The “digital examination” for prostate cancer is, well, unpleasant, and many men have hoped that the PSA blood test would someday eliminate the need for a doctor’s rectal examination. Unfortunately, recent results from two large studies show that the PSA test still has a long way to go.
The PSA test is routinely administered to millions of men each year in hopes of finding cancer in its early stages before it has enlarged the prostate gland enough for a doctor’s physical examination to detect its presence. The test looks for chemicals in the blood that may be a reaction to cancer in the prostate. While the test has been used and refined for more than two decades, it remains controversial because it returns a large number of results that indicate the possible presence of cancer but prove false after a biopsy is performed.
The problem is that no one knows what level of prostate-specific antigen actually indicates the presence of cancer in a particular individual. Generally, anything in the range of 7.0 to 9.0 ng/ml invites suspicion, and some doctors order biopsies at levels as low as 2.5 ng/ml. The biopsies can be painful and, in rare cases, can cause serious complications.
Test proponents argue that, despite the downside, the risk is worthwhile because early detection can spur early treatment. However, despite its status as the second-leading cancer killer of men in the United States, prostate cancer is very slow-developing. As a result, older men who are diagnosed are often advised to put off treatment and end up dying of something else first. Even in younger men, despite detection, monitoring rather than treatment is often ordered, due to the difficulties of treatment. Surgery, radiation and hormone treatments are often unsatisfactory, leaving patients incontinent, impotent and/or experiencing other debilitating complications.
The newest studies – one of 76,000 American men and the other involving 162,000 Europeans – add weight to those who see the tests as costly and unnecessarily unsettling. Utilizing investigations of large size and duration, each study found little evidence of fewer deaths among men who were given the PSA test. After ten years of testing, the American study showed no difference in fatalities between those who had regular PSA tests and those who did not. The European study, after ten years, showed an average of seven more lives saved for every 10,000 men tested, but these savings came on the basis of 336 additional treatments. In many of those cases, even without treatment, the patient might have survived to die of a different cause, and the study does not indicate how many of those who endured treatment suffered serious side effects.
“It’s very disturbing,” said one of the studies leaders, Fritz H. Schroder of the Erasmus Medical Center in the Netherlands, speaking to a Washington Post reporter. “That means, in order to save one life, you treat a very large number of men.”
The results raise the quandary for men and their doctors: if the tests have little promise of saving lives, are they worth taking?
For men with family members who have died from the disease, PSA testing makes sense, as almost any family physician would recommend. However, for those with no history, the test result may create anxiety, provoke a biopsy and invite further treatment while providing no more protection against death from prostate cancer than is afforded by the annual digital exam.
Meanwhile, research continues on other prostate test options which may one day prove more reliable than PSA testing. For a preview of these possibilities, read this report from the Brady Urological Institute at Johns Hopkins University.
June is Men’s Health Month. If you have not had a physical examination within the past two years, this may be a good time to schedule one. If you or your family members have questions about screening for prostate cancer, or any other conditions, you should contact your medical provider. For more information on prostate cancer, go to www.cancer.gov/prostate.