Benefits of PSA Test Are Exaggerated

Risks of unnecessary procedures, and suffering, mean men should proceed with their eyes open.

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Otis Brawley, a professor of hematology, oncology, medicine, and epidemiology, is chief medical officer of the American Cancer Society.

I should start by saying that I am not against prostate cancer screening but am for informed decision making between patients and their physicians.

Prostate cancer is a devastating disease that causes more than 30,000 deaths every year in the United States. We desperately need effective measures to control it. The question is, do we currently have effective measures? Is the PSA test the best weapon against it?

I am concerned that the benefits of prostate cancer screening are frequently exaggerated when men are encouraged to get screened but the limitations of screening are not mentioned. I would like to see every man make an informed decision about what is right for him personally after hearing a balanced presentation of the potential benefits and risks of screening.

All of us in the medical and advocacy communities should respect that choice. Some men who are especially concerned about prostate cancer may reasonably choose to be screened. This is appropriate for them and should be encouraged. Some men may choose not to be screened; this is appropriate for them, and they should be supported in this decision and not criticized. Indeed, most American and European medical organizations with expertise in prostate cancer screening do not recommend for or against it but instead recommend informed decision making.

We often hear simple messages used to convey very complex issues, and that is an ethical concern for me. Advocates often encourage screening with messages that are so simple they are misleading—for example, "Screening definitely saves lives," or "Only a fool would not get screened for prostate cancer."

One can reasonably be a proponent of prostate cancer screening at this time without such exaggerations. It is fair and appropriate to say that screening may save lives. It is fair and appropriate for a survivor to say, "I believe prostate cancer screening saved my life." The problem is that there is not conclusive evidence at this time that prostate cancer screening saves lives.

In the science of screening, the gold standard in determining whether a screening test is beneficial is not a study to see if it finds early disease or extends survival. It is a prospective randomized trial of a group screened compared with a group not screened in order to look at death rates in the two groups over time. There is a published randomized trial of prostate cancer screening that found a 20 percent reduction in risk of death.

What you may not have heard is that means a man's risk of dying from prostate cancer went from 3 in 100 to 2.4 in 100, and 48 men had to be treated for each life saved. Many had significant side effects, such as urinary incontinence and impotence, that will last the remainder of their lives. There is a similar randomized trial that did not find a benefit in terms of lives saved but did find that screening causes a lot of additional diagnoses and unnecessary treatments, which lead to unnecessary side effects and other consequences.

I often talk to groups of doctors about screening and ask this theoretical question: If I had a pill that had no side effects but over time doubled my lifetime risk of being diagnosed with prostate cancer, but also might lower my risk of prostate cancer death by 20 percent, from 3 percent lifetime risk to 2.4 percent, should I take this pill? Rarely does anyone express interest in taking it.

Many doctors are shocked that a number of clinical trials and epidemiologic studies of prostate cancer screening outcomes in the United States over the past two decades demonstrate that this is the outlook for a man who chooses routine annual screening with the PSA test.

Indeed, many in the medical profession need more education about prostate cancer screening. One of many reasons why there are not better tests to predict the cancers that need treatment versus the cancers that do not is a failure of physicians to grasp the need for such a test. Complacency with a less-than-adequate test has kept us from improving screening and care for our patients. It is my belief that until we have better tests, a man can reasonably choose to be screened for prostate cancer, or reasonably choose not to be screened.