About one-third of men with localized, high-risk prostate cancer who received the drug abiraterone (Zytiga) along with hormone therapy before surgery had little to no cancer remaining after six months of treatment, according to a recent clinical trial. Prostate cancer is called localized high-risk prostate cancer when the tumor has grown throughout the prostate, is high grade (meaning the cancer cells barely look like normal cells, called a Gleason score of 8), and the man has a prostate-specific antigen (PSA) level higher than 20.
Men with this type of prostate cancer often have a poor prognosis (chance of recovery) because the cancer often spreads to other parts of the body even with treatment. Hormone therapy lowers levels of the hormone testosterone, which prostate cancers use to grow and spread. Abiraterone also blocks the production of testosterone, which means that these two treatments together may be more effective to stop prostate cancer growth. Abiraterone has been used to treat advanced prostate cancer, but this is the first time it has been studied for earlier-stage prostate cancers.
In this study, researchers combined abiraterone with leuprolide (Lupron, Viadur), a standard hormone therapy for prostate cancer, for two groups of men with localized, high-risk prostate cancer. One group included 27 men who received leuprolide for 12 weeks, followed by another 12 weeks of leuprolide plus abiraterone. The second group included 29 men who received both abiraterone and leuprolide for 24 weeks. After treatment was finished, all of the men in the study had surgery to look for any cancer remaining in the prostate.
Of the men who received 24 weeks of abiraterone and leuprolide, 34% had little to no cancer remaining in the prostate. For the men who received 12 weeks of abiraterone plus leuprolide, 15% had little to no cancer remaining in the prostate. These results indicate that the longer combination of abiraterone and leuprolide may work better to treat this type of prostate cancer.
What this means for patients
"For this many patients with high-risk disease to have very little to no cancer in the prostate after six months of treatment is dramatic,” said lead author Mary-Ellen Taplin, MD, Associate Professor of Medicine at Harvard Medical School and the Dana-Farber Cancer Institute in Boston, Massachusetts. “Our findings suggest that this combination could improve outcomes for many men, but larger, long-term studies are needed." Talk with your doctor to learn more about all treatment options for prostate cancer, including clinical trials.
Questions to ask the doctor
- What stage of prostate cancer do I have? What does this mean?
- What are my treatment options?
- Will hormone therapy be used? What other treatments are needed?
- What is my prognosis?
- What are the side effects of the recommended treatments?
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