostate tissue samples. Methylation of the 5-AR 2 gene-promoter may account for low or absent expression of 5-AR 2 in adult human prostate tissues. Increased age correlates with increased 5-AR 2 gene-promoter methylation and decreased protein expression in men with BPH.

Prostate-Specific Antigen Kinetics Following 5α-Reductase Inhibitor Treatment May Be a Useful Indicator for Repeat Prostate Biopsy

PURPOSE

To evaluate parameters for determining repeat prostate biopsy in patients with 5α-reductase inhibitor (5ARI) treatment after initial negative biopsy.

MATERIALS AND METHODS

From January 2007 to December 2015, patients who underwent a repeat prostate biopsy after an initial negative biopsy were enrolled from multiple institutions. Serial prostate-specific antigen (PSA) levels after the initial biopsy were analyzed for PSA kinetics. Clinicopathologic variables were evaluated according to the use of 5ARIs after the initial negative biopsy.

RESULTS

Of 419 patients with initial negative biopsies (median age=67.0 years, median PSA=6.31 ng/mL), 101 patients (24.1%) were diagnosed with prostate cancer at the repeat biopsy. An increase in PSA level at 18 months, compared to that at 6 months, was a predictor of a positive repeat biopsy. However, the use of 5ARIs was not identified as a predictor. Of 126 patients receiving 5ARI treatment after the initial biopsy, 30 (23.8%) were diagnosed with prostate cancer at the repeat biopsy. Increase in PSA level at more than two time points after 6 months of 5ARI treatment (odds ratio=4.84, p=0.005) was associated with cancer detection at the repeat biopsy. There were no significant 5ARI group-related differences in the detection rates of prostate and high-grade cancers (Gleason score ≥7).

CONCLUSION

The effects of 5ARIs on prostate cancer detection and chemoprevention remain uncertain. However, more than two increases in PSA level after 6 months of 5ARI treatment may indicate the presence of prostate cancer.

Androgenic to oestrogenic switch in the human adult prostate gland is regulated by epigenetic silencing of steroid 5α-reductase 2

Benign prostatic hyperplasia is the most common proliferative abnormality of the prostate. All men experience some prostatic growth as they age, but the rate of growth varies among individuals. Steroid 5α-reductase 2 (SRD5A2) is a critical enzyme for prostatic development and growth. Previous work indicates that one-third of adult prostatic samples do not express SRD5A2, secondary to epigenetic modifications. Here we show that the level of oestradiol is dramatically elevated, concomitant with significant upregulation of oestrogen response genes, in prostatic samples with methylation at the SRD5A2 promoter. The phosphorylation of oestrogen receptor-α in prostatic stroma is upregulated when SRD5A2 expression is absent. We show that tumour necrosis factor (TNF)-α suppresses SRD5A2 mRNA and protein expression, and simultaneously promotes expression of aromatase, the enzyme responsible for conversion of testosterone to oestradiol. Concomitant suppression of SRD5A2 and treatment with TNF-α synergistically upregulate the aromatase levels. The data suggest that, in the absence of prostatic SRD5A2, there is an androgenic to oestrogenic switch. These findings have broad implications for choosing appropriate classes of medications for the management of benign and malignant prostatic diseases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Adverse effects of 5α-reductase inhibitors: What do we know, don't know, and need to know?

