May 22, 2012
Expert Medical Panel Urges Doctors To Stop PSA Cancer Screenings
An expert US medical panel has given its final word on the PSA test, a controversial screening procedure used to detect prostate cancer in men, recommending that doctors should no longer perform the test on healthy men because they are more likely to be harmed by the test itself than be helped.
The US Preventive Services Task Force (USPSTF) gave its recommendation on the stoppage of the PSA (prostate-specific antigen) test following a public comment period. It gave the test a D rating -- meaning that physicians should not offer the test because the harms outweigh the benefits.
Even after studying more than 250,000 men for more than a decade, the task force found the test likely only saves 1 life for every 1,000 men screened. They also determined that many men will get suspicious results when there is in fact no cancer at all, triggering unneeded biopsies that pose potential complications such as pain, fever, bleeding, infection and hospitalization. And even in the event cancer is detected, as much as 90 percent receive surgery or radiation even though most tumors are not life-threatening.
The task force´s new recommendations are being published in the online issue of Annals of Internal Medicine. The last time the agency gave a recommendation on prostate cancer screening (2008), it concluded there was no evidence to support PSA testing for men over the age of 75.
“There is convincing evidence that the number of men who avoid dying of prostate cancer because of screening after 10 to 14 years is, at best, very small,” wrote the panel.
For every 1,000 screened men, as many as 40 will suffer impotence or urinary incontinence as a side effect of treatment, two will have heart attacks or strokes and one will develop a dangerous blood clot in the legs or lungs, and as many as five of 1,000 men who undergo surgery will die within a month, said the task force in its report, after a review of scientific findings.
“There is a small potential benefit and a significant known harm,” said Dr. Virginia A. Moyer, a professor of pediatrics at Baylor College of Medicine in Houston, and chairwoman of the task force. The PSA test “should not be part of your checkup.”
Task force member Dr. Michael LeFevre, of the University of Missouri in Columbia, said that instead of the PSA test, men who want to protect their health should talk with their doctors about prostate health problems. A digital rectal exam is a better option than the PSA test, he added, although there is not much support for that exam either.
Ian Thompson, chairman of urology at the University of Texas Health Science Center at San Antonio and a spokesman for the American Urological Association, said he still recommends the PSA test form men over 40. However, he does agree with some of the task force´s recommendations, such as the call to do away with mass screenings in shopping malls and parking lots.
But, he said, the task force has gone too far in rejecting the PSA screenings completely. He noted that death rates from prostate cancer nationwide have dropped 30 to 50 percent since PSA screenings became widespread in the early 1990s.
The task force said, however, that is highly unlikely that screening alone could have reduced death rates so quickly.
Thompson also said he doesn´t want to return to the days before PSA screening was around, when doctors found prostate cancer only after it had become incurable.
The task force has underestimated the benefits and overestimated the harms of prostate cancer screening, added William J. Catalona, M.D., Medical Director of the Urological Research Foundation and author of an accompanying editorial. He and his colleagues argue that the task force -- whose panel does not include urologists or cancer specialists -- largely based its recommendations on flawed studies with inadequate follow up time. The recommendations also focused on mortality and did not take into consideration the substantial illness related to living with advanced cancer, he remarked.
Dr. Henry Lynch, Director of the Hereditary Cancer Center at Creighton University, and coauthor of the editorial, added that the recommendations also leave out high-risk populations and younger men.
“The recommendations of the USPSTF carry considerable weight with Medicare and other third-party insurers,” Dr. Lynch said. “My colleagues and I strongly believe that the Task Force recommendations should not be used as justification by insurers, including Medicare, to deny diagnosis of prostate cancer to the male population at risk.”
However, overdiagnosis makes screening seem to save lives when it truly does not, said Otis W. Brawley, M.D., MPH, Chief Medical Officer of the American Cancer Society, and author of a second accompanying commentary. Many men are diagnosed with prostate cancer that may never have progressed within their lifetime. Yet because they were screened and treated, they think screening saved their lives.
“Many people have a blind faith in early detection of cancer and subsequent aggressive medical intervention whenever cancer is found,” wrote Dr. Brawley. “There is little appreciation of the harms that screening and medical interventions can cause.”
Many of those who commented on the recommendations urged the task force to change the recommendations from a grade “D” to a grade “C” -- meaning physicians could provide the test to patients who request it. However, no new evidence was presented, and the recommendation remains unchanged.
While the task force only recommends that doctors should not offer PSA screenings, it said that the option to do so is still entirely up to healthcare providers.
“The USPSTF recognizes that clinical, policy, and coverage decisions involve more considerations than evidence alone,” said Moyer. “Clinicians and health care providers should understand the evidence but individualize decision-making to the specific patient or situation.”