Digital 2D versus Tomosynthesis Screening Mammography among Women Aged 65 and Older in the United States.

Background Although breast cancer incidence and mortality rates increase with advancing age, there are limited data on the benefits and risks of screening mammography in older women and on the performance of two-dimensional digital mammography (DM) and digital breast tomosynthesis (DBT) in older women. Purpose To compare performance metrics of DM and DBT among women aged 65 years and older. Materials and Methods For this retrospective study, consecutive screening mammograms in patients aged 65 years and older from March 2008 to February 2011 (DM group) and from January 2013 to December 2015 (DBT group) were reviewed. Cancer detection rate, abnormal interpretation rate, positive predictive values, sensitivity, and specificity were calculated. Multivariable logistic regression models were fit to compare performance metrics in the DM versus DBT groups. Results The DM group had 15 019 women (mean age ± standard deviation, 72.7 years ± 6.3), and the DBT group had 20 646 women (mean age, 72.1 years ± 5.9). After adjusting for multiple variables, there was no difference in cancer detection rate between the DM and DBT groups (6.9 vs 8.2 per 1000 examinations; adjusted odds ratio [AOR], 1.13; P = .23). Compared with the DM group, the DBT group had a lower abnormal interpretation rate (5.7% vs 5.8%; AOR, 0.88; P < .001), higher positive predictive value 1 (14.5% vs 11.9%; AOR, 1.26; P = .03), and higher specificity (95.1% vs 94.8%; AOR, 1.18; P < .001). The DBT group had a higher proportion of invasive cancers relative to in situ cancers (81.1% vs 74.4%; P = .06) and fewer node-positive cancers (10.2% vs 16.6%; P = .054) than did the DM group. Conclusion In women aged 65 years and older, integration of digital breast tomosynthesis led to improved performance metrics, with a lower abnormal interpretation rate, higher positive predictive value 1, and higher specificity. © RSNA, 2019 See also the editorial by Philpotts and Durand in this issue.