Steroids are important physiological orchestrators of endocrine as well as peripheral and central nervous system functions. One of the key processes for regulation of these molecules lies in their enzymatic processing by a family of 5α-reductase (5α-Rs) isozymes. By catalyzing a key rate-limiting step in steroidogenesis, this family of enzymes exerts a crucial role not only in the physiological control but also in pathological events. Indeed, both 5α-R inhibition and supplementation of 5α-reduced metabolites are currently used or have been proposed as therapeutic strategies for a wide array of pathological conditions. In particular, the potent 5α-R inhibitors finasteride and dutasteride are used in the treatments of benign prostatic hyperplasia (BPH), as well as in male pattern hair loss (MPHL) known as androgenetic alopecia (AGA). Recent preclinical and clinical findings indicate that 5α-R inhibitors evoke not only beneficial, but also adverse effects. Future studies should investigate the biochemical and physiological mechanisms that underlie the persistence of the adverse sexual side effects to determine why a subset of patients is afflicted with such persistence or irreversible adverse effects. Also a better focus of clinical research is urgently needed to better define those subjects who are likely to be adversely affected by such agents. Furthermore, research on the non-sexual adverse effects such as diabetes, psychosis, depression, and cognitive function are needed to better understand the broad spectrum of the effects these drugs may elicit during their use in treatment of AGA or BPH. In this review, we will summarize the state of art on this topic, overview the key unresolved questions that have emerged on the pharmacological targeting of these enzymes and their products, and highlight the need for further studies to ascertain the severity and duration of the adverse effects of 5α-R inhibitors, as well as their biological underpinnings.

DNA methyl transferase 1 reduces expression of SRD5A2 in the aging adult prostate

5-α Reductase type 2 (SRD5A2) is a critical enzyme for prostatic development and growth. Inhibition of SRD5A2 by finasteride is used commonly for the management of urinary obstruction caused by benign prostatic hyperplasia. Contrary to common belief, we have found that expression of SRD5A2 is variable and absent in one third of benign adult prostates. In human samples, absent SRD5A2 expression is associated with hypermethylation of the SRD5A2 promoter, and in vitro SRD5A2 promoter activity is suppressed by methylation. We show that methylation of SRD5A2 is regulated by DNA methyltransferase 1, and inflammatory mediators such as tumor necrosis factor α, NF-κB, and IL-6 regulate DNA methyltransferase 1 expression and thereby affect SRD5A2 promoter methylation and gene expression. Furthermore, we show that increasing age in mice and humans is associated with increased methylation of the SRD5A2 promoter and concomitantly decreased protein expression. Artificial induction of inflammation in prostate primary epithelial cells leads to hypermethylation of the SRD5A2 promoter and silencing of SRD5A2, whereas inhibition with tumor necrosis factor α inhibitor reactivates SRD5A2 expression. Therefore, expression of SRD5A2 is not static and ubiquitous in benign adult prostate tissues. Methylation and expression of SRD5A2 may be used as a gene signature to tailor therapies for more effective treatment of prostatic diseases.

Prevention and early detection of prostate cancer

Prostate cancer is a common malignancy in men and the worldwide burden of this disease is rising. Lifestyle modifications such as smoking cessation, exercise, and weight control offer opportunities to reduce the risk of developing prostate cancer. Early detection of prostate cancer by prostate-specific antigen (PSA) screening is controversial, but changes in the PSA threshold, frequency of screening, and the use of other biomarkers have the potential to minimise the overdiagnosis associated with PSA screening. Several new biomarkers for individuals with raised PSA concentrations or those diagnosed with prostate cancer are likely to identify individuals who can be spared aggressive treatment. Several pharmacological agents such as 5α-reductase inhibitors and aspirin could prevent development of prostate cancer. In this Review, we discuss the present evidence and research questions regarding prevention, early detection of prostate cancer, and management of men either at high risk of prostate cancer or diagnosed with low-grade prostate cancer.

Prostate cancer chemoprevention

Prostate cancer is a leading cause of morbidity and mortality in men and has significant treatment-associated complications. Prostate cancer chemoprevention has the potential to decrease the morbidity and mortality associated with this disease. Chemoprevention research to date has primarily focused on nutrients and 5 alpha-reductase inhibitors (5ARIs). A large randomized trial (SELECT) found no favorable effect of selenium or vitamin E on prostate cancer prevention. Two large randomized placebo controlled trials (the PCPT and REDUCE trials) have been published and have supported the role of 5ARIs in prostate cancer chemoprevention; however, these trials also have prompted concerns regarding the increase in high-grade disease seen with treatment and have not been approved by the US Food and Drug Administration (FDA) for chemoprevention. Conclusive evidence for the chemopreventive benefit of nutrients or vitamins is lacking, whereas the future role of 5ARIs remains to be clarified.

