5α-Reductase inhibitors and risk of high-grade or lethal prostate cancer

Five-alpha reductase inhibitors and risk of prostate cancer among men with benign prostatic hyperplasia: A historical cohort study using primary care data

Background: Five-alpha reductase inhibitors (5ARIs) are used in the management of benign prostatic hyperplasia (BPH). 5ARIs prevent the conversion of testosterone to dihydrotestosterone, which is important in prostate development. It has been suggested that 5ARIs can be used a chemopreventative agent for prostate cancer. The aim of this study was to assess the risk of prostate cancer associated with 5ARI use among men with BPH. Methods: Using Clinical Practice Research Datalink (CPRD) from 1992 to 2011 in UK, prostate cancer risk was retrospectively compared in men with a new diagnosis of BPH, with no history of prostate cancer who were treated with 5ARIs, to men treated with alpha blockers (ABs) and those given no pharmacological treatment. Incidence rate of prostate cancer was calculated by treatment group; the association between BPH treatment group and prostate cancer was estimated by a multivariate Cox model. Results: 77,494 men with newly diagnosed BPH were included. The crude incidence rate of prostate cancer was 892.4 cases per 100,000 person-years amongst those treated with 5ARIs, compared with 1209.0 and 1542.9 in those treated with ABs and untreated individuals, respectively. The HR adjusted for potential confounders was 0.79 (0.72-0.86) for 5ARI vs ABs and 0.72 (0.66-0.79) for 5ARI vs untreated. After excluding the first year after BPH diagnosis, adjusted HRs attenuated to 0.87 (0.79-0.97) for 5ARI vs ABs and 0.97 (0.87-1.08) for 5ARI vs untreated. Conclusion: Among men diagnosed with BPH, we found evidence of lower risks of subsequent prostate cancer in those treated with 5ARIs, but this appeared to be driven by cases diagnosed within a year of BPH, possibly reflecting prevalent prostate cancers that were initially misdiagnosed. After excluding the first year after BPH diagnosis, there was little evidence of a reduced prostate cancer risk in those taking 5ARIs.

Statins and Cancer Prevention-Association Does Not Mean Causation

Statins are widely prescribed medications that inhibit 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG CoA) reductase and therefore reduce cholesterol synthesis. Given the key role of cholesterol in cancer, statins may therefore have anticancer activities. However, clinical studies investigating the association between statin usage and cancer development have been few and inconsistent. A recent study from Maeda-Minami and colleagues found a significant, though modest, decrease in cancer risk among statin users. However, does this finding mean statin usage directly reduces cancer risk or is merely associated with reduced cancer risk? This editorial analyzes Maeda-Minami and colleagues' study to provide commentary on statin's proposed role in preventing cancer. See related article, p. 37.

Prostate cancer specific mortality after 5α-reductase inhibitors medication in benign prostatic hyperplasia patients: systematic review and meta-analysis

BACKGROUND

Our study was conducted to investigate the effect of 5-ARI on the death rate from prostate cancer by means of an updated meta-analysis using related data.

METHODS

We did comprehensive literature searches using the PubMed, Embase, and Cochrane databases through July 2019. We evaluated the risk of bias in such studies using the ROBINS-I tool and analyzed deaths from cancer and deaths from all causes using HR.

RESULTS

The meta-analysis included 11 studies. The pooled overall HRs for cancer-specific deaths between 5-ARI treatment versus non-exposed groups were 0.937 (95% CI: 0.730, 1.201). In the subgroup moderator analysis, the number of patients and additional medication variables were significantly associated with deaths from all causes (p = 0.022 and p = 0.005, respectively). For detecting the publication bias or small-study effect in the included studies, we performed Begg and Mazumdar's correlation test (0.851 and 0.573) and Egger's regression coefficient test (0.035 and 0.245) and ​suggested that there was no evidence of publication bias or small-study effect in this meta-analysis.

CONCLUSIONS

Our study indicated that exposure to 5-ARI had no close association between the overall death rate or cancer-specific deaths. To confirm these results, well-designed prospective studies with large samples are required.

Urban-Rural Differences in Clinical Characteristics of Prostate Cancer at Initial Diagnosis: A Single-Center Observational Study in Anhui Province, China

Background

People residing in rural areas have higher prostate cancer (PCa) mortality to incidence ratio (M/I) and worse prognosis than those in urban areas of China. Clinical characteristics at initial diagnosis are significantly associated with biochemical recurrence, overall survival, and PCa disease-free survival.

