The theory is that since most prostate cancer cell lines need testosterone to proliferate, it is better not to replace the testosterone that is lost with aging. The problem with this theory is that most men who contract prostate cancer have low levels of testosterone, and the majority of published studies show that serum testosterone levels do not affect one's risk for contracting prostate cancer. The appendix at the end of this article provides quotations from the published literature as it relates to the issue of whether testosterone causes prostate disease. One study was considered neutral. Before anyone starts a testosterone replacement program, he should have a serum PSA test and a digital rectal exam to rule out prostate cancer.
Nothing is risk free.
A small minority of men with low testosterone and prostate cancer will not have an elevated PSA or palpable lesion detectable by digital rectal exam. If these men use supplemental testosterone, they risk an acute flare-up in their disease state. That is why PSA monitoring is so important every 30 to 45 days during the first 6 months of any type of testosterone augmentation therapy. If an underlying prostate cancer is detected because of testosterone therapy, it is usually treatable by nonsurgical means. We acknowledge that some aging men will not want to take this risk.