Screening for prostate cancer: an updated review

Prostate cancer is the most frequently diagnosed malignancy in men and its incidence has been increasing in the last decades. Diagnosis and treatment of prostate cancer were radically improved after the discovery of prostatic-specific antigen. Early detection rates increased, especially in asymptomatic individuals, confirmed by recent published randomized trials. The impact of screening in overdiagnosis and overtreatments is discussed, since benefits in overall mortality rates were not clearly demonstrated. Perhaps younger patients with a longer life expectancy would be the ones with the most benefits from screening. This study presents an update of the most important screening methods for prostate cancer as well as the recent recommendations for screening.

Drug-induced gynecomastia

Drugs account for about 20% of gynecomastia cases in men. As a number of factors can alter the estrogen:androgen ratio, several pathophysiologic mechanisms are associated with drugs causing this disorder. Antiandrogens, protease inhibitors, and nucleoside reverse transcriptase inhibitors are the most common drug causes of gynecomastia, whereas first-generation antipsychotics, spironolactone, verapamil, and cimetidine are less common causes. Other drugs have been reported rarely as causes. Treatment may involve switching to an alternative agent or may require surgery or irradiation if the causative agent cannot be discontinued. We reviewed the literature on drug-induced gynecomastia and provided another perspective by reviewing data from the United States Food and Drug Administration's Adverse Event Reporting System. Epidemiologic studies are needed to provide a more accurate description of the frequency of drug-induced gynecomastia.

Prostate biopsy in response to a change in nadir prostate specific antigen of 0.4 ng/ml after treatment with 5α-reductase inhibitors markedly enhances the detection rate of prostate cancer

PURPOSE

We examined the effect of 5α-reductase inhibitor therapy on prostate cancer detection in men with persistently increased or fluctuating prostate specific antigen and prior negative prostate cancer biopsy.

MATERIALS AND METHODS

A total of 276 men with prostate specific antigen greater than 4 ng/ml (208) or a prostate specific antigen velocity change of 0.75 ng/ml (68) and a normal digital rectal examination who had previously undergone biopsy a minimum of 2 times with prostate cancer not detected were given 5 mg finasteride (154) or dutasteride (122) daily. In phase 1, 97 patients had prostate specific antigen measured at 6 and 12 months with repeat transrectal ultrasonography and biopsy (12 cores) performed at 1 year. In phase 2, 179 patients underwent biopsy triggered by a change in nadir prostate specific antigen of more than 0.4 ng/ml.

RESULTS

In phase 1 at 1 year prostate specific antigen had decreased by 2.4 ng/ml (-46.7%), and prostate volume had decreased 7.1 ml (-17.9%). Prostate cancer was detected in 27 of 97 (27.8%) patients and the mean minimum prostate specific antigen velocity from a nadir of 0.4 ng/ml was 0.6 ng/ml. In phase 2, 48 of 179 (26.8%) men underwent repeat biopsy at a mean of 14.6 months. Of these 48 men 26 (54.1%) were found to have prostate cancer. Of the 26 men in whom prostate cancer was detected 20 (76.9%) were found to have Gleason score 7 or greater disease.

CONCLUSIONS

The magnitude of change in serum prostate specific antigen after 5α-reductase inhibitor therapy may be useful in diagnosing prostate cancer in patients with persistently increased or fluctuating prostate specific antigen and prior negative prostate biopsy.

A population-based nested case-control study in taiwan: use of 5α-reductase inhibitors did not decrease prostate cancer risk in patients with benign prostate hyperplasia

BACKGROUND

5α-Reductase inhibitors (5ARIs) are commonly used to treat benign prostate hyperplasia (BPH) by blocking the conversion of testosterone into the more potent dihydrotestosterone. This study explored a possible association between the use of the 5ARIs finasteride and dutasteride and the subsequent risk of prostate cancer or other cancers.

