Hormone Therapy For Prostate Cancer Causes Weight Gain

11 April 2002
Hormone Therapy For Prostate Cancer Causes Weight Gain
by George Atkinson

Prostate cancer patients often receive androgen-deprivation therapy to reduce their levels of the hormone testosterone, but the side effects have not been well studied. A Massachusetts General Hospital (MGH) study published in the February issue of The Journal of Clinical Endocrinology and Metabolism reveals that unwanted weight gain, particularly increased fat body mass, is a common occurrence in these patients. "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."