Tomo breast screening add-on is cost-effective, especially before 50

Adding annual screening tomosynthesis to 2D mammography beginning at age 40 is cost-effective compared with 2D mammography alone, according to a study published online Aug. 23 in the American Journal of Roentgenology.

However, the net monetary benefits of the extra exam are around three times greater for women in their 40s than for those in their 50s and older—a finding that may have ramifications for the perpetually disputed recommendations around mammography screening.

Vivek Kalra, MD, and colleagues at Yale arrived at these conclusions after constructing a decision-tree analysis that considered the federal payer perspective with a lifetime horizon.

They incorporated data from a multiinstitutional study of more than 450,000 patients, institutional data of 13,000 patients, literature values and Medicare reimbursement rates.

They calculated cost-effectiveness using incremental ratios and net monetary benefit (NMB) calculations, performing sensitivity analyses to ascertain the implication of changes in recall rates, disutility for false-positives and other variables.

The researchers’ base-case analysis showed an incremental cost per quality-adjusted life year gained for tomosynthesis over 2D alone for all ages of $20,230.

In the 40- to 49-year-old subgroup, net monetary benefit per decade was an impressive $1,598.

The NMB dropped precipitously from there for the older age subgroups: $546 for women in their 50s, $535 for those in their 60s and $501 for those in their 70s.  

“Prevalence of denser breasts in younger populations and larger decreases in recall rate after tomosynthesis in patients with dense breasts are the presumed key drivers” for the NMB falloff after 50, the authors write in their discussion.

Meanwhile, tomosynthesis was the better strategy in 63.2 percent of the iterations according to probabilistic sensitivity analysis, Kalra and co-authors found.

Among the study limitations the authors acknowledge is a lack of consensus in the literature about values for quality-adjusted life years (QALY) disutility factors.

“These disutility factors incorporate inherently subjective intangible healthcare-related factors such as discomfort, pain and anxiety, and variable factors not related to healthcare such as lost job time, transportation and child care,” the authors write, noting that published values for diagnostic workup disutility range from 1.3 percent to 11 percent.

They suggest that future analyses incorporating large age-subgroup datasets and adding further downstream costs—along with the hoped-for development of consensus disutility factors—could produce an even more compelling fiscal case for adding annual screening tomosynthesis to 2D mammography beginning at age 40.

In any case, the trebled differential in net monetary benefits for 40-something women compared with those 50 and older “may,” the authors write, “warrant reevaluation of mammography screening recommendations.”