METHODS

We analyzed data from the Taiwanese National Health Insurance system. In a BPH cohort, we identified 1,489 patients with cancer and included them in our study group. For the control group, 3 patients without cancer were frequency matched with each BPH case for age, BPH diagnosis year, index year, and month. Information regarding past 5ARI use was obtained from the Taiwanese National Health Insurance Research Database (NHIRD). Multivariate logistic regression analysis was conducted, and odds ratio (OR) and 95% confidence interval (CI) were estimated.

RESULTS

Finasteride use marginally increased the incidence of prostate and overall cancer at a level of statistical significance (prostate cancer: OR = 1.90; 95% CI: 1.00-3.59; overall cancer: OR = 1.51; 95% CI: 1.00-2.28). Dutasteride use significantly increased kidney cancer risk (OR = 9.68, 95% CI: 1.17-80.0). Dosage analysis showed that lower doses of finasteride were associated with higher overall and prostate cancer risks. The major limitation is the lack of important data in the NHIRD, such as prostate cancer histologic grades, smoking habits, alcohol consumption, body mass index, socioeconomic status, and family history of cancer.

CONCLUSIONS

This population-based nested case-control study suggested that finasteride use may increase prostate and overall cancer risks for patients with BPH. The effects were more prominent for patients using lower doses of finasteride.

Dutasteride for the treatment of prostate-related conditions

INTRODUCTION

A variety of pharmaceuticals have been developed directed at mitigating the symptoms associated with benign prostatic hypertrophy (BPH) and have also been evaluated for their potential role in prevention and treatment of prostate cancer. One such agent is dutasteride , a non-selective inhibitor of 5α-reductase, an enzyme responsible for conversion of testosterone to a more potent androgen dihydrotestosterone (DHT).

AREAS COVERED

This review will cover the safety profile of dutasteride when it is used in the treatment of prostate-related conditions, specifically looking at the pivotal clinical trials on this drug.

EXPERT OPINION

Dutasteride has proved to be a safe and efficacious treatment for symptoms related to BPH. The primary safety concern relates to the increased incidence of high-grade prostate cancer seen in men treated with dutasteride in the setting of prostate cancer prevention. Dutasteride has a role as an adjunct in the treatment of prostate cancer; however, this is an area still under active investigation. It is not recommended for use in prostate cancer prevention given the increased risk of high-grade cancers.

The case for prostate cancer risk reduction by 5-alpha reductase inhibitors

Prostate cancer remains a significant public health problem. The current approach with prostate-specific antigen (PSA)-based screening has questionable effects on prostate cancer-specific mortality but is clearly associated with overdiagnosis of prostate cancer, especially relatively low-risk and low-volume tumors. Methods to decrease overdiagnosis include alterations in screening practices and, potentially, the use of 5-alpha reductase inhibitors. This article reviews the major trials that have evaluated 5-alpha reductase inhibitors in this setting: the Prostate Cancer Prevention Trial (PCPT) and the Reduction by Dutasteride Prostate Cancer Events Trial (REDUCE). Although these trials enrolled different patient populations, their findings are complementary and suggest a potential role for these agents in prostate cancer risk reduction. Use of 5-alpha reductase inhibitors results in an approximate 25% reduction in the detection of prostate cancer, reduces diagnosis of high-grade prostatic intraepithelial neoplasia (PIN), and improves benign prostatic hyperplasia (BPH)-related outcomes and the performance of PSA as a diagnostic test for aggressive prostate cancer. Side effects occur in a small percentage of men and consist of decreased sexual function and libido as well as gynecomastia. The risk of high-grade tumor development while receiving these agents is uncertain.

Bloodless management of benign prostatic hyperplasia: medical and minimally invasive treatment options

Benign prostatic hyperplasia (BPH) is a medical condition affecting a wide range of the aging male population resulting in various degrees of lower urinary tract symptoms (LUTS). Today, a variety of medical therapies and minimally invasive BPH treatment modalities are available. Medical therapy includes α(1) blockers, 5()α reductase inhibitors and combination therapy. When these options fail, surgery is indicated. Transurethral resection of the prostate (TURP) is still considered the gold standard surgical treatment for BPH. Nevertheless, numerous minimally invasive treatment alternatives are available that are comparable in effectiveness to TURP, with significantly less morbidity. In this article, current treatment options for BPH are reviewed with respect to their indications, long-term safety and efficacy in relieving BPH related LUTS. The selection of the type of BPH treatment should be based on the physician's experience, patient's co-morbidities as well as the prostate size and clinical disease progression.

