"Most patients and their physicians are not aware of these important side effects," says lead author Matthew Smith, M.D., Ph.D., an MGH oncologist. "They assume that something else is wrong when they start gaining weight."
Smith explains that treatments aimed at lowering testosterone in prostate cancer patients are similar to strategies that lower estrogens in breast cancer patients. Sex hormones can accelerate the development of these cancers, and lowering or blocking them is an effective treatment approach. Unfortunately, the researchers found that lowering testosterone levels in men leads to increased weight, increase fat mass, and decreased muscle mass.
Smith and his colleagues studied forty men with nonmetastatic prostate cancer. The men received injections of leuprolide depot, a long-acting gonadotropin releasing hormone agonist, every 12 weeks for one year. In addition to increased fat body mass, the patients showed increased serum concentrations of total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides. Also, most subjects experienced anemia, with decreased blood hemoglobin concentrations.
Smith says patients may be able to modify their diet and exercise in order to offset these adverse effects of androgen deprivation therapy, but ultimately the long-term solution will be to develop better drugs for prostate cancer patients. "We need to develop improved strategies to prevent these side effects," he explains. "Our research program is evaluating whether other drugs will have fewer side effects."
Other co-authors of the study are Joel S. Finkelstein, M.D., Francis J. McGovern, M.D., Anthony L. Zietman, M.D., Mary Anne Fallon, L.P.N, and David A. Schoenfeld, Ph.D, of MGH, and Philip W. Kantoff, M.D., of the Dana Farber Cancer Institute. The study was supported by the National Institutes of Health, the Doris Duke Charitable Foundation, and CaP CURE.
The Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $300 million and major research centers in AIDS, the neurosciences, cardiovascular research, cancer, cutaneous biology, transplantation biology and photo-medicine. The Department of Molecular Biology at MGH also conducts basic research including plant molecular biology and genomics. In 1994, the MGH joined with Brigham and Women?s Hospital to form Partners HealthCare System, an integrated health care delivery system comprising the two academic medical centers, specialty and community hospitals, a network of physician groups and nonacute and home health services.
Journal
Journal of Endocrinology and Metabolism