Men who take testosterone supplements should be screened regularly for prostate cancer, according to a report published in The Journal of Urology.
Testosterone is a male hormone produced mainly by the testes. Since it is known to stimulate the growth of some prostate cancers, effective treatments for prostate cancer include suppression of testosterone levels by surgical removal of the testes or treatment with testosterone-lowering drugs. Given this link between testosterone and prostate cancer, there is interest in understanding whether use of testosterone supplements to treat sexual dysfunction or for “rejuvenation” increases a man’s risk of prostate cancer. This is a particularly important question for older men, who are the most likely to receive testosterone supplements and most likely to have undetected prostate cancer that could be stimulated by testosterone.
To describe the characteristics of prostate cancer in men taking testosterone, researchers reviewed 20 cases of prostate cancer that developed among men undergoing testosterone therapy. A majority of these cancers developed during the first two years on testosterone, and roughly one-third developed in the first year. Prostate cancer was detected by abnormalities in both prostate-specific antigen (PSA) levels and findings on digital-rectal exam (DRE) in 40% of men, by abnormal DRE alone in 35% of men, and by elevated PSA alone in 25% of men.
Screening for prostate cancer before treatment with testosterone varied across patients. All of the men who received their testosterone prescription from a urologist were screened for prostate cancer with PSA and DRE before starting testosterone. Of the men who received their testosterone prescription from another type of doctor, 75% had a PSA test, but only 25% had a DRE before starting testosterone.
Based on this review of 20 patients who developed prostate cancer while taking testosterone supplements, the researchers recommend that PSA testing and DRE be performed frequently during testosterone treatment. Because this report describes only men who developed prostate cancer while on testosterone, without providing information about men who did not develop prostate cancer while on testosterone, it is not possible to draw conclusions from this study about whether, and by how much, testosterone supplements increase the risk of prostate cancer.
But given a plausible link between testosterone and prostate cancer, men who take testosterone supplements may wish to talk with their doctor about their prostate cancer risk and the recommended frequency of prostate cancer screening. Additional studies are underway to better understand the link (if any) between testosterone supplementation and risk of prostate cancer.