Reduced levels of 5-α reductase 2 in adult prostate tissue and implications for BPH therapy

BACKGROUND

5-α reductase 2 (5-AR 2) is a key enzyme that is responsible of proper development of prostate tissue. Inhibition of 5-AR 2 has proven to be efficacious for management of urinary symptoms secondary benign prostatic hyperplasia (BPH). However, some patients are resistant to the therapeutic effects of 5-AR 2 inhibitor. We wished to determine why some benign non-cancerous adult human prostates do not express 5-AR 2, and hypothesized that methylation of 5-AR 2 promoter region correlated with low expression of 5-AR 2 protein.

METHODS

The transition zone of 42 human prostate tissues after radical prostatectomy was used for evaluation. Initially, 21 paraffin embedded samples were used to assess immunoreactivity to 5-AR 2 antibody in non-cancerous BPH samples. In the next 21 samples, fresh frozen prostate transition zone samples without cancer were assessed for immunoreactivity and methylation of the 5-AR 2 promoter using methyl-specific PCR.

RESULTS

We show that 6/21 (29%) of benign human prostate samples did not express the 5-AR 2 protein. Moreover, the promoter region of 5-AR 2 contains a CpG island that is methylated in benign prostate epithelial cells in culture and also in 39% (7/18) human prostate tissues. We show a strong correlation between methylation of the 5-AR 2 promoter region and absence of 5-AR 2 protein expression (P = 0.0025, Fisher's exact test).

CONCLUSIONS

Methylation of 5-AR 2 promoter may account for low or absent expression of 5-AR 2 in some human adult prostate tissues.

The role of 5-alpha reductase inhibitors in prostate pathophysiology: Is there an additional advantage to inhibition of type 1 isoenzyme?

Normal growth and function of the prostate are contingent on the reduction of testosterone to dihydrotestosterone (DHT) by 5-alpha reductase (5-AR) enzymes types 1 and 2. It has been theorized that an overabundance of DHT may be implicated in the pathogenesis of both benign prostatic hyperplasia (BPH) and prostate cancer. Inhibitors of 5-AR such as dutasteride and finasteride may therefore have an important role in the prevention and treatment of BPH and prostate cancer. Dutasteride provides greater suppression of DHT than finasteride, thereby underlying the hypothesis that inhibition of both type 1 and type 2 would provide correspondingly greater protection than inhibition of type 2 alone. We review the potential significance of the 5-AR inhibitors in reducing the risk of prostate cancer according to the basic biology of prostate disease.

Usefulness of prostate-specific antigen (PSA) rise as a marker of prostate cancer in men treated with dutasteride: lessons from the REDUCE study

OBJECTIVES

To determine if dutasteride-treated men can be monitored safely and adequately for prostate cancer based on data from the Reduction by Dutasteride in Prostate Cancer Events (REDUCE) study. To analyse whether the use of treatment-specific criteria for repeat biopsy maintains the usefulness of prostate-specific antigen (PSA) level for detecting high grade cancers.

PATIENTS AND METHODS

The REDUCE study was a randomized, double-blind, placebo-controlled investigation of whether dutasteride (0.5 mg/day) reduced the risk of biopsy-detectable prostate cancer in men with a previous negative biopsy. The usefulness of PSA was evaluated using biopsy thresholds defined by National Comprehensive Cancer Network guidelines in the placebo group and any rise in PSA from nadir (the lowest PSA level achieved while in the study) in the dutasteride group. The number of cancers detected on biopsy in the absence of increased/suspicious PSA level as well as sensitivity, specificity, positive predictive value and negative predictive value for high grade prostate cancer detection were analysed by treatment group. Prostate cancer pathological characteristics were compared between men who did and did not meet biopsy thresholds.

