What is Testosterone Replacement Therapy?
Testosterone replacement therapy is the use of testosterone supplements to restore testosterone levels to a normal range in men who have a deficiency of the hormone. This therapeutic approach can be used to treat erectile dysfunction that is associated with a testosterone deficiency, and to treat symptoms of andropause (male menopause). Testosterone replacement therapy should not be used unless a man has a verified deficiency of testosterone.
To get the most accurate reading of your testosterone levels, a saliva test is recommended. A blood (serum) test does not measure all the hormone that is carried by red blood cells, and thus doctors could prescribe a dose that is too high.
Bio-identical testosterone gel or cream is the best way to get the hormone into your system. The term “bio-identical” means that the hormone is biochemically the same as the hormone the body produces naturally. Synthetic hormones are drugs and are foreign to the body, so the body essentially does not treat them like hormones. Because synthetic hormones are not true hormones, they do not provide the same benefits as the real thing.
A testosterone cream or gel allows the hormone to be absorbed through the skin and into the blood without having to pass through the liver, as an oral dose would have to do. Oral testosterone goes through the liver and 90 percent becomes bound to protein, severely limiting its effectiveness. Transdermal testosterone is at least 10 times more efficient than oral dosing. A compounding pharmacy can make up a testosterone cream that will provide you with the right dose to bring you back into balance.
Can Testosterone Replacement Therapy Cause Cancer?
One of the pressing questions men ask when faced with the possibility of starting testosterone hormone therapy is, “Can testosterone replacement therapy cause cancer?” Up until recently, this question would likely have been answered by most doctors with a resounding “yes.”
However, a great deal of research has been done to determine whether the “yes” response to the question about testosterone therapy and prostate cancer is accurate, and based on accumulating evidence, it appears the answer is “no.” One compelling reason for the “no” response can be attributed to the comprehensive investigative work done by Abraham Morganthaler, MD, FACS, author of Testosterone for Life, who evaluated the original work by urologist Charles Higgins in the 1940s, research that led to the misconception that taking testosterone can cause prostate cancer.
Morganthaler discovered that this idea arose out of one case study involving one patient. In other words, the fear that testosterone therapy can cause prostate cancer was based on nothing. In fact, in recent years there have been many studies that dispel the myth that testosterone replacement therapy causes prostate cancer or has a significant negative impact on the prostate. For example:
- A Beth Israel Deaconess Medical Center review of 72 studies (Rhoden 2004) found “no compelling evidence that testosterone replacement therapy increases the incidence of prostate cancer.”
- A report by The Prostate Cancer Center Hamburg-Eppendorf in Germany. (Isbarn 2009) stated “the available research strongly suggested that testosterone therapy neither increases the risk of prostate cancer in normal men nor causes a recurrence of the cancer in men who have been treated successfully for prostate cancer.”
- In a study of 57 men who received testosterone supplementation for an average of 36 months after prostatectomy surgery, although mean testosterone levels rose in all the men before testosterone therapy, there was no increase in PSA values after testosterone therapy started. So, testosterone replacement therapy caused hormone levels to rise, PSA values to remain the same, and symptoms to be relieved. Baylor College of Medicine study (Khera 2009)
- A study conducted within the ongoing Osteoporotic Fractures in Men cohort looked at the association between testosterone, estradiol, estrone, and sex hormone-binding globulin and prostate cancer. Only estrone was strongly related to an increased risk of prostate cancer. University of California, San Francisco (Daniels 2010)
- In a landmark study reported in 2006, men who had low testosterone levels were given testosterone injections or placebo every two weeks for six months. Before and throughout the study, the investigators took measurements of testosterone and DHT from both blood samples and the prostate itself. The researchers found that although blood concentrations of testosterone and DHT rose substantially in men who were given hormone replacement therapy, the concentration of testosterone and DHT did not change at all in the prostate gland. In addition, testosterone therapy had no effect on biochemical markers of prostate cell growth. Therefore, the authors noted that while testosterone replacement therapy normalized blood levels of testosterone, treatment did not affect prostate tissue or prostate cell functions. According to Morganthaler, “it is as if once the prostate has been exposed to enough testosterone, any additional testosterone is treated as excess and does not accumulate in the prostate.” To state it another way, he said “we say the prostate has been saturated with regard to testosterone.” (Marks 2006; Morganthaler 2008)
According to a Johns Hopkins Prostate Disorders Special Report, “Testosterone-Replacement Therapy: Does It Increase Prostate Cancer Risk?” the jury is still out on whether testosterone replacement therapy is safe when men take it for a prolonged time. Morganthaler would take that a step further, as he has noted that “The relationship of testosterone to prostate cancer has undergone a significant reevaluation, and all recent evidence has reinforced the position that testosterone therapy is safe for the prostate.”
