GALVESTON, Texas – A new population-based study from The University of Texas Medical Branch at Galveston showed for the first time that exposure to testosterone therapy over a five-year period was not associated with an increased risk of aggressive prostate cancer. Further, risk of high-grade prostate cancer did not increase according to the total number of testosterone injections. The study is available in the Journal of Urology.

In view of the large increase in testosterone therapy use in recent years, examining the potential long-term risks of testosterone therapy holds increasing clinical and public health relevance.

Although several longitudinal studies have shown no increased risk of prostate cancer incidence associated with testosterone use, no population-based studies have examined the association of high-grade prostate cancer with testosterone exposure beyond one year.

Using SEER-Medicare linked data, the researchers identified 52,579 men who were diagnosed with prostate cancer between January 2001 and December 2006 and who had a minimum of five years continuous enrollment in Medicare before their cancer diagnosis. In the five years before their diagnosis, 574 men had a history of testosterone use. The distribution of age, ethnicity/race, year of diagnosis and marital status were comparable between testosterone users and nonusers.

The study analyzed data from diagnosis codes included in charges for outpatient and hospitalization services and physician claims.

Given the slow growth of prostate cancer development, this investigation offers novel and important information to physicians, patients and the general public,” said lead author Jacques Baillargeon, UTMB professor of epidemiology in the department of preventative medicine and community health. “This study’s findings offer important information regarding the risk-benefit assessment for men with testosterone deficiency who are considering treatment.”

Other authors of this paper include UTMB’s Yong-Fang Kuo, Xiao Fang and Vahakn B. Shahinian from the University of Michigan.

This research was supported by the National Institutes of Health and the UTMB Sealy Center for Vaccine Development.