Prostate Cancer Screening Does Not Save Lives
This topic has received attention on this blog before (find the most recent entry on this topic here) but needs reiteration. More medical testing is not always better quality care. The Washington Post (find it here) reports that the results of a recent multi-year study of the PSA test, used for detecting prostate cancer early, have been published. Excerpts:
Find prostate cancer early, save a life.
That message has been pervasive since 1986, when a blood test for prostate cancer first hit the market. But more evidence suggests that, in many or even most cases, the message is wrong.
Launched in 1993, the National Cancer Institute-funded study followed 76,000 men at 10 sites nationwide for about 13 years. Half received annual PSA tests for six years and also received digital rectal exams, which can help detect some prostate tumors. The other half, in the “community care” group, continued under the care of their regular doctors. Although doctors found about 12 percent more cancers in the PSA screening group, both groups had about equal numbers of deaths. Detecting the extra cancers, in other words, did not reduce the death rate from the disease.
“There is a tendency to believe that if a test finds disease, that must be a good thing,” saidOtis Webb Brawley, a cancer screening expert and chief medical officer of the American Cancer Society. But that isn’t necessarily so, he said, adding, “I’m very worried about ‘auditorium medicine,’ where a long line of guys waits to get screened and there is no discussion or education about the potential risks and benefits.”
Ideally, none of the men in the “community care” group would have received PSA testing. That would have made the study a clearer test of whether the screening saves lives. But in the 1990s, primary care physicians rapidly adopted routine screening in men 50 and older. About half of the men in the “community care” group did, in fact, receive PSA testing.
That factor muddied the results, said Jonathan W. Simons, an oncologist and chief executive of the Prostate Cancer Foundation, a patient advocacy group. “The study is so fundamentally flawed it doesn’t move us forward in what we need to do to reduce deaths from prostate cancer.”
But the NCI has never recommended routine screening. And the American Cancer Society counsels men older than 50 to discuss the test with their doctors.
In October, a national debate erupted after an influential government panel concluded that most men should not be routinely tested. Screening does not save lives, the U.S. Preventive Services Task Force found in its draft recommendation, but instead encourages unnecessary treatment.
Still, the new results had some testing proponents softening their message. “Maybe we don’t need to do PSA [tests] every year,” said Andrew K. Lee, an oncologist at the M.D. Anderson Cancer Center in Houston. “Maybe we can initially do a few PSA [tests] as a baseline and then do them every couple years.”
Study leader Andriole said African American men, who are at higher risk of dying from the disease, and men with a family history of prostate cancer are most likely to benefit from regular screening.
Brawley said that men age 50 and up should talk with their doctors about the testing. “This is a lot more complicated than ‘just get the test,’ ” he said.
Simons said that while the benefits of regular PSA testing remain uncertain, one thing is clear: “We need a better test than PSA.”
Just because a test can be done, does not mean it should be done. Nor does it mean that communal taxes or premiums should be used to pay for the test. Part of the controversy related to this newly published study is that use of the PSA test on a widespread basis became common before the value of the test could be carefully examined. Thus, finding a group of men who have not been tested is now impossible. I know this from personal experience. My doctor has energetically argued that I should have the test done, even without data proving that undergoing the test will actually lessen my risk of death due to prostate cancer. My spouse chimed in urging me to undergo PSA screening because a good friend of about my age recently had PSA testing, received a diagnosis of prostate cancer, and is under treatment. I caved in to the pressure.
The best use of our limited resources for health care, however, would be to have a mechanism for communal designation of clinically useful medical and surgical interventions. People, on an individual basis, would be able to purchase whatever health care goods and services their pocketbook can afford. As a community, however, we should limit our clinical purchases to those interventions that are backed by medical science.
The PSA test may fit those criteria for high risk populations, such as African American men. The general population, however, does not have an advantage from mass screening with PSA.
Dr. Joe Jarvis