Objective

This study aimed at investigating the clinical characteristics at initial diagnosis of urban and rural PCa patients and to establish a logistic regression model for identifying independent predictors for high-grade PCa.

Materials and Methods

Clinical characteristics for PCa patients were collected from the largest prostate biopsy center in Anhui province, China, from December 2015 to March 2019. First, urban-rural disparities in clinical characteristics were evaluated at initial diagnosis. Second, based on pathological findings, we classified all participants into the benign+ low/intermediate-grade PCa or high-grade PCa groups. Univariate and multivariate logistic regression analyses were performed to identify independent factors for predicting high-grade PCa, while a nomogram for predicting high-grade PCa was generated based on all independent factors. The model was evaluated using area under receiver-operating characteristic (ROC) curve as well as calibration curve analyses and compared to a model without the place of residence factor of individuals.

Results

Statistically significant differences were observed between urban and rural PCa patients with regard to tPSA, PSA density (PSAD), and Gleason score (GS) (p < 0.05). Logistic regression analysis revealed that tPSA [OR = 1.060, 95% confidence interval (CI): 1.024, 1.098], PSAD (OR = 14.678, 95%CI: 4.137, 52.071), place of residence of individuals (OR = 5.900, 95%CI: 1.068, 32.601), and prostate imaging reporting and data system version 2 (PI-RADS v2) (OR = 4.360, 95%CI: 1.953, 9.733) were independent predictive factors for high-grade PCa. The area under the curve (AUC) of the nomogram was greater than that of the model without the place of residence of individuals. The calibration curve of the nomogram indicated that the prediction curve was basically fitted to the standard curve, suggesting that the prediction model had a better calibration ability.

Conclusions

Compared to urban PCa patients, rural PCa patients presented elevated tPSA, PSAD levels, and higher pathological grades. The place of residence of the individuals was an independent predictor for high-grade PCa in Anhui Province, China. Therefore, appropriate strategies, such as narrowing urban-rural gaps in access to health care and increasing awareness on the importance of early detection should be implemented to reduce PCa mortality rates.

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 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.

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.

Long-term use of 5-alpha-reductase inhibitors is safe and effective in men on active surveillance for prostate cancer

BACKGROUND

Although 5-alpha-reductase inhibitors (5ARIs) have been shown to benefit men with prostate cancer (PCa) on active surveillance (AS), their long-term safety remains controversial. Our objective is to describe the long-term association of 5ARI use with PCa progression in men on AS.

MATERIALS/SUBJECTS AND METHODS

The cohort of men with low-risk PCa was derived from a prospectively maintained AS database at the Princess Margaret (1995-2016). Pathologic, grade, and volume progression were the primary end points. Kaplan-Meier time-to-event analysis was performed and Cox proportional hazards regression was used to determine predictors of progression where 5ARI exposure was analyzed as a time-dependent variable. Patients who came off AS prior to any progression events were censored at that time.

RESULTS

The cohort included 288 men with median follow-up of 82 months (interquartile range: 37-120 months). Among non-5ARI users (n = 203); 114 men (56.2%) experienced pathologic progression compared with 24 men (28.2%) in the 5ARI group (n = 85), (p < 0.001). Grade and volume progression were higher in the non-5ARI group compared with the 5ARI group (n = 82; 40.4% vs. n = 19; 22.4% respectively, p = 0.003 for grade progression; n = 87; 43.1% and n = 15; 17.7%, respectively for volume progression p < 0.001). Lack of 5ARI use was independently positively associated with pathologic progression (HR: 2.65; CI: 1.65-4.24), grade progression (HR: 2.75; CI: 1.49-5.06), and volume progression (HR: 3.15; CI: 1.78-5.56). The frequency of progression to high-grade (Grade Group 4-5) tumors was not significantly different between the groups.

CONCLUSIONS

Use of 5ARIs diminished both grade and volume progression without an increased risk of developing Grade Groups 4-5 disease.

Post-finasteride syndrome - does it really exist?

