That's the verdict from a new review of 18 studies on the topic.
The reviewers pooled data from all 18 studies, which totaled more than 10,000 men.
When the studies began, none of the men had prostate cancer . They were 46 72 years old, on average, at the time. Researchers measured sex hormone levels in the men's blood samples.
Nearly 3,900 of the men were diagnosed with prostate cancer by the time the studies ended; 90% of those men developed prostate cancer after age 60 and after being followed for at least seven years.
Blood levels of testosterone and other sex hormones weren't associated with prostate cancer risk. That is, a man's blood levels of those hormones at the study's start didn't seem to make him more or less likely to develop prostate cancer.
The reviewers -- who included Andrew Roddam, DPhil, of England's Oxford University -- report their findings in the Feb. 6 edition of the Journal of the National Cancer Institute.
Based on their work, an editorial published with the study urges the scientific community to "get on with the difficult task of exploring, analyzing, and characterizing modifiable risk factors for prostate cancer."
The editorialists included William Carpenter, PhD, of University of North Carolina at Chapel Hill's School of Public Health.
By Miranda Hitti
Reviewed by Louise Chang
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