In the first study of its kind, researchers at Brigham and Women's Hospital (BWH) and Dana-Farber Cancer Institute (DFCI) have found that combined radiation therapy (RT) and androgen suppression therapy (AST) is a more effective treatment for localized early-stage prostate cancer compared to treatment using radiation therapy alone.
AST is a type of hormonal therapy that is often used in all phases of prostate cancer treatment to help block production or action of the male hormones that have been shown to fuel prostate cancer.
The findings are published in today's issue of JAMA (the Journal of the American Medical Association).
"Previous studies have shown a benefit to treating advanced-stage prostate cancer with radiation and hormone therapy," said Anthony V. D'Amico, MD, PhD, of BWH and DFCI. "This is the first study to show that the combination treatment may also benefit people with early-stage cancer."
Prostate cancer is the second leading cause of cancer death among men in this country. The American Cancer Society estimates that about 184,500 American men will be diagnosed with the disease this year and 39,200 will die.
In the study, researchers compared the relative risk of prostate specific antigen (PSA) failure during a five-year period in men who underwent RT and AST as treatment for diagnosed early-stage prostate cancer compared with men who received RT.
Although no significant difference between treatment groups was found in patients in the low-risk category, men who were classified in the intermediate-risk group and received both therapies for their cancer were five times less likely to have PSA failure than men who received RT alone.
For men in the high-risk group who received both RT and AST, the effectiveness of combination therapy was more profound; they were two and one-half times less likely to have PSA failure than men who had received RT.
"While further research is needed, it appears that the one-two punch of RT and AST may be a more effective treatment in the battle against both advanced-stage and early-stage prostate cancer," added Dr. D'Amico.
The 1,586 study participants were categorized using a combination of their PSA levels, biopsy Gleason score, and stage of tumor, into three groups. All patients in the study had cancer that was localized to the prostate by rectal exam. The more aggressive the participant's tumor, the higher the risk category in which he was placed. The men's cancers were treated using a three-dimensional conformal RT with or without AST.
BWH is a 716-bed nonprofit teaching affiliate of Harvard Medical School and a founding member of Partners HealthCare System, an integrated health care delivery network. Internationally recognized as a leading academic health care institution, BWH is committed to excellence in patient care, medical research, and the training and education of health care professionals.
The hospital's preeminence in all aspects of clinical care is coupled with its strength in medical research. A leading recipient of research grants from the National Institutes of Health, BWH conducts internationally acclaimed clinical, basic and epidemiological studies.
[Contact: Todd D. Ringler]