According to results recently published in The New England Journal of Medicine, testosterone replacement therapy for the treatment of hypogonadism does not appear to increase the risk of developing prostate cancer.

Hypogonadism, which is thought to occur in 2-4 million men in the United States, is a condition in which low levels of the male hormone testosterone are produced. Symptoms of hypogonadism include a reduced sexual drive, erectile dysfunction, low levels of red blood cells (anemia), reduced bone density, reduced muscle mass, and depression. Treatment for hypogonadism often includes the use of synthetic testosterone to replenish low levels in the patient. However, recent concern has arisen over the risk that testosterone replacement therapy may place on the incidence of prostate cancer. This concern has been fueled by the fact that the reduction of testosterone levels in men with prostate cancer, referred to as hormonal therapy, tends to produce anti-cancer responses.

Researchers from Brazil recently analyzed data from a compilation of published studies involving men who were treated with testosterone-replacement therapy. These studies involved 461 men treated with testosterone for hypogonadism. Follow-up of these patients was between 6 to 36 months. Overall, during this follow-up period, 5 men (1.1%) developed prostate cancer. This is similar to rates of prostate cancer in the general population. However, there has been no follow-up greater than 36 months. In addition, other studies have failed to demonstrate a difference in levels of testosterone taken from frozen blood samples between men who developed prostate cancer compared to those who did not develop prostate cancer 7 to 25 years after the sample was taken.

The researchers concluded that testosterone replacement therapy for hypogonadism does not appear to play a role in the development of prostate cancer. However, there was no data following 36 months of follow-up in the patients analyzed, leading to the possibility that longer follow-up may refute these findings. The researchers recommend that prostate specific antigen (PSA) testing and digital rectal exams should be practiced in patients treated with testosterone therapy in order to screen for the development of prostate cancer. Patients with hypogonadism may wish to speak with their physician about the risks and benefits of testosterone-replacement therapy in their individual situation, and the scheduling of screening for prostate cancer.

Reference: Rhoden E, Morgentaler A. Risks of testosterone-replacement therapy and recommendations for monitoring. The New England Journal of Medicine. 2004;350:482-492.