RESULTS

Of 8231 men randomized, 3305 (dutasteride) and 3424 (placebo) underwent at least one prostate biopsy during the study and were included in the analysis. If only men meeting biopsy thresholds underwent biopsy, 25% (47/191) of Gleason 7 and 24% (7/29) of Gleason 8-10 cancers would have been missed in the dutasteride group, and 37% (78/209) of Gleason 7 and 22% (4/18) Gleason 8-10 cancers would have been missed in the placebo group. In both groups, the incidence of Gleason 7 and Gleason 8-10 cancers generally increased with greater rises in PSA. Sensitivity of PSA kinetics was higher and specificity was lower for the detection of Gleason 7-10 cancers in men treated with dutasteride vs placebo. Men with Gleason 7 and Gleason 8-10 cancer meeting biopsy thresholds had greater numbers of positive cores, percent core involvement, and biopsy cancer volume vs men not meeting thresholds.

CONCLUSION

Using treatment-specific biopsy thresholds, the present study shows that the ability of PSA kinetics to detect high grade prostate cancer is maintained with dutasteride compared with placebo in men with a previous negative biopsy. The sensitivity of PSA kinetics with dutasteride was similar to (Gleason 8-10) or higher than (Gleason 7-10) the placebo group; however, biopsy decisions based on a single increased PSA measurement from nadir in the dutasteride group resulted in a lower specificity compared with using a comparable biopsy threshold in the placebo group, indicating the importance of confirmation of PSA measurements.

Chemoprevention of prostate cancer

Over the past two decades, many more men are diagnosed with prostate cancer then die of the disease. This increase in diagnosis has led to aggressive treatment of indolent disease in many individuals and has been the impetus for finding a means of reducing the risk of prostate cancer. In the past decade, there have been eight large trials of prostate cancer risk reduction using dietary supplements, 5α-reductase inhibitors, or anti-estrogens. The only two trials which have demonstrated efficacy are those involving 5α-reductase inhibitors: the PCPT (finasteride) and REDUCE (dutasteride). This review examines prostate cancer risk reduction, with emphasis on conclusions that can be drawn from these two landmark studies.

5-α-Reductase inhibitors for prostate cancer chemoprevention: an updated Cochrane systematic review

OBJECTIVE

• To estimate the benefits and harms of 5-α-reductase inhibitors (5-α-RIs) in preventing prostate cancer.

MATERIALS AND METHODS

• We searched MEDLINE and the Cochrane Collaboration Library through June 2010 to identify randomized trials. • We included articles if they examined 5-α-RI vs control, were ≥ 1 year in duration and provided clinical outcomes. • Our primary outcome was prostate cancer period-prevalence 'for-cause'.

RESULTS

• Eight studies met inclusion criteria but only the Prostate Cancer Prevention Trial and the Reduction by Dutasteride of Prostate Cancer Events were designed to assess the impact of 5-α-RIs on prostate cancer period-prevalence. The mean age of enrolees was 64 years, 92% were White, and mean PSA level was 3.1 ng/mL. For-cause prostate cancers comprised 54% of all cancers detected in placebo-controlled studies. • Compared with placebo, 5-α-RI resulted in a 25% relative risk (RR) reduction in prostate cancers detected for-cause [RR 0.75, 95% confidence interval (CI) 0.67-0.83; 1.4% absolute risk reduction (3.5% vs 4.9%)]. One BPH trial reported that the risk of prostate cancers detected for-cause was significantly reduced with dutasteride and combined dutasteride plus tamsulosin compared with tamsulosin monotherapy. • Six trials vs placebo assessed prostate cancers detected overall. There was a 26% RR reduction favouring 5-α-RI [RR 0.74, 95% CI 0.55-1.00; 2.9% absolute risk reduction (6.3% vs 9.2%)]. There were reductions across categories of age, race and family history of prostate cancer. • One placebo-controlled trial of men that investigators considered at greater risk for prostate cancer (based on age, elevated PSA level and having a previous suspicion of prostate cancer leading to a prostate biopsy) reported that dutasteride did not reduce prostate cancers detected for-cause based on needle-biopsy but did reduce risk of overall incident prostate cancer detected by biopsy by 23%[RR 0.77, 95% CI 0.70-0.85; absolute reduction 16.1% vs 20.8%]. There were reductions across age, family history of prostate cancer, PSA level, and prostate volume subgroups. • Incidences of erectile dysfunction, ejaculate volume, decreased libido, and gynaecomastia were greater with 5-α-RI vs placebo.

