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Studies Cast New Doubt on Prostate Cancer Screening

Recent studies show that screenings for prostate cancer may not reduce death rates and may also lead to unnecessary treatment. A medical researcher discusses the latest findings.

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  • RAY SUAREZ:

    Millions of men take a blood test annually to see if they have any indications of prostate cancer, but there have been growing questions about the value of the PSA test, as it's known.

    A pair of studies in the New England Journal of Medicine are adding more fuel to the controversy surrounding screening. Researchers in the U.S. and Europe independently followed a total of more than 250,000 men over a period of years. They found separately that the PSA test did not significantly reduce death rates.

    The European study also suggested that, in many cases, the blood tests may have led to unnecessary treatment.

    To help us understand more about the findings and questions, we're joined by Andrew Vickers. He specializes in prostate cancer research as a statistician at Memorial Sloan-Kettering Cancer Center in New York.

    And, Andrew Vickers, you had a large number of test suggests. You were able to follow them — or the researchers were — able to follow them for a long time in a large number of countries. So what were they trying to answer? And what did they find out?

  • ANDREW VICKERS, Memorial Sloan-Kettering Cancer Center:

    Well, there are two very different studies going on. There's the one, as you mentioned, in the U.S. and the one in Europe. And they're really quite different studies.

    The U.S. situation is really quite different, because a lot of men are out there and they're having PSA tests. And this was pretty much irrespective of what the researchers asked them to do. In the U.S. study, about half of the patients entering the study had already had a PSA test. And even those who were assigned to the control group, about a half of those continued to have PSA tests during the study.

    In Europe, it's really a very different situation. PSA testing hasn't become part of routine medical practice, and very few men have had a PSA test entering the trial and only a small proportion of those in the control group actually went ahead and had a PSA test during the trial.

    So they're really quite different trials, and I think that's reflected in their different results. The U.S. results didn't find an important difference between the men told to have PSA tests and the men who were recommended to avoid the PSA tests.

    In Europe, you did see a small, but statistically significant drop in mortality — about a 20 percent reduction in death from prostate cancer — in men advised to undergo the PSA test.