Study questions cost effectiveness of supplemental screening for women with dense breasts

Despite the spread of state legislation requiring breast density notification, a recent study has deemed supplemental ultrasonography (US) an expensive supplementary screening method that provides “relatively small benefits.”

The study was published online Dec. 9 in the Annals of Internal Medicine and sought to evaluate the potential value and cost-effectiveness of supplemental US screening for women with dense breasts.

It is estimated that 40 percent of women between 40 and 74 years of age have dense breasts, and breast density notification laws have been enacted in 19 states, with legislation also under consideration at the federal level. Supplemental screening, often in the form of US, is suggested for women with dense breasts.

Dense breasts are defined as “heterogeneously or extremely dense breast tissue” by the American College of Radiography’s Breast Imaging Reporting and Data System (BI-RADS).

Brian L. Sprague, PhD, with the University of Vermont, and colleagues contend in the study that the effects of additional US screening, as well as any potential side effects, have not been thoroughly studied in light of new legislation.

“Moreover, the effect of supplemental ultrasonography screening on long-term outcomes, such as breast cancer mortality and its cost-effectiveness at a population level are unknown,” Sprague and colleagues wrote.

For the study, the researchers used three validated simulation models that incorporated lifetime horizon and federal payer perspective. These models simulated life histories of women at risk for breast cancer, had screening, were treated for breast cancer diagnosed by either screening or clinical detection and were at risk of dying of breast cancer.

“The models approximately replicated U.S. breast cancer incidence and mortality trends,” the authors wrote.

The models estimated 25.4 breast cancer deaths per 1,000 women and found that mammography screening alone reduced the number to 19.7 breast cancer deaths per 1,000.

“Relative to ’no screening,’ these gains came at an increase in total of approximately $1 million per 1,000 women for biennial mammography screening for those aged 50 to 74 years and $3 million per 1,000 women for annual mammography screening for those aged 40 to 74,” the researchers wrote.

The model estimated that in women between 50 and 74 years old who underwent biennial mammograms, a push for supplemental screening would result in 504 US screenings per 1,000 women in women with extremely dense breasts and 3,827 US screenings per 1,000 women in women with heterogeneously or extremely dense breasts.

The team found that the incremental cost effectiveness of expanding supplemental US beyond women with extremely dense breasts to women with heterogeneously or extremely dense breasts was $338,000 per quality-adjusted life year (QALY) gained in the biennial screening group of women ages 50 to 74 and $776,000 per QALY gained for women screened annually between the ages of 40 and 74 years.

“Our findings indicated that supplemental [US] screening of women with dense breasts would substantially increase costs while producing small benefits in breast cancer deaths averted and QALYs gained,” Sprague and team wrote.

The leading breast density notification advocacy group was quick to refute the study.

“Nothing could be further from the truth,” said Nancy M. Cappello, PhD, founder of Are You Dense Inc. in a press release.  “Computer projections using past fixed data to project the future is problematic.  The future of technology changes so rapidly that this analysis lacks relevance to the now and beyond.”

Additionally, Cappello said dense breast tissue is the strongest predictor of the failure of mammography to detect cancer—missing 50 percent of cancers in dense breasts.