Endogenous and exogenous testosterone and the risk of prostate cancer and increased prostate-specific antigen (PSA) level: a meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of prospective cohort studies and randomized controlled trials
PubMed 26779889 · doi:10.1111/bju.13417
What was done
A systematic review and meta-analysis conducted under PRISMA guidelines evaluating the link between testosterone (endogenous and exogenous) and prostate cancer or PSA. The authors searched prospective cohort studies for endogenous testosterone and placebo-controlled randomized trials of testosterone replacement therapy (TRT). Pooled effect estimates were calculated using random-effects models, testing for heterogeneity and publication bias.
What was found
From 20 prospective cohort estimates, the summary relative risk (SRR) of prostate cancer per 5 nmol/L increase in endogenous testosterone was 0.99 (95% CI 0.96 to 1.02; I² = 0%). Across 26 randomized trials, the difference in PSA levels following TRT onset was 0.10 ng/mL (95% CI -0.28 to 0.48), with consistent findings across subgroups (administration route, baseline testosterone, age, trial duration). In 11 trials reporting prostate cancer as an adverse outcome, the SRR for TRT was 0.87 (95% CI 0.30 to 2.50).
Why it matters
These findings challenge the long-held assumption that higher testosterone levels promote prostate cancer development and provide reassurance regarding the safety of TRT for symptomatic hypogonadism.
Limits
The abstract does not report the total participant counts. The prostate cancer risk estimate from TRT trials was based on only 11 studies and had a very wide confidence interval (0.30 to 2.50), reflecting low event rates and limited trial follow-up durations.
Cited by
- supports Testosterone replacement therapy does not increase the risk of cancer.