In addition, if you already have prostate cancer, the concern has been that taking testosterone could make the cancer progress faster, or that the hormone could promote tumor growth. These worries are the reasons why some doctors will not prescribe testosterone therapy for men who have a history of prostate cancer.
Morganthaler explains why this is not a concern by referring to the study by Marks and the point about how “once the prostate has been exposed to enough testosterone, any additional testosterone is treated as excess and does not accumulate in the prostate.”
Basically, when men have very low testosterone levels, prostate growth is hypersensitive to any change in the concentration of testosterone. Therefore, while severely reducing testosterone levels (as is done in men with prostate cancer who undergo hormone ablation therapy) will cause prostate cancer to shrink, giving testosterone can cause prostate cancer to regrow. “However,” Morganthaler notes, “once we get above the point where the prostate is saturated with testosterone, adding more testosterone will have little, if any, further impact on prostate cancer growth. Experimental studies suggest the concentration at which this saturation occurs is quite low.”
Testosterone Replacement Therapy and the Women’s Health Initiative
Another reason why many doctors are reluctant to prescribe testosterone replacement therapy is related to the Women’s Health Initiative (WHI) results. For years, postmenopausal women were prescribed hormone replacement therapy to relieve symptoms brought on by the dramatic decline in estrogen associated with menopause. Women were also told that hormone therapy would help prevent osteoporosis and reduce their risk of heart disease.
But when the WHI results were announced, it was learned that hormone-replacement therapy raised the risks of cardiovascular disease, breast cancer, stroke, and blood clots. Sure, it relieved menopausal symptoms—but at what cost. Today, hormone-replacement therapy is prescribed only for postmenopausal women who are experiencing distressing symptoms, and then usually, for only a very short time.
Experts do not want to make the same mistake with testosterone replacement therapy. So far it appears testosterone replacement therapy is useful and safe for some men who have a testosterone deficiency and who have been treated for prostate cancer.
However, if you are considering testosterone replacement therapy:
- You should be monitored closely for any rise in PSA levels and/or return of prostate cancer
- Avoid synthetic testosterone. Instead, ask your healthcare provider about bio-identical testosterone therapy. This form of the hormone mimics the activity of the testosterone naturally produced by the body.
- Your physician needs to balance testosterone with estradiol, because the proper ratio of testosterone to estradiol is necessary for prostate (and overall) health
Another fear associated with taking testosterone is that when a man first takes the hormone, the prostate reacts very quickly and begins to grow. This increase in size usually stops after the first few months of treatment, so the prostate gland typically ends up being no larger than it was before the hormone level began to drop. Bottom line: the increase in prostate size resulting from testosterone therapy is not usually sufficient to cause any of the urinary symptoms associated with benign prostatic hyperplasia or to worry about the development of prostate cancer as numerous well-run studies have shown, and as Morganthaler explained above, testosterone does not increase the risk of prostate cancer.
Additional references
Marks LS et al. Effect of testosterone replacement therapy on prostate tissue in men with late-onset hypogonadism: a randomized controlled trial. JAMA 2006 Nov 15; 296(19): 2351-61
Morganthaler A. Destroying the myth about testosterone replacement therapy and prostate cancer. Life Extension 2008 December.
