Digital Breast Tomosynthesis performs better than 2-dimensional digital mammography as a cancer screening tool for older women.
Bahl, M. et. al.
Digital 2D versus Tomosynthesis Screening Mammography among Women Aged 65 and Older in the United States
Radiology 2019; 00:1-9
Digital breast tomosynthesis (DBT), or 3-dimensional breast imaging, is a mammogram technique that is being used increasingly. It has proven effective at increasing cancer detection and reducing call-backs among women with dense breast tissue. Usually, women with dense tissue are under age 50. For older women, it is often assumed that standard 2-dimensional digital mammography (DM) is entirely appropriate for breast cancer screening. Older women are presumed to have less dense tissue and therefore would derive little to no benefit from DBT.
This group hypothesized that DBT would actually improve the performance of breast cancer screening among an older population. The study compared DM to DBT as breast cancer screening tools for women aged 65 and older. Over 15,000 women receiving DM were compared to over 20,000 women receiving DBT.
For both groups, most women had heterogeneously dense breasts or breasts with scattered fibroglandular densities. The frequencies of extremely dense or entirely fatty tissue were low. The cancer detection rates between the two groups was equivalent. However, the DBT group had a lower rate of abnormal reporting. The DBT group also had a higher positive predictive value (confirmation by tissue evaluation that a suspicious mammogram finding is cancer) as well as a higher specificity (fewer false negatives). Additionally, the DBT group had a higher frequency of invasive cancer detected relative to in situ disease.
This study showed that DBT performed better than DM as a cancer screening tool among women aged 65 and older. These results support the use of DBT among older women for breast cancer screening.