About a third of men over age 40, and about half of men age 65 to 79, get regular blood tests for prostate specific antigen, or PSA.
Rising PSA levels are an early sign of prostate cancer, but the test gives a false cancer signal up to 80% of the time. Moreover, not all PSA-detected prostate cancers are dangerous.
"The common perception that PSA-based early detection of prostate cancer saves lives is simply not supported by the scientific evidence," task force co-vice chair Michael L. LeFevre, MD, MSPH, professor of family and community medicine at the University of Missouri, tells WebMD.
The task force's draft statement, leaked to the press a week early, will be open for public comment next week before becoming the official recommendation of the U.S. government's top expert guideline panel.
The statement already is drawing harsh criticism, particularly from the American Urological Association.
"It is our feeling that, when interpreted appropriately, the PSA test provides important information," AUA President Sushil S. Lacy, MD, says in a news release. "Until there is a better widespread test for this potentially devastating disease, the [task force] -- by disparaging the test -- is doing a great disservice to the men worldwide who may benefit from the PSA test."
Criticism also comes from biostatistics expert Ruth Etzioni, PhD, of the Fred Hutchinson Research Center. Etzioni has served on prostate-cancer screening guidelines panels of the AUA, the American Cancer Society, and the National Comprehensive Cancer Network.
"The task force is oversimplifying a complex series of [clinical trial] results," Etzioni tells WebMD. "I think there is real evidence of benefit for PSA screening. Death rates from prostate cancer have gone down … It is hard for me to believe all that is due to better treatment." But Len Lichtenfeld, MD, deputy chief medical officer for the American Cancer Society, says the proposed guidelines reflect the hard reality that PSA testing does not appear to save lives.