According to an article recently published in the Journal of the American Medical Association, androgen suppression therapy (AST), also referred to as androgen deprivation therapy, in addition to radiation therapy improved survival in some men with early prostate cancer. This improvement was limited to men with high-risk prostate cancer and those without other significant medical conditions.
Early prostate cancer refers to prostate cancer that has not spread from the prostate to distant sites in the body but is limited to the prostate and nearby lymph nodes. Standard therapy for early prostate cancer may include surgery, radiation therapy, watchful waiting (no treatment until disease progression), and hormone therapy. Optimal treatment for early prostate cancer is still under debate, though it appears that individualized approaches may provide the best outcomes. Several variables are considered when selecting treatment options for early prostate cancer; these include age, aggressiveness of cancer, extent of spread, other existing medical conditions, and side effects of therapy.
Prostate cancer is stimulated to grow from exposure to the male hormone testosterone. Androgen suppression therapy, also referred to as hormone therapy, reduces the amount of circulating testosterone, which ultimately reduces the growth stimulus of prostate cancer. Studies have suggested that AST benefits patients with early prostate cancer. Side effects of AST, however, must be weighed against its benefits.
Researchers from Brigham and Women’s Hospital and Dana Farber Cancer Institute recently conducted a clinical trial to evaluate which subgroups of patients with prostate cancer might benefit from the addition of AST to their treatment regimen. This trial included 206 men with early but aggressive prostate cancer who were to receive treatment with either radiation therapy alone or radiation therapy combined with six months of AST. Median follow-up was 7.6 years.
- Men treated with AST plus radiation therapy had significantly improved survival compared with men treated with radiation therapy only.
- This benefit was, however, limited to men without other significant existing medical conditions. Men who had other significant existing medical conditions did not gain a survival benefit with the addition of AST to radiation therapy compared with radiation therapy only.
The researchers concluded that AST in addition to radiation therapy does provide a survival benefit among men with early, aggressive prostate cancer. It appears, however, that this benefit is limited to men without other significant existing medical conditions. Further study is necessary to confirm these findings.
Patients with early prostate cancer may wish to speak with their physician regarding their individual risks and benefits of all treatment options. Two sources of information regarding ongoing clinical trials include the National Cancer Institute (www.cancer.gov) and www.eCancerTrials.com.
Reference: D’Amico A, Chen M-H, Renshaw A, Loffredo M, Kantoff P. Androgen suppression and radiation vs radiation alone for prostate cancer. Journal of the American Medical Association. 2008;299:289-295.