Inhibitors of 5α-steroid reductase are drugs used to treat androgen-dependent conditions including prostate diseases and androgenic alopecia. Finasteride was the first on the market and is currently the most widely used inhibitor. Dutasteride was the second inhibitor to be approved and has a similar safety profile. Common adverse events of treatment consist of sexual disorders and a negative affect balance. It was described that the prolonged use of 5α-steroid reductase inhibitors in patients with alopecia can cause persistent side effects called a post-finasteride syndrome (PFS), that is not just a simple coexistence of events, but rather a definite syndrome with an iatrogenic background. PFS occurs in susceptible individuals even after small doses of the drug and can last for a long time after the discontinuation of treatment. A deterioration in the quality of life in affected individuals does not justify use of the drug. Wider recognition of PFS symptoms, its incidence, course, prevention, and treatment possibilities will allow the indications for drug use to be reconsidered and treatment to be more personalized. Knowledge about PFS will also help to provide the best treatment for affected individuals and to properly educate patients before obtaining an informed consent for therapy with 5α-steroid reductase inhibitors.

Association between 5α-reductase inhibitors therapy and incidence, cancer-specific mortality, and progression of prostate cancer: evidence from a meta-analysis

5α-reductase inhibitors (5-ARI) are widely employed for the treatment of benign prostatic hyperplasia. It has been noted that 5-ARI exhibit the potential to attenuate the risk of prostate cancer, but consistent agreement has not been achieved. Moreover, the effect of 5-ARI on cancer-specific mortality and progression of prostate cancer remains unclear. Therefore, the goal of the current meta-analysis was to elucidate the impact of 5-ARI on the incidence and progression of prostate cancer. We searched for all studies assessing the effect of 5-ARI on risk of prostate cancer in PubMed, Embase, Medline, and Cochrane Library databases. Pooled relative risk (RR) and corresponding 95% confidence intervals (CIs) were accepted to evaluate the association between 5-ARI and the risk of prostate cancer. Synthetic results implied that subjects who accepted 5-ARI compared with the placebo group experienced a distinctly weakened overall incidence of prostate cancer (RR = 0.74; 95% CI: 0.66–0.82; P < 0.001). Subgroup analyses further revealed that 5-ARI reduction of the incidence of prostate cancer was limited to low-grade (Gleason score 2–6; RR = 0.68; 95% CI: 0.57–0.81; P < 0.001) and intermediate-grade tumors (Gleason score 7; RR = 0.81; 95% CI: 0.67–0.97; P = 0.023), but not high-grade tumors (Gleason score >7; RR = 1.19; 95% CI: 0.98–1.43; P = 0.069). The results also showed that 5-ARI treatment did not significantly alter prostate cancer-specific mortality (RR = 1.0; 95% CI: 0.95–1.05; P = 0.916). In addition, it was worth noting that 5-ARI treatment acted in a protective role that presented a dramatic benefit to delay the progression of low-risk tumors (RR = 0.58; 95% CI: 0.43–0.78; P < 0.001).

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.

The Use of 5-Alpha Reductase Inhibitors to Manage Benign Prostatic Hyperplasia and the Risk of All-cause Mortality

OBJECTIVE

To compare the risk of mortality among men treated for benign prostatic hyperplasia (BPH) with 5 alpha-reductase inhibitors (5ARI) to those treated with alpha-blockers (AB) in community practice settings.

METHODS

We employed a retrospective matched cohort study in 4 regions of an integrated healthcare system. Men aged 50 years and older who initiated pharmaceutical treatment for BPH and/or lower urinary tract symptoms between 1992 and 2008 and had at least 3 consecutive prescriptions that were eligible and followed through 2010 (N = 174,895). Adjusted hazard ratios were used to estimate the risk of mortality due to all-causes associated with 5ARI use (with or without concomitant ABs) as compared to AB use.

RESULTS

In this large and diverse sample with 543,523 person-years of follow-up, 35,266 men died during the study period, 18.9% of the 5ARI users and 20.4% of the AB users. After adjustment for age, medication initiation year, race, region, prior AB history, Charlson score, and comorbidities, 5ARI use was not associated with an increased risk of mortality when compared to AB use (Adjusted hazard ratios: 0.64, 95% confidence interval: 0.62, 0.66).

CONCLUSION

Among men receiving medications for BPH in community practice settings, 5ARI use was not associated with an increased risk of mortality when compared to AB use. These data provide reassurance about the safety of using 5ARIs in general practice to manage BPH and/or lower urinary tract symptoms.

Impact of Metabolic Diseases, Drugs, and Dietary Factors on Prostate Cancer Risk, Recurrence, and Survival: A Systematic Review by the European Association of Urology Section of Oncological Urology

CONTEXT

To date, established risk factors for prostate cancer (PCa) are limited to age, race, family history, and certain genetic polymorphisms. Despite great research efforts, available evidence on potentially modifiable risk factors is conflicting. Moreover, most studies on PCa risk factors did not consider the impact of prostate-specific antigen (PSA) testing on PCa diagnosis.

