WEDNESDAY, Jan. 12, 2005 (HealthDayNews) -- Hormone therapy has its drawbacks for men as well.
A new study has found that older men receiving androgen-deprivation therapy for prostate cancer, an increasingly common treatment for a common cancer, showed an increased risk of bone fracture.
That risk increased with the number of doses given, according to the study, which appears in the Jan. 13 issue of the New England Journal of Medicine.
The finding raises the question of whether anything should be done to counteract the therapy's negative effect.
"The drugs have the appearance of being relatively benign, and we're trying to say think about it, for both physicians and patients, that there is a risk to this therapy and that at least should be incorporated into a discussion," said study author Dr. Vahakn Shahinian, an assistant professor of internal medicine at the University of Texas Medical Branch, Galveston.
"The urologic community is already aware of the fact that androgen-deprivation therapy has a certain number of side effects, including osteoporosis and possible fracture," added Dr. Nelson Neal Stone, a clinical professor of urology and radiation oncology at Mount Sinai School of Medicine in New York City. "The issue of fracture has been talked about, but there are no guidelines on whether or not men should be started on any preventive medication."
This type of hormone therapy works in the opposite way as hormone therapy does for women. In women, hormones are added whereas, in men, measures are taken to reduce the level of male hormones (called androgens, such as testosterone) in the body.
"The idea behind it is that prostate cancer cells are responsive to male sex hormones like testosterone, so if you can shut down testosterone in the body, either through surgical castration or medication, you can slow the growth of the prostate cancer," Shahinian explained. "Primarily, it has been used in patients who have metastatic disease and as a means not to cure the cancer, but rather to slow it down, shrink the cancer cells a little bit, alleviate some of pain and problems that come about because of the spread of the cancer."
The drugs have also been shown to prolong life when used in combination with radiation in people with locally advanced cancer.
Over the past 15 years, however, androgen-deprivation therapy has been increasingly used and used with other therapies in earlier stages of cancer, where the evidence is less clear.
"There's a degree of uncertainty here," Shahinian said. "A lot of patients are getting therapy in that sort of gray zone."
While experts have known that androgen-deprivation therapy is associated with a loss of bone mineral density, its effect on fractures has been less clear.
To clarify this, Shahinian and his colleagues analyzed the medical records of 50,613 men aged 66 and over, who are listed in the linked database of the Surveillance, Epidemiology, and End Results program and Medicare and who had been diagnosed with prostate cancer between 1992 and 1997.
Among the men who had survived at least five years from the date of their diagnosis, 19.4 percent of those who received hormone therapy had a fracture compared to 12.6 percent of those who didn't.
Those patients who were given at least nine doses in the year after their diagnosis were 45 percent more likely to suffer a bone fracture than were those who did not receive the treatments. They also had a 66 percent greater risk of having a fracture that required hospitalization.
Given that 220,000 men are diagnosed with prostate cancer each year and that more than 40 percent of those receive androgen-deprivation treatment, this translates into approximately 3,000 fractures each year attributable to this type of treatment, the authors stated.
The findings have several implications.
"We need to incorporate the knowledge of these risks into the discussions that take place between patients and physicians about whether to indicate this therapy in situations where we dont know whether or not it's going to help them," Shahinian said.
Then, men who decide to go ahead with the therapy should have their bone mineral density monitored, and possibly take protective drugs such as bisphosphonates, Shahinian said.
"We haven't proven that these bisphosphonates reduce fracture risk, but they do appear to protect bone mineral density and probably will protect against fracture," Shahinian added.
More information
The American Cancer Society has more on androgen-deprivation therapy.
