A recently completed study followed prostate cancer patients for 10 years to determine the effects of radiation therapy after removal of the prostate gland (prostatectomy). Fifty-six percent of patients who received radiotherapy after prostatectomy did not have detectable prostate cancer at 10 years, compared to 35% who did not receive radiotherapy. These results are similar to results of previous studies.
Two new targeted therapies for castration-resistant prostate cancer (CRPC), aflibercept and dasatinib, did not prove to be effective in phase III clinical trials. Both drugs showed promise in preclinical trials but, when tested in combination with chemotherapy, neither drug improved overall survival. Additionally, patients who took aflibercept had worse side effects than those who took a placebo.
New findings from two prostate cancer trials will be presented at the American Society of Clinical Oncology Annual Meeting. One trial determined that men with advanced prostate cancer who receive intermittent hormone therapy survive an average of 5.1 years compared to 5.8 years for men who receive therapy continuously. The second trial determined that abiraterone (Zytiga) in combination with prednisone (a steroid) was effective for the treatment of castration-resistant prostate cancer (CRPC) in patients who have not yet received chemotherapy. Abiraterone is currently approved for patients who have not responded to chemotherapy.
A clinical trial found that dabrafenib, a BRAF inhibitor, was far more effective in treating melanomas that have BRAF mutations than the chemotherapy drug dacarbazine, according to a report at an American Society of Clinical Oncology meeting. Patients treated with this drug lived without getting worse for 70% longer than those treated with dacarbazine (5.1 vs. 2.7 months, respectively). Moreover, compared to those treated with vemurafenib in other studies, dabrafenib-treated patients had less risk of another kind of skin cancer called squamous cell carcinoma. This suggests that dabrafenib, which is experimental, could be safer than vemurafenib, which is FDA approved.