OBJECTIVE

To provide a detailed overview of the latest evidence on the role of metabolic diseases, drugs, and dietary factors for risk of PCa incidence, recurrence, and survival in men exposed to PSA testing.

EVIDENCE ACQUISITION

A systematic review of the English-language literature was performed using the MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science databases according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses recommendations. Randomized, case-control, or cohort studies published during the periods 2008-2017 (on drugs and metabolic diseases) and 2003-2017 (on dietary factors), with extensive follow-up (≥8-10yr for studies on PCa risk; ≥2-5yr for studies on PCa recurrence, progression, and survival, depending on the review subtopic) and adjusting of the analyses, beyond established risk factors, for either rate of PSA testing (for risk analyses) or PCa stage and primary treatment (for survival analyses), were eligible for inclusion.

EVIDENCE SYNTHESIS

Overall, 39 reports from 22 observational studies were included. Studies were heterogeneous regarding definitions of exposure or outcomes, length of follow-up, risk of bias, and confounding. For some risk factors, evidence was insufficient to assess potential effects, while for others there was no evidence of an effect. For selected risk factors, namely metformin, aspirin and statin use, diabetes, obesity, and specific dietary intakes, there was low-quality evidence of modest effects on PCa risk.

CONCLUSIONS

Current evidence from long-term observational studies evaluating the effect of drugs, metabolic diseases, and dietary factors for PCa risk considering the impact of PSA testing is still not conclusive. Future research is needed to confirm the associations suggested by our review, exploring their potential biological explanations and selecting those risk factors most likely to trigger effective public health interventions.

PATIENT SUMMARY

We reviewed the available studies published in the recent literature on the potential role of drugs, metabolic diseases, and food and dietary factors for the risk of prostate cancer, considering the impact of prostate-specific antigen testing on prostate cancer diagnosis. We found that for some factors data are currently insufficient to make definitive conclusions, while for others available studies seem to indicate an effect on the risk of prostate cancer.

Risk stratification for benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) represents an important public health problem in ageing men due to frequently associated lower urinary tract symptoms (LUTS), which may impair quality of life. BPH is also a progressive disease, mainly characterized by a worsening of LUTS over time, and in some patients by the occurrence of serious outcomes such as acute urinary retention and need for BPH-related surgery. The management of BPH and LUTS in men should move forward its focus on symptom control only. Indeed, the goals of therapy for BPH are not only to improve bothersome LUTS but also to identify those patients at risk of unfavourable outcomes in order to optimize their management and reduce complications. Risk stratification and tailored treatment should improve the reductions in both symptoms and the long-term consequences of BPH and BPH treatments. To do this, clinicians need to know possible factors that may support the develop of PBH and possible risks due to the BPH itself.

5-Alpha Reductase Inhibitors and the Risk of Prostate Cancer Mortality in Men Treated for Benign Prostatic Hyperplasia

OBJECTIVE

To compare the risk of prostate cancer mortality among men treated with 5- alpha reductase inhibitors (5-ARIs) with those treated with alpha-adrenergic blockers (ABs) in community practice settings.

PATIENTS AND METHODS

A retrospective matched cohort (N=174,895) and nested case-control study (N=18,311) were conducted in 4 regions of an integrated health care system. Men 50 years and older who initiated pharmaceutical treatment for benign prostatic hyperplasia between January 1, 1992, and December 31, 2007, and had at least 3 consecutive prescriptions were followed through December 31, 2010. Adjusted subdistribution hazard ratios, accounting for competing risks of death, and matched odds ratios were used to estimate prostate cancer mortality associated with 5-ARI use (with or without concomitant ABs) as compared with AB use.

RESULTS

In the cohort study, 1,053 men died of prostate cancer (mean follow-up, 3 years), 15% among 5-ARI users (N= 25,388) and 85% among AB users (N=149,507) (unadjusted mortality rate ratio, 0.80). After accounting for competing risks, it was found that 5-ARI use was not associated with prostate cancer mortality when compared with AB use (adjusted subdistribution hazard ratio, 0.85; 95% CI, 0.72-1.01). Similar results were observed in the case-control study (adjusted matched odds ratio, 0.95; 95% CI, 0.78-1.17).

