New study below.
I know a number of men with PCa who are wary of 5-ARIs (5-Alpha Reductase Inhibitors). The two PCa prevention studies (Finasteride [Proscar] & Dutasteride [Avodart]) both reported a big reduction in lesser PCa, but an unexpected higher proportion of Gleason score 8-10.
The new (large) study looked at 5-ARI use men with BPH. As with the two mentioned studies, there was an: "increased prevalence of high-grade lesions at the time of diagnosis", but "5-ARI use was not associated with prostate cancer mortality ...".
To my mind, this is more evidence that detection bias explains the higher Gleasons. If there had been a PCa promotion effect, there would have been more deaths.
My bias: I am using Avodart.
Mayo Clin Proc. 2016 Dec;91(12):1717-1726. doi: 10.1016/j.mayocp.2016.07.023. Epub 2016 Oct 27.
5-Alpha Reductase Inhibitors and the Risk of Prostate Cancer Mortality in Men Treated for Benign Prostatic Hyperplasia.
Wallner LP1, DiBello JR2, Li BH3, Van Den Eeden SK4, Weinmann S5, Ritzwoller DP6, Abell JE7, D'Agostino R Jr8, Loo RK3, Aaronson DS4, Richert-Boe K5, Horwitz RI9, Jacobsen SJ3.
1Department of Medicine, University of Michigan, Ann Arbor, MI; Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA. Electronic address: email@example.com.
2Worldwide Epidemiology, GlaxoSmithKline, Collegeville, PA.
3Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA.
4Division of Research, Kaiser Permanente Northern California, Oakland, CA.
5Center for Health Research, Kaiser Permanente Northwest, Portland, ORG.
6Institute for Health Research, Kaiser Permanente Colorado, Denver, CO.
7Real World Evidence, Janssen, Philadelphia, PA.
8Department of Biostatistical Science, Wake Forest University, Winston-Salem, NC.
9Temple University, Philadelphia, PA; Institute of Medicine, Washington, DC.
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.
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).
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.
Copyright Â© 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
PMID: 28126151 DOI: 10.1016/j.mayocp.2016.07.023
[PubMed - in process]