Fluctuations in testosterone levels may predict prostate cancer risk

Dr. David Samadi gives his expert opinion on a new study suggesting unstable testosterone or a significant drop in this hormone may act as a strong risk factor for developing prostate cancer.

A study out of Germany and published in the Journal of Urology, found men who had a drop in their testosterone level at a younger age or who experienced large variations in testosterone levels were more likely to develop prostate cancer. 

“This study brings up an interesting concept of how a man’s testosterone levels may influence their risk of the second most common cancer diagnosed in American men,” stated Dr. David Samadi.  “Testosterone is the most abundant androgen in men and we know that as a man ages, his testosterone levels begin to decrease by approximately 3.2 to 3.5 ng/dl per year in healthy middle-aged men.  This decline can result for some men in hypogonadism with symptoms of a low sex drive and trouble of erectile dysfunction.”

This relatively small study followed 376 men, aged 45 to 74 years, from 2004 to 2016 with testosterone levels less than 12.1 nmol/L who had opted against testosterone replacement therapy.  The aim of the study was to investigate whether dynamic patterns of testosterone levels contributed to an increased risk of prostate cancer.

“Development of the prostate along with its growth and function relies on testosterone,” explained Dr. Samadi.  “We have known that there is a relationship between testosterone and the progression of prostate cancer being driven by androgens such as testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S).  Without androgens, prostate cancer cannot grow or survive.  It was in 1941 when androgen-deprivation therapy (ADT) with surgical or pharmacological castration began to be used as a form of treatment for prostate cancer and has continued to be a mainstay of treatment ever since.  But the exact role testosterone plays in the development of prostate cancer is not completely understood.”

The researchers with the study found that the older a man was when his total testosterone fell to 12.1 nmol/L or below, the lower his lifetime risk of prostate cancer with the risk declining by 32% for each 1-year increase in age at diagnosis. Another factor found was that men with a high versus low coefficient of variation, which is a measure of testosterone fluctuation over time, had 4.9 times the risk of developing prostate cancer.  Men with a maximum drop in testosterone that differed by 20% or more from his average or who had a large median drop within 2 years had 8.5 and 2.7 times greater risks, respectively. 

“The important relevant information from this study indicates that there appears to be an association between dynamic patterns of testosterone and prostate cancer development,” exclaimed Dr. Samadi.  “If a man experiences abnormal drops in his testosterone levels, this might be disrupting the environment within the prostate leading to the prostate having to adapt to the lowered levels of testosterone.  This might be make cells within the prostate more sensitive to testosterone possibly giving rise to the development of prostate cancer.”

Dr. Samadi explained further.  “The message from this study points to the fact that maintaining stable testosterone levels may have a significant impact on preventing prostate cancer.  This means physicians should regularly monitor the level of testosterone in men at an earlier age in life starting between 40 to 50 years of age to establish a baseline.  With routine monitoring, it makes it easier to spot changes such as abnormal variations or declines and getting a man the proper treatment he needs such as testosterone therapy to reduce the development of prostate cancer.  Since every man is unique, testosterone therapy should be tailored to restore levels back to a man’s normal range once any variations in testosterone is detected.  This can be accomplished by taking into consideration each man’s need regarding the timing and dose of testosterone therapy to help reach the best beneficial effect of testosterone on preventing prostate cancer.”

Patients newly diagnosed with prostate cancer can contact world renowned prostate cancer surgeon and urologic oncologist, Dr. David Samadi, for a free phone consultation and to learn more about prostate cancer risk, call 212-365-5000.