CONCLUSION

Among men being pharmaceutically treated for benign prostatic hyperplasia, 5-ARI use was not associated with an increased risk of prostate cancer-specific mortality when compared with AB use. The increased prevalence of high-grade lesions at the time of diagnosis noted in our study and the chemoprevention trials may not result in increased prostate cancer mortality.

Warfarin use and prostate cancer risk in the Finnish Randomized Study of Screening for Prostate Cancer

OBJECTIVE

Anticoagulants, especially vitamin K antagonists (VKAs) such as warfarin, have been hypothesized to have antitumor properties, and use of VKAs has been associated with a lower prostate cancer (PCa) risk. This study estimated PCa risk among users of warfarin and other anticoagulants.

MATERIALS AND METHODS

All anticoagulant use among 78,615 men during 1995-2009 was analyzed. Cox regression, adjusted for age, screening trial arm and use of other medications, with medication use as a time-dependent variable, was used to estimate PCa risk overall, and by tumor grade and stage.

RESULTS

In total, 6537 men were diagnosed with PCa during 1995-2009 (1210 among warfarin users). Compared to non-users, warfarin use was associated with an increased risk of PCa [multivariable-adjusted hazard ratio (HR) = 1.11, 95% confidence interval (CI) 1.01-1.22]. This was limited to short-term, low-dose use, and was not observed in long-term use. A similar overall risk increase was observed for Gleason grade 7-10 PCa. Low-dose, short-term use of warfarin was associated with an increased risk of metastatic PCa. However, the increase in risk vanished with continued use. Compared to other anticoagulants, low-dose use of warfarin was associated with a slightly elevated overall PCa risk (HR = 1.19, 95% CI 1.00-1.43). The increase in risk disappeared in long-term, high-dose use.

CONCLUSIONS

This study, which included a larger number of PCa cases with warfarin exposure than previous studies, does not support previous notions of decreased risk of PCa among warfarin users. A similar risk of PCa was found among warfarin users and the general population, and no difference in risk was found between warfarin and other anticoagulants.

Adverse Effects and Safety of 5-alpha Reductase Inhibitors (Finasteride, Dutasteride): A Systematic Review

Finasteride and dutasteride, both 5-alpha reductase inhibitors, are considered first-line treatment for androgenetic hair loss in men and used increasingly in women. In each case, patients are expected to take the medications indefinitely despite the lack of research regarding long-term adverse effects. Concerns regarding the adverse effects of these medications has led the United States National Institutes of Health to add a link for post-finasteride syndrome to its Genetic and Rare Disease Information Center. Herein, the authors report the results of a literature search reviewing adverse events of 5-alpha reductase inhibitors as they relate to prostate cancer, psychological effects, sexual health, and use in women. Several large studies found no increase in incidence of prostate cancer, a possible increase of high-grade cancer when detected, and no change in survival rate with 5-alpha reductase inhibitor use. Currently, there is no direct link between 5-alpha reductase inhibitor use and depression; however, several small studies have led to depression being listed as a side effect on the medication packaging. Sexual effects including erectile dysfunction and decreased libido and ejaculate were reported in as many as 3.4 to 15.8 percent of men. To date, there are very few studies evaluating 5-alpha reductase inhibitor use in women. Risks include birth defects in male fetuses if used in pregnancy, decreased libido, headache, gastrointestinal discomfort, and isolated reports of changes in menstruation, acne, and dizziness. Overall, 5-alpha reductase inhibitors were well-tolerated in both men and women, but not without risk, highlighting the importance of patient education prior to treatment.

5-Alpha reductase inhibitor use and prostate cancer survival in the Finnish Prostate Cancer Screening Trial

Randomized clinical trials have shown that use of 5α-reductase inhibitors (5-ARIs) lowers overall prostate cancer (PCa) risk compared to placebo, while the proportion of Gleason 8-10 tumors is elevated. It is unknown whether this affects PCa-specific survival. We studied disease-specific survival by 5-ARI usage in a cohort of 6,537 prostate cancer cases diagnosed in the Finnish Prostate Cancer Screening Trial and linked to the national prescription database for information on medication use. Cox proportional hazards regression was used to estimate hazard ratios and 95% confidence intervals for prostate cancer-specific deaths. For comparison, survival among alpha-blocker users was also evaluated. During the median follow-up of 7.5 years after diagnosis a total of 2,478 men died; 617 due to prostate cancer and 1,861 due to other causes. The risk of prostate cancer death did not differ between 5-ARI users and nonusers (multivariable adjusted HR 0.94, 95% CI 0.72-1.24 and HR 0.98, 95% CI 0.69-1.41 for usage before and after the diagnosis, respectively). Alpha-blocker usage both before and after diagnosis was associated with increased risk of prostate cancer death (HR 1.29, 95% CI 1.08-1.54 and HR 1.56, 95% CI 1.30-1.86, respectively). The risk increase vanished in long-term alpha-blocker usage. Use of 5-ARIs does not appear to affect prostate cancer mortality when used in management of benign prostatic hyperplasia. Increased risk associated with alpha-blocker usage should prompt further exploration on the prognostic role of lower urinary tract symptoms.

