Is anti-androgen monotherapy just as good as ADT with LHRH agonists in terms of overall survival?

Anti-androgen (AA; i.e., drugs like Casodex) monotherapy and LHRH agonists (e.g., Lupron and Zoladex) are two options for hormone therapy, but with quite different mechanisms of action. LHRH agonists are general thought to have more severe side effects. It is a controversial issue though as to whether AA monotherapy is as safe as LHRH agonists. AA monotherapy is more popular in Europe, but far less commonly used in North America becuase of concern about overall mortality.

Recently researchers in Sweden undertook an observational study to compare differences in mortality for men treated with either AA monotherapy versus LHRH agonists. They used a Swedish Prostate Cancer database to compare survival for 2,078 men treated with AA versus 4,878 men treated with LHRH agonists. All men were diagnosed with advanced, non-metastatic prostate cancer.

Surprisingly the two treatments had very similar prostate cancer-specific mortality. In fact, the cumulative 5-year prostate cancer mortality was slightly lower for men treated with AA monotherapy (16% versus 22%). Furthermore, all-cause mortality was lower for men treated with AA monotherapy (17% versus 27%).

One caveat on this study is that the two populations were not identical; i.e., the men on AA were generally younger, diagnosed more recently, had less adverse cancer characteristics, and more education. This selection bias was noted and addressed statistically. The researchers suggest that using AA monotherapy as a primary hormonal therapy and reserving LHRH agonists to a later date may help men to avoid the more bothersome side effects of LHRH agonists.


For more information, or to read the full article, follow the link below:

Thomsen, F. B., Bosco, C., Garmo, H., Adolfsson, J., Hammar, N., Statttin, P., & Van Hemelrijck, M. (2018). Anti-androgen monotherapy versus gonadotropin-releasing hormone agoinists in men with advanced, non-metastatic prostate cancer: A register-based, observational study. Acta Oncologica [Epub ahead of print]. doi: 10.1080/0284186X.2018.1529427