MONDAY, Sept. 28 (HealthDay News) -- Most men are not being told the pros and cons of PSA tests, two new studies find.
Although PSA tests can detect prostate cancer, they can't predict which cancers are aggressive and which are so slow-growing that they don't need to be treated. This leads to overtreatment, which can have immediate consequences, such as impotence and incontinence, and only a tiny increase in survival, researchers say.
"Men in the United States have not been adequately told about the questions regarding the efficacy of prostate cancer screening," said Dr. Otis W. Brawley, chief medical officer at the American Cancer Society, who was not involved in either study.
"They have been misled and over-promised," he said. "People have replaced the hope that prostate cancer screening is beneficial with the message that it is definitely beneficial."
The reports are published in the Sept. 28 issue of the Archives of Internal Medicine.
In the first study, a team led by Dr. Richard M. Hoffman, from the New Mexico VA Health Care System, collected data on 3,010 men 40 and older reached by telephone. Among these men, 375 had undergone or discussed PSA screening in the past two years.
In all, 69.9 percent of the men had discussed screening with their doctor before making a decision. Of these men, 14.4 percent chose not to have the test. In most cases the doctor brought up having the test (64.6 percent), with 73.4 percent recommending it, which was the only point of the discussion, the researchers said.
"Thirty percent of the men said it wasn't even discussed at all," Hoffman said. "Men who did discuss screening heard about the benefits of screening; very few heard about the side effects of screening."
In addition, most men didn't know a lot about prostate cancer, Hoffman said. In fact, only 47.8 percent of men correctly answered any of three questions about prostate cancer risk and screening, Hoffman said.
"This is a very important decision. We think it should be an informed or shared decision, and it's not happening," he said.
The problem with getting the test is that a positive result is going to lead to a biopsy, and only one out of four men who have a biopsy have cancer, Hoffman said.
One reason these discussions aren't taking place is that doctors don't have enough time to discuss screening and prostate cancer in general with their patients, Hoffman said.
Men should educate themselves about the pros and cons of PSA testing, Hoffman said. There are various aids for making such a decision both on the Internet and in print, he said.
In the second report, Kirsten Howard, a senior lecturer in health economics at the University of Sydney in Australia, and colleagues created a statistical model, based on family history, to provide information for men who have low, moderate and high risk for prostate cancer.
"The results of the model predict that benefits and harms of annual PSA screening vary with age and risk level," Howard said.
For example, screening 1,000 men every year from age 40 to 69 only reduces the number who will die from prostate cancer by age 85 from 30 to 28, Howard said.