CONCLUSIONS

• 5-α-RIs reduce the risk of being diagnosed with prostate cancer among men who are screened regularly for prostate cancer. • Information is inadequate to assess the effect of 5-α-RIs on prostate cancer or all-cause mortality. • 5-α-RIs increase sexual and erectile dysfunction.

Are men on 5α-reductase inhibitors appropriately referred to urology? A survey of primary care physicians

OBJECTIVE

• To investigate among general practitioners (GPs) their level of awareness and indications for urological consultations in patients treated with 5α-reductase inhibitors (5ARIs).

SUBJECTS AND METHODS

• We conducted a survey of GPs in Quebec. • Questions covered GPs' preferred benign prostatic hyperplasia (BPH) management, knowledge of 5ARIs, their role in prostate cancer prevention, and triggers for urology consultation.

RESULTS

• Of the surveys mailed, 599 were returned (15.7% response rate). • Therapy with 5ARIs was initiated by GPs in 34.3%, with 20% and 12% preferring 5ARIs alone and combined with an α-blocker as first-line therapy for BPH, respectively. • Once on therapy, 74% did not refer to a urologist if the PSA level did not decline after 6-12 months. • Finally, 40.7% would not advocate 5ARI chemoprevention for prostate cancer, regardless of risk reduction. • Findings were not associated with GP gender, experience or geographic location of practice (urban versus rural).

CONCLUSIONS

• There was a preference amongst GP to use α-blockers over 5ARIs for BPH and hesitancy to use them in prostate cancer chemoprevention. • There is a lack of awareness of 5ARI effects on PSA kinetics and a reluctance to refer to a urologist. • Further education in Quebec is needed about 5ARIs to optimize their usage and avoid delaying cancer detection.

The different reduction rate of prostate-specific antigen in dutasteride and finasteride

Purpose

To compare and analyze the therapeutic effects and changes in the prostate-specific antigen (PSA) level with treatment with finasteride or dutasteride for benign prostatic hyperplasia (BPH) for 1 year.

Materials and Methods

We retrospectively investigated patients who suffered from BPH for 1 year between January 2005 and December 2008. For treatment groups, we divided the patients into two groups: one was treated with alfuzosin and finasteride and the other was treated with alfuzosin and dutasteride. At the beginning of treatment, the patients underwent transrectal ultrasonography and measurement of urine flow rate, residual urine volume, PSA, and International Prostate Symptom Score (IPSS). Patients with diseases affecting urinary function were excluded. We not only analyzed the data at the time of initial treatment, but also after 1 year of treatment. A total of 219 patients were able to be evaluated for 1 year.

Results

Both finasteride and dutasteride reduced PSA and prostate volume significantly. The comparison between groups showed a more significant reduction of PSA (p=0.020) and prostate volume (p=0.052) in the dutasteride group. Other parameters did not differ significantly between the groups.

Conclusions

5-α Reductase inhibitors for BPH treatment reduced PSA and prostate volume significantly when the patients were treated for 1 year. Administration of dutasteride is considered to be more effective in reducing PSA and prostate volume. Therefore, dutasteride should not be considered equivalent to finasteride in the reduction rate of PSA. The intensity of dutasteride must be reevaluated in comparison with finasteride.

Finasteride for benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH), a non-malignant enlargement of the prostate in aging men, can cause bothersome urinary symptoms (intermittency, weak stream, straining, urgency, frequency, incomplete emptying). Finasteride, a five-alpha reductase inhibitor (5ARI), blocks the conversion of testosterone to dihydrotestosterone, reduces prostate size, and is commonly used to treat symptoms associated with BPH.

