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The debate over prostate cancer tests

It would seem all men should have PSA checks to detect cancer. But the medical community is divided. Some, even the scientist who discovered PSA, see more harm than good.

March 07, 2011|By Chris Woolston, Special to the Los Angeles Times
  • PSA levels can be checked with a blood test. Some doctors say the test does more harm than good.
PSA levels can be checked with a blood test. Some doctors say the test does… (Mark Boster / Los Angeles…)

Men of a certain age have heard the pitch many times: If they care about their health, they really should get their PSA checked. The simple blood test, men are told, can help uncover hidden cases of prostate cancer and potentially save their lives.

More than 20 million American men get their PSA measured each year. Doctors often include the test as a routine part of checkups for men older than 40, and many insurance companies flat-out require it. Cancer awareness campaigns frequently tout PSA tests as an important weapon against the disease, something like a male version of mammograms. The fact that prostate cancer kills more than 27,000 men a year may make the test seem like a no-brainer.

But when it comes to cancer screening, few things are as simple as they seem at first.

The PSA test is currently under attack on many fronts. While some experts credit the test with saving tens of thousands of lives each year, others say the benefits are over-hyped and might just be an illusion. And because treatments for prostate cancer can cause complications such as impotence and incontinence, there's a growing fear that PSA testing ends up harming far more men than it helps.

A quick primer: Adult prostate glands make prostate specific antigen, or PSA, a protein that helps make semen. Healthy prostates tend to release only a trickle of the protein into the bloodstream, but cancer generally turns up the flow. Men with a PSA of more than 4 nanograms per milliliter of blood or with PSA readings that jump more than 0.35 ng/mL from one year to the next are usually offered a needle biopsy to check the prostate for cancer.

The American Cancer Society advises men to make their own decision about the test after talking to their doctors. But even if doctors are up to speed on the latest PSA studies — which is hardly a given — they probably don't have time to discuss all the ins and outs of screening for prostate cancer, says Dr. Barnett Kramer, editor in chief of the Journal of the National Cancer Institute and an outspoken PSA skeptic.

"Men are left in the uncomfortable position of deciding whether to have a test where the benefits are uncertain but the harms, for many, are inescapable," he says.

Some men choose to skip the test. Richard Ablin of Tucson is 70 and has never had his PSA checked. Not once. And it's not because he's uninformed. Quite the opposite: He's the scientist who discovered PSA more than 40 years ago.

He doesn't want congratulations for the test he helped make possible; he just wants it to go away. In an essay published last year in the New York Times, Ablin, a research professor of immunobiology and pathology at the University of Arizona, called PSA testing a "hugely expensive public health disaster."

The test, he says, is inaccurate and misleading. Worse, it puts many man on a path toward invasive and life-changing treatments that they could easily have lived without. "We're spending $3 billion a year on a test that cannot detect cancer," he says. "I've been trying to put the kibosh on this for years."

In fact, nearly 20 years after PSA tests first came into wide use, experts are still wrestling with a seemingly simple question: Does it save lives?

A 2009 study that followed more than 76,000 American men ages 55 through 74 for 10 years was supposed to provide the answer. Half the men were offered yearly PSA tests and the other half received "usual care," which sometimes included the test. By the end of the study, 50 patients in the annual testing group had died of prostate cancer, compared with 44 patients in the usual care group. From a statistical point of view, screening didn't seem to make any difference.

The study, while imperfect, should have been able to detect any lifesaving benefits had they existed, says lead researcher Dr. Gerald Andriole, a professor of surgery at Washington University School of Medicine in St. Louis. Researchers are continuing to follow the men and plan to publish an update sometime this year.

A similar randomized study, also published in 2009, followed more than 160,000 European men ages 55 through 69 for an average of nine years. This time, there was a survival difference: Men who received annual PSA tests were 20% less likely to die of prostate cancer than those who weren't tested. A 2010 follow-up of this study that tracked more than 19,000 Swedish men for 14 years suggested that screening reduced cancer deaths by 44%.

Andriole sees a serious shortcoming in the European results: Unlike the American study, in which all patients with prostate cancer had access to roughly the same treatments, the Europeans who got the test also had better access to top-notch surgeons and aggressive hormone therapy than their untested peers. The treatment gap alone could largely explain why men who got the test were more likely to beat their disease, Andriole says.

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