AAFP, USPSTF Issue Final Recommendation Against Routine PSA-based Screening for Prostate Cancer

Evidence Simply Does Not Support Test's Benefit, Says Task Force Co-chair

May 22, 2012 04:00 pm Matt Brown

The AAFP is recommending against performing prostate-specific antigen (PSA)-based screening for prostate cancer in asymptomatic men, a position that is in line with a final recommendation(www.annals.org) from the U.S. Preventive Services Task Force (USPSTF) that was published May 22 in the Annals of Internal Medicine.

[Breaking News]

The recommendation applies to asymptomatic men in the general U.S. population, regardless of age, but does not include the use of the PSA test for surveillance after diagnosis or treatment of prostate cancer.

According to USPSTF Co-vice Chair Michael LeFevre, M.D., M.S.P.H., a family physician from Columbia, Mo., it all comes down to the numbers. More than 300,000 men have been enrolled in randomized screening trials in nine countries, he told AAFP News Now, and, after 10 years of follow-up, "the hoped-for benefit is not apparent."

Doug Campos-Outcalt, M.D., M.P.A., of Phoenix, the Academy's liaison to the USPSTF, said that although he knows the report will cause controversy, the evidence against using the PSA screening test in asymptomatic men is clear.

"The simple fact is that most men who are found positive for prostate cancer through screening are not really benefitted by it at all, because the tumors are not aggressive," said Campos-Outcalt. "But oftentimes, these patients go on to receive treatments as if they were battling aggressive disease."

story highlights

  • The AFFP, in conjunction with the U.S. Preventive Services Task Force (USPSTF), has issued a final recommendation against prostate-specific antigen (PSA)-based screening for prostate cancer in asymptomatic men because evidence indicates that the harms of the test outweigh its benefits.
  • Ninety percent of U.S. men with PSA-detected prostate cancer are treated, and as many as five in 1,000 men who are treated surgically will die within one month of the surgery.
  • The PSA test often produces false-positive results, which are associated with negative psychological effects and other adverse events.
  • Some subspecialist groups are questioning the task force's interpretation of the data and calling for subspecialty representation on the USPSTF.

According to the USPSTF recommendation statement(www.uspreventiveservicestaskforce.org), evidence shows that nearly 90 percent of U.S. men with PSA-detected prostate cancer are treated with surgery, radiation or androgen deprivation. As many as five in 1,000 men who are treated surgically will die within one month of the procedure and between 10 and 70 of these men will have serious complications from surgery. In addition, of men treated with radiotherapy or surgery, 200-300 in 1,000 will suffer long-term problems, including urinary incontinence, impotence or both.

Moreover, said the statement, PSA testing often produces false-positive results (about 80 percent of PSA test results are false-positive when a PSA threshold between 2.5 micrograms per liter and 4.0 micrograms per liter is used). Such results are associated with negative psychological effects, as well as additional, unnecessary testing.

Taking this and other issues into account, the USPSTF stuck by its Oct. 7 draft recommendation, giving the guidance a D recommendation(www.uspreventiveservicestaskforce.org) despite requests by some commenters to temper that stance.

"A grade D recommendation means that the USPSTF has concluded that there is at least moderate certainty that the harms of doing the intervention equal or outweigh the benefits in the target population, whereas a grade C recommendation means that … there is at least moderate certainty that the overall net benefit of the service is small," the task force wrote in response to public comments it received on the draft recommendation. "The USPSTF could not assign a grade C recommendation for PSA screening because it did not conclude that the benefits outweigh the harms."

By no means, however, does a D recommendation preclude discussions between physicians and patients "to promote informed decision-making that supports personal values and preferences," the task force noted.

AAFP President Glen Stream, M.D., M.B.I., of Spokane, Wash., said that because the Academy takes such an active role in the USPSTF process, supporting the final recommendations becomes much easier. He said he hopes that in time, both physicians and the public will come to understand that despite having become a routine part of practice, the PSA-based test was doing far more harm than good.

"As an Academy, and as family physicians, our goal is to provide the best evidence-based medical care possible," said Stream. "The evidence is there, so we need to change practice based on that.

"When it comes down to individual doctors and their individual patients, they may still do the testing, but it needs to be done using all the information available. Having that discussion, and knowing the test may do more harm than good, is important."

LeFevre heartily agreed. "If a physician doesn't take the time to learn about the small -- at best -- expected benefit and the significant risk of harms of PSA screening and immediately turn around and have that conversation with the patient, then the physician should not order the test," he said. "Each offer should come with an open and honest discussion, and we are clear about that in the final recommendation."

But although the task force and its supporters(www.annals.org) are convinced that routine PSA testing is not good medical practice, others, including the American Urological Association (AUA), offer a different view. In an article(www.annals.org) published in the same issue of Annals, an ad hoc group of physicians contends that the USPSTF, which it termed "a panel that does not include urologists or cancer specialists," underestimated the benefits and overestimated the harms of prostate cancer screening, pushing the group to disagree with the task force's recommendation.

"At this point, we suggest that physicians review the evidence, follow the continuing dialogue closely and individualize prostate cancer screening decisions on the basis of informed patient preferences," the authors wrote.

In fact, a resolution to this effect(www.ama-assn.org) has been submitted for consideration during the 2012 annual meeting of the AMA House of Delegates. Specifically, the measure (Res. 506) calls for the AMA to "encourage proportional representation of specialists" in the USPSTF.

Campos-Outcalt said such arguments lack merit.

"The fact that no urologist is on the panel is irrelevant, as the data are what the data are," he said. "The task force sent out its draft recommendations to the specific organizations, as well as the public at large, for comment and considered every scientifically based objection because the task force is evidence-driven.

"The meat of (these groups') argument is a different interpretation of the multiple studies involved that uses relative risk reduction and not absolute risk reduction, which is much less impressive, and that does not quantify the harms -- including deaths that can occur from the treatments. It also uses the time trend data on prostate cancer mortality, which is very low-level evidence."

In response to the release of the draft USPSTF recommendation last October, the AUA said in a statement(www.auanet.org) that it was in the process of developing a new clinical guideline for prostate cancer screening and that its expert panel would review use of the PSA test in the context of early detection of prostate cancer overall.

Stream said it is his hope that, because the USPSTF has determined that PSA screening does more harm than good, the medical establishment will be inspired to identify a better test.

"I think a lot of what drives physicians to continue offering the PSA is the idea that some test is better than none," he said. "Men and their doctors are concerned about prostate cancer, screening for it and treating it in a way that leads to a good quality of life, but it appears that the current PSA is not that test."