MONDAY, Feb. 1, 2010 (HealthDay News) -- Men with prostate cancer and the physicians who treat them are being warned that the androgen-deprivation therapy (ADT) commonly used against the malignancy might increase the risk of heart attack and cardiac death.
"There is a substantial amount of data demonstrating that ADT adversely affects traditional cardiovascular risk factors, including serum lipoproteins, insulin sensitivity and obesity," according to an advisory published online Feb. 1 in Circulation by a group of experts from the American Heart Association, American Cancer Society and the American Urological Association.
The warning is guarded, saying that risks have not been found in all studies. "But we think that physicians treating patients with localized and metastatic prostate cancers as well as patients ought to realize that there are significant risks associated with the use of hormone therapy," said Dr. Otis Brawley, chief medical officer of the American Cancer Society.
ADT reduces or eliminates the male hormones that can promote growth of prostate cancer. About one-third of all men with prostate cancer are given ADT, Brawley noted.
"Many people underestimate the harm of hormonal therapy and overestimate the potential benefits of hormonal therapy," he said.
Six studies -- two done in Europe, four in the United States -- have shown increased incidence of cardiovascular problems in men, Brawley said.
One U.S. study of 37,000 men treated for prostate cancer at Veterans Affairs hospitals found a 27 percent increased risk for heart disease among those given multiple hormone-blocking agents. Surgical removal of the testes was associated with a 40 percent increased risk for heart disease and a more than doubled risk for a heart attack.
"These drugs do have usefulness," Brawley said. But there has been debate about whether ADT should be used in some cases, such as when levels of prostate-specific antigen (PSA), a cancer-associated protein, begin to go up but there are no other signs and symptoms of cancer progression, he said.
"A man has had radical prostatectomy [cancer surgery] and PSA starts rising again," Brawley said. "There has been a debate in the medical profession: Should we start hormonal therapy or just watch it go up and act only if we see the cancer spreading?"
More research is needed to determine the proper course of action in these and other cases where the course of the disease is not clear, the new advisory said.
Meanwhile, "the American Cancer Society is advising that physicians be aware that all hormone therapies for prostate cancer can have an increased risk of cardiovascular disease and diabetes and death," Brawley said. "They can be useful in treatment but should be used with caution."
A need for caution was also emphasized by Dr. Arthur Sagalowsky, a professor of urology and chief of urologic oncology at the University of Texas Southwestern Medical Center in Dallas and one of two urologists representing the American Urological Association on the panel that produced the advisory.
"One needs to be very careful in not overdrawing conclusions beyond what the panel has done," Sagalowsky said.
The risk for cardiac problems should be one of many issues discussed in the treatment of prostate cancer, he said. "It adds to the body of information that I present to patients with prostate cancer when they decide whether or if to begin androgen-deprivation therapy," he said. "How one decides will depend on the circumstances of the patient's prostate cancer, and this individual side effect is one of the issues that enter into the discussion."
The U.S. National Cancer Institute has more on prostate cancer.