What is the association between testosterone replacement therapy and advanced prostate cancer? Until now, previous research has indicated that use of TRT is associated with a higher risk of advanced (aggressive) disease, yet the authors of a new study have reported a novel finding—a lower risk of aggressive prostate cancer after one year of testosterone treatment.
For years, there has been conflicting findings concerning the impact of testosterone replacement therapy on the development of aggressive or advanced prostate cancer.
Experts have pointed to studies, albeit small ones with limited follow-up, in which men who took TRT did not go on to develop advanced disease. However, large studies of this phenomenon have been lacking.
This new case-control study used nationwide data from 38,570 prostate cancer cases and 192,838 age-matched men (controls) free of the disease. The data were provided by the National Prostate Cancer Register of Sweden. Of these men, 284 (1%) of patients and 1,378 (1%) of controls filled prescriptions for TRT.
Analysis of the data revealed the following:
- No association was found between use of TRT and overall risk of prostate cancer
- Men who took TRT had more favorable-risk prostate cancer and a lower risk of advanced prostate cancer than men who did not use TRT. (Favorable risk disease means having a lower risk of worsening disease.)
- The increase in favorable-risk disease was seen during the first year of testosterone therapy
- The lower risk of advanced prostate cancer was seen after men had been taking testosterone therapy for longer than one year
The authors of this new large study concluded that the increase seen in favorable-risk prostate cancer among men who elected to take testosterone replacement therapy indicates a detection bias, and that the decrease in the risk of advanced prostate cancer is a new finding that needs to be researched further.
Read more in our Prostate Cancer Health Center.
Reference
Loeb S et al. Testosterone replacement therapy and risk of favorable and aggressive prostate cancer. Journal of Clinical Oncology 2017 May 1; 35(13): 1430-36