According to the findings, there was a 10 percent increase in the risk of death with intermittent therapy. Average survival was 5.8 years for the continuous group and 5.1 years for the intermittent group.
But the study called the findings "statistically inconclusive" for figuring out which treatment helps men live longer. And men who took the intermittent treatment did report better quality of life and mental health three months into the study, but not afterward.
Hussain said continuous treatment should remain the standard if the focus is on extending life. But those worried about side effects could still consider the intermittent treatment, she added.
The study, which didn't examine how much each kind of treatment costs, appears in the April 4 issue of The New England Journal of Medicine.
Dr. Bruce Roth, a professor of medicine in the division of oncology at Washington University in St. Louis, said the standard of care should probably remain the continuous approach. Some doctors are currently experimenting with the intermittent approach, he said, although there has been a shortage of high-quality research to support it.
The good news, he said, is that physicians are moving closer to turning prostate cancer into a chronic yet treatable disease, like high blood pressure and diabetes.
For more on prostate cancer, try the U.S. National Library of Medicine.
SOURCES: Maha Hussain, M.D., professor of medicine and urology, associate director for clinical research and co-leader, Prostate Cancer Program, University of Michigan Comprehensive Cancer Center, Ann Arbor; Bruce Roth, M.D., professor of medicine
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