Mammograms Dip in Wake of USPSTF Recommendations

CHICAGO – There has been a clear and abrupt decline in screening mammography in the wake of the controversial breast cancer screening recommendations by the U.S. Preventive Services Task Force.

After climbing steadily at a rate of about 1% per year since 2001, breast mammography among women on Medicare declined 4.3% in 2010, the first full year after the USPSTF recommendations came out.

The reasons for the decline aren’t entirely clear, but it may be that women over age 74 years began to follow the task force recommendations and no longer got screened, or that women aged 50-74 years extended their screening interval from 1 to 2 years, again according to task force recommendations, lead author Dr. David C. Levin said at the annual meeting of the Radiological Society of North America.

^{Patrice Wendling/IMNG Medical Media}

Dr. David Levin

"What is clear is that the introduction of those recommendations in late 2009 had a chilling effect on the willingness of women to get screened," he said. "It remains to be seen whether this trend is going to continue and whether it will affect breast cancer mortality."

For the analysis, Dr. Levin reviewed film and digital screening mammography codes in the Medicare Part B Physician/Supplier Procedure Summary Master Files for 2005 to 2010. The database provides volumes for each code each year.

From these data, he calculated that the screening mammography rate per 1,000 female Medicare beneficiaries had been growing in small increments each year from 311.6 in 2005 to 312.4 in 2006, 316.2 in 2007, 320.1 in 2008, and 322.9 in 2009. This represents a compound annual growth rate of 0.9%.

After the recommendations came out, the screening mammography rate fell to 309.1/1,000 women in 2010, representing a decline of 4.3% in a single year, said Dr. Levin, a radiologist and founder of the center for research on utilization of imaging services at Thomas Jefferson University Hospital in Philadelphia.

He pointed out that earlier this year, Mayo Clinic researchers reported a 5.7% decline in screening mammography in 2010 among women aged 40-64, based on data from almost 7.9 million women enrolled in nearly 100 health plans.

In a separate presentation at the meeting, investigators analyzed the outcomes of 43,351 screening mammograms performed between 2007 and 2010 to determine how the new USPSTF recommendations against screening in women 40-49 years could impact this age group.

The cross-sectional analysis included all patients presenting for a screening mammogram without clinical findings at New York Presbyterian Hospital–Weill Cornell Medical College (NYPH-WCMC) in New York City. Women aged 40-49 comprised 33.5% of the screening population.

Dr. Elizabeth Arleo

During the 4 years, 205 breast cancers were detected (4.7/1,000). Women in their forties accounted for 19% of the cancers found, which would represent a substantial degree of underdiagnoses if they had been missed, reported Dr. Elizabeth Arleo, a radiologist at NYPH-WCMC.

Notably, only three of the women in their forties with screen-detected breast cancer had a first-degree relative with premenopausal breast cancer, thereby placing them at higher risk. More than half of the cancers in this subgroup, however, were invasive (21/39).

If the USPSTF recommendations had been enforced during the study years, these cancers may not have been detected until the patients’ baseline screening at age 50 or until the cancers had progressed to clinically evident, palpable disease, Dr. Arleo coauthors said.

Dr. Levin reported relationships with HealthHelp and Outpatient Imaging Affiliates. Dr. Arleo said she had no relevant financial disclosures.