The New England Journal of Medicine | Oct 25, 2012
The utility of (prostate-specific antigen) PSA screening to inform prostate cancer diagnosis and treatment has been a topic of heated debate. The New England Journal of Medicine (NEJM) conducted a poll that indicates a lack of consensus among clinicians regarding best prostate cancer screening practices. Many clinicians feel patients should make informed decisions regarding testing preferences.
In a recent phase III clinical trial, the anti-androgen drug abiraterone (sold as Zytiga) improved survival from 11.2 months to 15.8 months in patients with castration-resistant prostate cancer (CRPC). Participants were treated with abiraterone in combination with prednisone, a common steroid medication. The most common side effects were fatigue, anemia, and back and bone pain.
The FDA has approved enzalutamide (sold as Xtandi) 3 months ahead of deadline. The drug improved survival by nearly 5 months in men with advanced prostate cancer. It is approved for individuals who have not responded to chemotherapy. However, manufacturers hope to expand approval to include patients not previously treated with chemotherapy.
A recent study evaluated androgen deprivation therapy with and without radiation therapy in individuals with locally advanced prostate cancer. Individuals who received combination treatment had a better overall survival rate. Bowel-related side effects were similar for both groups 24 months after treatment.
Researchers at the Fox Chase Cancer Center have identified a relationship between testosterone levels after radiation therapy and the risk of prostate cancer recurrence in a small number of patients. They found that individuals with a significant drop in testosterone were more likely to see a rise in prostate-specific antigen (PSA), possibly indicating recurrence. Further studies need to be conducted.
In a phase I clinical trial, a new drug that specifically targets prostate cancer cells has shown promising results. The drug, which combines an antibody protein that targets prostate cancer cells with a cancer-killing drug, has shown antitumor activity in advanced prostate cancer. A phase II clinical trial is being held to further evaluate the drug.
A recent study evaluated the effects of beta-carotene antioxidant supplements in patients undergoing radiation therapy for advanced prostate cancer. Researchers were concerned that the supplements could reduce the benefits of radiation. The study followed participants for 10 years and did not find a difference in progression to lethal prostate cancer in individuals who took beta-carotene and those who did not.
Focal laser thermal therapy (FLTT) is being studied at the Princess Margaret Hospital in Toronto for treating men with low- to intermediate-risk prostate cancer. The procedure uses a focal laser to kill cancer cells, while sparing surrounding tissue and decreasing the risk of unwanted side effects. A phase III clinical trial is planned to start in the near future.
Accuray Incorporated announced positive data for CyberKnife stereotactic body radiation therapy (SBRT) for the treatment of cancer confined to the prostate. Several studies indicate that SBRT is as effective and possibly less toxic than traditional radiotherapy. Treatment with SBRT was effective with far fewer treatment sessions than are often required with traditional radiotherapy.