Obesity and Prostate Cancer

Prostate cancer is a complex, heterogeneous disease. Factors related to detection, particularly PSA screening, further increase heterogeneity in the manifestation of the disease. It is thus not possible to provide a simple summary of the relationship between obesity and prostate cancer. Findings on obesity, often defined using body mass index (BMI), and total prostate cancer risk have been mixed; however, obesity is relatively consistently associated with a higher risk of aggressive prostate cancer, with aggressiveness defined in various ways (e.g., advanced stage, fatal, poorer prognosis in men with prostate cancer). Many methodologic issues (e.g., influence of PSA screening, detection bias and treatment) need to be thoroughly considered in both existing and future etiologic and prognostic research. Biological mechanisms supporting the link are under investigation, but may involve insulin and IGF axis, sex steroid hormones and alterations in metabolism. Some promising data suggest that molecular sub-types of prostate cancer may offer insights into etiology, but further study is required. A full evaluation of body fatness and weight change over the life course would not only provide insights to the underlying mechanisms but also allow more effective interventions.

Combination of 5α-reductase inhibitor with combined androgen blockade (CAB) as a novel cytoreductive regimen before prostate brachytherapy: Ultra-CAB

We report a first case of using a 5α-reductase inhibitor (5ARI) and combined androgen blockade (CAB) as a cytoreductive regimen before prostate brachytherapy. Prostate volume reduction with CAB is limited to approximately 40% in most cases, making it difficult to meet anatomical constraints to perform these procedures in cases with large prostate volume. With the added administration of 5ARI, further volume reduction can be expected. Here, we describe this cytoreductive regimen used in a 63 year-old prostate cancer patient who became eligible to receive brachytherapy after dutasteride (0.5 mg daily) was added to CAB and prostate volume reduction of 57% was achieved.

BPH: a tell-tale sign of prostate cancer? Results from the Prostate Cancer and Environment Study (PROtEuS)

INTRODUCTION

In a population-based case-control study (PROtEuS), we examined the association between prostate cancer (PCa) and (1) benign prostatic hypertrophy (BPH) history at any time prior to PCa diagnosis, (2) BPH-history reported at least 1 year prior to interview/diagnosis (index date) and (3) exposure to BPH-medications.

METHODS

Cases were 1933 men with incident prostate cancer diagnosed across Montreal French hospitals between 2005 and 2009. Population controls were 1994 men from the same age distribution and residential area. In-person interviews collected socio-demographic characteristics and medical history, e.g., BPH diagnosis, duration and treatment, as well as on PCa screening. Logistic regression analyses tested overall and grade-specific associations, including subgroup analyses with frequent PSA testing.

RESULTS

A BPH-history was associated with an increased risk of PCa (OR 1.37 [95 % CI 1.16-2.61]), more pronounced for low-grade PCa (Gleason ≤6: OR 1.54 [1.26-1.87]; Gleason ≥7: OR 1.05 [0.86-1.27]). The association was not significant when BPH-history diagnosis was more than 1 year prior to index date, except for low-grade PCa (OR 1.29 [1.05-1.60]). Exposure to 5α reductase inhibitors (5α-RI) resulted in a decreased risk of overall PCa (OR 0.62 [0.42-0.92]), particularly for intermediate- to high-grade PCa (Gleason ≤6: OR 0.70 [0.43-1.14]; Gleason ≥7: OR 0.43 [0.26-0.72]). Adjusting for PSA testing frequency or restricting analyses to frequently screened subjects did not affect these results.

CONCLUSION

BPH-history was associated with an increased PCa risk, which disappeared, when BPH-history did not include BPH diagnosis within the previous year. Our results also suggest that 5α-RI exposure exerts a protective effect on intermediate and high-grade PCa.