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Our Year in Review series highlights the major medical news stories of 2012. One of the year's controversies centered on the United States Preventive Services Task Force recommendation against PSA screening for prostate cancer in otherwise healthy men. Here is the original story, published on May 21. In a companion article, you'll find out what has happened since then.

Healthy men should no longer have PSA measurements as a screening test for prostate cancer, according to a final recommendation from the United States Preventive Services Task Force (USPSTF).

The so-called grade D recommendation applies to men of all ages, but does not apply to the use of PSA testing for monitoring patients after a prostate cancer diagnosis or treatment.

Calling prevention of prostate cancer deaths the primary goal of screening, the task force cited a lack of evidence that PSA testing has an impact on that goal.

"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," members of the task force said in an article published online in Annals of Internal Medicine. "There is adequate evidence that the benefit of PSA screening and early treatment ranges from 0 to 1 prostate cancer deaths avoided per 1,000 men screened."

On the other hand, convincing evidence of potential harms related to PSA testing does exist. Psychological harm occurs almost immediately when men receive a false-positive test result (estimated to account for 80% of all positive PSA tests when cutoff values of 2.5 to 4.0 µg/L are used).

"Men who have a false-positive test result are more likely to have additional testing, including one or more biopsies, in the following year than those who have a negative test," the task force panel wrote. "Over 10 years, approximately 15% to 20% of men will have a PSA test result that triggers a biopsy, depending on the PSA threshold and testing interval used."

Data from a recent randomized trial showed that a third of men who have PSA-prompted prostate biopsies have pain, fever, bleeding, infection, transient urinary problems, and other issues that require physician follow-up. About 1% of prostate biopsies cause adverse events that result in hospitalization, according to the USPSTF panel.

The comments and conclusions came as no surprise. The USPSTF recommended against PSA testing as a prostate cancer screening tool in a draft guideline released in the fall of 2011.

Despite its position against PSA screening, the panel acknowledged that some men will still want the test and some physicians will continue to offer it.

"The decision to initiate or continue PSA screening should reflect an explicit understanding of the possible benefits and harms and respect the patients' preferences," the panel wrote.

The recommendation drew quick responses, two of which appeared as commentaries that accompanied the journal article. In one of the commentaries, the co-authors began by noting that the task force panel that made the recommendation included no urologists or cancer specialists.

"We, an ad hoc group that includes nationally recognized experts in the surgical and radiological treatment of prostate cancer, oncologists, preventive medicine specialists, and primary care physicians, believe that the USPSTF has underestimated the benefits and overestimated the harms of prostate cancer screening," Marc Rendell, MD, of Creighton University in Omaha, Neb., and co-authors wrote in their introduction.

The USPSTF based its recommendation largely on data from two large trials of PSA screening for prostate cancer. One trial showed no difference in prostate cancer mortality between screened and unscreened men. The other showed an adjusted reduction in mortality risk of 29% among screened men, which the USPSTF translated into too few lives saved to offset the potential harms of screening.

Rendell and co-authors cited what they considered several flaws in the USPSTF recommendation and the process that led to the recommendation:

• Failure to consider that procedures and associated complications occur in unscreened patients
• Focusing on mortality and ignoring the illness associated with living with cancer
• Inadequate consideration of potential benefits in high-risk populations
• Failure to consider epidemiologic data showing a 40% reduction in prostate cancer mortality and 75% reduction in diagnosis of late-stage prostate cancer since the introduction of PSA testing
• Applying the recommendation without regard to age could increase the number of advanced cancers at diagnosis

Noting the potential economic implications of the task force recommendations, Rendell and co-authors wrote, "We believe that elimination of reimbursement for PSA testing would take us back to an era when prostate cancer was often discovered at advanced and incurable stages."

The American Cancer Society (ACS) also weighed in on the issue, and generally supported the USPSTF decision.

"It is my hope that the current USPSTF recommendation ends mass screening," ACS scientific officer Otis Brawley, MD, wrote in another commentary published along with the recommendation. "Although recommending against routine screening, the Task Force does leave room for it within the physician-patient relationship."

"We must heed science when making clinical and policy decisions about PSA-based prostate cancer screening," Brawley added. "The harms are well-proven, whereas the evidence of benefit is weak. Even if one accepts that true benefits exist, the documented harms are likely greater than those small benefits."

"Despite this, some will continue to forcefully advocate PSA-based screening because of a blind faith in early detection. We need to practice medicine on the basis of evidence and not on the basis of faith," he said.

The American Urological Association (AUA) also responded. At the group's annual meeting in Atlanta, AUA vice chair of the health policy council David Penson, MD, said the recommendation was not unexpected but was nonetheless disappointing.

"The real impact has to do with the healthcare reform act," said Penson, of Vanderbilt University in Nashville, Tenn. "Coverage for preventive services is tied to the grade that a service is given. Unfortunately, if you get a grade D, then Medicare is not going to cover the service without a copay, and that could really affect access for some patients who might decide they want to have screening."

Penson said he does not consider the USPSTF decision the "end of the road" for PSA testing. The AUA, other healthcare societies, and patient advocacy groups will continue their efforts to ensure that patients who want PSA testing will be able to get it.

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