PSA screening: What doctors tell their patients
The editors of Perspectives polled 15 Harvard-affiliated physicians — a decidedly unscientific survey — to find out what they tell patients about prostate-specific antigen (PSA) screening. Most of those polled are internists, the medical practitioners most likely to have a discussion with a patient about the risks and potential benefits of PSA screening. Interestingly, the findings from the American Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial and the European Randomized Study of Screening for Prostate Cancer (ERSPC) did nothing to change their recommendations: without exception, what they tell patients now is no different from what they told patients before the studies were published at the end of March. A representative sample of replies follows.
"Since many prostate cancers are slow-growing and never spread, and since treatments for prostate cancer have side effects, to have value a screening test must be shown to reduce a patient's risk of suffering (both from the disease and from treatment side effects) and risk of death. This has not yet been shown for the PSA test, based on these two long-awaited recent studies. Until and unless it is, I won't routinely screen the average man (without any risk factors for prostate cancer) with PSA testing. But since I don't think it's been conclusively shown that PSA testing does not reduce a patient's risk of suffering, I will obtain the test if a patient wants it, after hearing my assessment of the evidence."
— Anthony L. Komaroff, M.D.
"The ERSPC and PLCO trials finally give us some quantitative sense of the trade-offs between the benefits and harms of PSA screening. Men in the United States have about a 3% risk of eventually dying of prostate cancer. At best, if the ERSPC estimate is correct, and not the result of chance or bias, a man who chooses regular screening could lower that risk by about 20%, or to about 2.4%. However, he'd raise his risk of having to eventually face a diagnosis of prostate cancer by 70%, or from about 10% to 17%. More aggressive screening strategies than the ERSPC (annual screening, using lower PSA thresholds to recommend biopsy, using PSA velocity in addition to the PSA level) would drive the risk of eventually facing a diagnosis of prostate cancer even higher, for uncertain benefits.