Experts discuss USPSTF mammography recommendations

The USPTF recommendations for breast cancer screening remain controversial.

In November, the U.S. Preventive Services Task Force released a new set of recommendations that suggested that annual mammograms for women aged between 40 and 49 were unnecessary and potentially harmful. Since then, the recommendations have been widely discussed in the medical and lay communities.

The updated recommendations advised against routine screening for women aged 40 to 49 years, but stressed that the decision to begin biennial mammography before age 50 should be made by a patient and her physician. The task force further recommended that women aged from 50 to 74 years only needed biennial screening rather than annual, and that there is not enough evidence to fully weigh the benefits and harms of mammography for women aged 75 years and older.

These recommendations, which some experts thought sent the wrong message, caused controversy. Writing in an editorial recently published in the Journal of the American Medical Association,Steven Woloshin, MD, MS, and Lisa M. Schwartz, MD, MS, of the VA Outcomes Group, White River Junction, Vt., and the Dartmouth Institute for Health Policy and Clinical Practice, Hanover, N.H., wrote, “for years, physicians and patients have received a simple message about cancer screening, ‘Take the test not the chance.’” In fact, in one survey, 87% of surveyed U.S. adults said that cancer screening was “almost always a good idea.” These new recommendations seemed to call that belief into question.

Further complicating matters, the task force recommendations came in the midst of the Obama Administration’s plans to reform health care. Amidst claims of government rationing of health care and “death panels,” critics charged that the recommendations were evidence that the government was willing to risk lives to save money.

Weighing risks, benefits

In addition to Woloshin and Schwartz, a number of experts revisited both the clinical ramifications of the recommendation and the attendant political fallout in a recent issue of the Journal of the American Medical Association.

One of the experts, Steven H. Woolf, MD, MPH, a professor in the department of family medicine at Virginia Commonwealth University and a former member of the task force, emphasized that the USPSTF never recommended against mammograms. Instead, he wrote, the task force recommended against routine screening of women aged 40 to 49 without also discussing potential risks associated with mammography.

“They are trying to encourage clinicians to give women better information about the tradeoffs between benefits and harms,” he said in an interview with HemOnc Today. “That’s a good idea for all women considering mammograms, but it’s something they felt was especially important for younger women because the tradeoffs are a closer call in that population.”

As Woolf noted in his editorial, at least 1,000 women aged between 39 and 49 have to undergo screening to save one woman’s life, and younger women are at increased risk for false-positive results, unnecessary biopsies, anxiety and overtreatment.

“Advocates of mammography and cancer survivors often belittle these harms, but a moral duty exists when subjecting millions of asymptomatic women to a procedure that benefits relatively few,” he wrote.

Worth the risk?

In her editorial, Wendie A. Berg, MD, PhD, a radiologist with American Radiology Services who specializes in breast imaging, wrote that 63% of women in one survey felt that trading 500 or more false-positive results per one life saved was a reasonable exchange.

She wrote that of 1,000 women in their 40s who have a mammogram, only 15 will be recommended for biopsy and two to five of those women will have cancer. She said that 75% of breast cancers are diagnosed in women who are asymptomatic and that to achieve the full benefit of mammography, women should be screened annually. Berg called the task force’s recommendations “problematic.”

“Screening mammography is the only test to date proven to reduce deaths due to breast cancer,” she wrote. “Annual mammographic screening is appropriate starting at age 40 years, provided the woman is willing to accept the downsides of false positives, including being recalled for more imaging and the possibility of a needle biopsy for a finding that is not breast cancer. The overwhelming majority of women are willing to accept these downsides as part of the process of saving lives otherwise lost to breast cancer.”

Still, 40% of women in a study cited by Woloshin and Schwartz described a false-positive result as “the scariest time of my life” even if they later concluded they were glad they had undergone the screen. With the ratio of women who are over-diagnosed based on false-positive results per life-saved ranging from 2:1 to 10:1, the task force concluded that “benefit outweighs harm for women aged 50 to 74 years, but not for women younger than age 50 years.”

“Over-diagnosed women are unnecessarily diagnosed, undergo treatment that can only cause harm and must live with ongoing fear of cancer recurrence,” wrote Woloshin and Schwartz.

In another editorial, Ann M. Murphy, MD, a pediatric cardiologist and researcher with the Johns Hopkins NHLBI Proteomics Center and a breast cancer survivor, points out nuances in the task force’s message that may have been lost. Mammography, she wrote, does not have the sensitivity or specificity found in an ideal screening test and “is particularly problematic in younger women.”

According to her, physicians must not only discuss the potential risks involved with mammogram, but also the factors that might mitigate that risk such as the use of digital mammography or referrals to medical centers where biopsy can be done with core needle approach rather than surgery.

“Clinicians and those who speak to the public need to be honest in conveying the potential benefits and risks of mammography for screening, particularly in 40- to- 49-year-olds,” she wrote. “All women should have the opportunity to discuss the potential benefit and risk of screening mammography with their clinicians to arrive at an individualized decision about care.”

Future recommendations

Ultimately, the biggest change that may result from these recommendations may come to the task force itself. Woolf said the organization has long taken pride in making strictly evidence-based and apolitical recommendations, but task force officials may have to pay more attention to the potential political ramifications of their positions.

“For the task force, I think they need to put more effort into packaging and communicating their conclusions in future recommendations, especially when they concern controversial topics,” he said. “This painful experience has probably convinced them they should do that.

“But apart from what this specific task force does, we in our society need to come up with a better way for discussing these issues so we don’t use ‘Larry King Live’ and formats like that to make decisions about these very important life-and-death matters.” – by Jason Harris

Berg WA. JAMA. 2010;303:168-1693.

DeAngelis CD. JAMA. 2010;303:172-173.

Murphy AM. JAMA. 2010;303:166-167.

Woloshin S. JAMA. 2010;303:164-165.

Woolf SH. JAMA. 2010;303:162-163.