PSA Tests for Prostate Cancer May Not Save Lives
Study Shows Routine PSA Tests Don't Cut Deaths; First Test at Age 60 May Be Best for Most
Sept. 14, 2010 - Routine PSA screening tests for prostate cancer don't save lives.
That's the bottom line from a painstaking analysis of major clinical trials by University of Florida researcher Philipp Dahm, MD, and colleagues. They reviewed data on 387,286 men enrolled in six large clinical trials.
"We found no evidence to support the notion that prostate cancer screening improves overall survival or prostate cancer survival," Dahm tells WebMD. "It clearly increases the number of men diagnosed with prostate cancer. But based on high-quality evidence, there does not appear to be an impact on these two important outcomes."
Most U.S. men start getting PSA tests at about age 40. That's a good idea for men at high risk of prostate cancer: African-American men and men with a father, brother, or son who had prostate cancer before age 65.
Routine screening does, indeed, increase a man's chances of a prostate cancer diagnosis. For every 1,000 men screened, Dahm and colleagues find, 20 more cancers are diagnosed than in similar men who are not screened.
Nearly all of these cancers are early-stage cancers. But detecting these slow-growing cancers -- most of which will not be life threatening -- does not save lives.
Overdiagnosis of prostate cancer can lead to unnecessary treatments, including surgeries and radiation therapies that can leave men incontinent and/or impotent. Does this mean that routine PSA testing does more harm than good? Oddly enough, Dahm says, there's not enough study data to answer this question.
"Men diagnosed with prostate cancer typically get treated -- and we know there is a significant impact on quality of life: urinary function, erectile function, and so on. But none of these screening studies are comprehensive enough to look at what happens downstream to these patients," he says.
If saving lives is the point of routine PSA testing, the benefit is "not so great," says Gerald L. Andriole, MD, chief of urologic surgery at Washington University in St. Louis. Andriole's editorial accompanies the Dahm team's report in the Sept. 14 online issue of BMJ.
"When we do routine mass screening for prostate cancer there are winners and losers," Andriole tells WebMD. "Some men clearly benefit from early detection and early treatment. But other men are losers. They are diagnosed with a cancer, undergo unnecessary treatment and have side effects, and they go through all pain and anxiety associated with having cancer."