Prostate Cancer Hormone Therapy Raises Risk of Heart Disease and Diabetes

By Rachael Myers Lowe

(September 19, 2006) - A large study concludes widely used hormone therapy for prostate cancer survivors increases their risk of developing heart disease and diabetes.

Study author Dr. Nancy Keating of the Harvard Medical School cautions: “Patients and physicians need to be aware of the elevated risk as they make treatment decisions.”  

An estimated 234,000 American men will be diagnosed with prostate cancer this year.  Because of new screening techniques, many of them will be diagnosed with cancer limited to the prostate or to the prostate and its immediate region. Such early disease is treated primarily with surgery alone or with radiation therapy.

An increasing number of these men are also put on hormone therapy to reduce the risk of the disease coming back or spreading in the case some cancer cells escaped initial treatment. Hormone therapy (androgen suppression or GnRH agonist therapy) stops the body’s production the sex hormone testosterone which prostate cancer uses to grow.

Most patients with advanced disease are prescribed hormone therapy to slow down their cancer’s growth. Because men with more advanced disease have benefited from hormone therapy, many men with early disease treated with radiation are also given a two to three year course of androgen suppression therapy. 

“Men with prostate cancer have high five-year survival rates, but they also have higher rates of non-cancer mortality than healthy men,” Dr. Keating said in urging a more cautious approach to prescribing hormone therapy to men with early stage prostate cancer.

Dr, Keating and colleagues examined the treatments given 73,000 prostate cancer patients aged 66 or older diagnosed with early stage disease.

“Our study found that men with local or regional prostate cancer receiving a GnRH agonist had a 44%  higher risk of developing diabetes and a 16%  higher risk of developing coronary heart disease than men who were not receiving hormone therapy,” Dr. Keating said.

“Doctors should think twice about prescribing GnRH agonists in situations for which studies have not demonstrated improved survival until we better understand the risks of treatment,” said study co-author Matthew Smith, MD, a medical oncologist at Massachusetts General Hospital.

Other side effects of androgen deprivation therapy have been well documented including loss of bone mass, hot flashes, change in weight, and memory loss.

The research is published in the September 20^th edition of Journal of Clinical Oncology.

SOURCE: 

• Journal of Clinical Oncology, September 20.
• Harvard Medical School Press release.