Saturday, May 26, 2012

Panel advises against PSA cancer screening

Doctors should no longer offer the PSA prostate cancer screening test to healthy men because they're more likely to be harmed by the blood draw � and the chain of medical interventions that often follows � than be helped, according to government advisory panel's final report.

Even after studying more than 250,000 men for more than a decade, researchers have never found the PSA to save lives, according to the U.S. Preventive Services Task Force, a panel of doctors that advises the government on cancer screenings and other ways to avoid disease.

Yet the PSA can cause harm.

That's because the PSA, which measures a protein called prostate-specific antigen, often leads to unnecessary needle biopsies for men who don't actually have cancer. Even worse, those biopsies lead many men to be treated for slow-growing cancers that never needed to be found and that are basically harmless, says task force chairwoman Virginia Moyer, a professor of pediatrics at Baylor College of Medicine in Houston.

Because doctors today often can't tell a harmless tumor from an aggressive one, they end up treating most men with prostate cancer the same, says Otis Brawley, chief medical officer of the American Cancer Society, which takes a neutral stand on the PSA.

Treating harmless prostate tumors can't possibly help men, however. It only increases the odds of making them impotent or incontinent, Moyer says. Treatment can even be deadly: One in 200 men who have prostate surgery die shortly after the procedure, she says.

The recommendation, first released as a draft in October, applies to healthy men of any age, although not for those who already have been diagnosed with prostate cancer.

The panel didn't consider cost in its deliberations, Moyer says. Federal legislation requires that Medicare must continue to pay for the PSA, Brawley says. Private insurers usually follow Medicare's example.

In the future, Moyer hopes doctors will simply stop mentioning the PSA when men come for office visits. If men ask for the test, or if doctors still want to offer the PSA, Moyer says she hopes physicians will discuss both the risks and benefits of screening. Although the task force aims to help doctors by issuing recommendations, physicians aren't obligated to follow its recommendations, Moyer says.

Yet Moyer agrees that men desperately need a better test. More than 28,000 men die of prostate cancer a year.

Unfortunately, there are no other better tests with which to replace the PSA, such as rectal exams, ultrasounds or variations on the PSA, says Ian Thompson, chairman of urology at the University of Texas Health Science Center at San Antonio and a spokesman for the American Urological Association, which recommends the PSA for men over 40. Thompson supports some of the task force's recommendations, such as its call to do away with mass prostate cancer screenings in shopping malls and parking lots.

But Thompson says the task force went too far in rejecting the PSA completely. He notes that death rates from prostate cancer nationwide have dropped 30% to 50% since PSA testing became widespread in the early 1990s. In its recommendations, published in Monday's Annals of Internal Medicine, the task force said it's unlikely that screening alone could have reduced death rates so quickly. Some experts note that treatments also have improved.

Thompson also says he doesn't want to go back to the "bad old days" before screening, when doctors found prostate cancer only after it had become incurable. And because many men are used to getting PSAs, Thompson says, some might not realize their doctors have stopped performing the tests.

"A patient might presume they've had their PSA tested, then come back five or 10 years later with back pain," only to learn they have prostate cancer that's spread to their spine, Thompson says.

Terry Dyroff, 66, says he first realized the risks of prostate screening five years ago. He developed a life-threatening bloodstream infection called sepsis after his PSA results led to a needle biopsy, and he was hospitalized for three days. Though such infections are rare, Dyroff says one such experience was enough; he hasn't had a PSA since. "At my age, if I developed prostate cancer, I'd rather not know," says Dyroff, of Silver Spring, Md. "And if I did know, I probably wouldn't do anything about it."

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