OBJECTIVES

To compare the clinical effectiveness and harms of finasteride versus placebo and active controls in the treatment of lower urinary tract symptoms (LUTS).

SEARCH STRATEGY

We searched The Cochrane Library (which includes CDSR (Cochrane Database of Systematic Reviews), DARE (Database of Abstracts of Reviews of Effects), HTA (Heath Technology Assessments), and CENTRAL (Cochrane Central Register of Controlled Trials, and which includes EMBASE and MEDLINE), LILACS (Latin American and Caribbean Center on Health Sciences Information) and Google Scholar for randomized, controlled trials (RCTs). We also handsearched systematic reviews, references, and clinical-practice guidelines.

SELECTION CRITERIA

Randomized trials in the English language with placebo and/or active arms with a duration of at least 6 months.

DATA COLLECTION AND ANALYSIS

JT extracted the data, which included patient characteristics, outcomes, and harms. Our primary outcome was change in a validated, urinary symptom-scale score, such as the AUA/IPSS. A clinically meaningful change was defined as 4 points. We also categorized outcomes by trial lengths of ≤ 1 year (short term) and > 1 year (long term).

MAIN RESULTS

Finasteride consistently improved urinary symptom scores more than placebo in trials of > 1 year duration, and significantly lowered the risk of BPH progression (acute urinary retention, risk of surgical intervention, ≥ 4 point increase in the AUASI/IPSS). In comparison to alpha-blocker monotherapy, finasteride was less effective than either doxazosin or terazosin, but equally effective compared to tamsulosin. Both doxazosin and terazosin were significantly more likely than finasteride to improve peak urine flow and nocturia, versus finasteride. Versus tamsulosin, peak urine flow and QoL improved equally well versus finasteride. However, finasteride was associated with a lower risk of surgical intervention compared to doxazosin, but not to terazosin, while finasteride and doxazosin were no different for risk of acute urinary retention. Two small trials reported no difference in urinary symptom scores between finasteride and tamsulosin. Finasteride + doxazosin and doxazosin monotherapy improved urinary symptoms equally well (≥ 4 point improvement).For finasteride, there was an increased risk of ejaculation disorder, impotence, and lowered libido, versus placebo. Versus doxazosin, finasteride had a lower risk of asthenia, dizziness, and postural hypotension, and versus terazosin, finasteride had a significant, lower risk of asthenia, dizziness, and postural hypotension.

AUTHORS' CONCLUSIONS

Finasteride improves long-term urinary symptoms versus placebo, but is less effective than doxazosin. Long-term combination therapy with alpha blockers (doxazosin, terazosin) improves symptoms significantly better than finasteride monotherapy. Finasteride + doxazosin improves symptoms equally - and clinically - to doxazosin alone. In comparison to doxazosin, finasteride + doxazosin appears to improve urinary symptoms only in men with medium (25 to < 40 mL) or large prostates (≥ 40 mL), but not in men with small prostates (25 mL).Comparing short to long-term therapy, finasteride does not improve symptoms significantly better than placebo at the short term, but in the long term it does, although the magnitude of differences was very small (from < 1.0 point to 2.2 points). Doxazosin improves symptoms better than finasteride both short and long term, with the magnitude of differences ∼2.0 points and 1.0 point, respectively. Finasteride + doxazosin improves scores versus finasteride alone at both short and long term, with mean differences ∼2.0 points for both time points. Finasteride + doxazosin versus doxazosin improves scores equally for short and long term.Drug-related adverse effects for finasteride are rare; nevertheless, men taking finasteride are at increased risk for impotence, erectile dysfunction, decreased libido, and ejaculation disorder, versus placebo. Versus doxazosin, which has higher rates of dizziness, postural hypotension, and asthenia, men taking finasteride are at increased risk for impotence, erectile dysfunction, decreased libido, and ejaculation disorder. Finasteride significantly reduces asthenia, postural hypotension, and dizziness versus terazosin. Finasteride significantly lowers the risk of asthenia, dizziness, ejaculation disorder, and postural hypotension, versus finasteride + terazosin.