The use of digital breast tomosynthesis (DBT) has been associated with increases in specificity and breast cancer detection compared with digital mammography (DM) alone. However, most published studies employed data from first- or prevalent-round screening rather than incident-round screening. In addition, few studies contained data such as age, breast density, and cancer molecular subtypes. Therefore, the role of DBT in breast cancer screening across all ages, breast density groups, and tumor subtypes remains unclear. In this prospective cohort study, 96,269 women age 40 to 74 years who underwent screening examinations using DM and DBT were evaluated to study the primary outcomes of recall rate, cancer detection rate, positive predictive value, biopsy rate, and distribution of invasive cancer subtypes, as well as their associations with DM and DBT. Of 180,340 breast cancer screening examinations performed, 71.7% used DM and 28.3% used DBT. DBT was slightly more common among younger women, women with dense breasts, and those undergoing their first screening. Researchers found that the recall rate was lower for DBT compared with DM (8.7% vs. 11.2% respectively, OR 0.64, 95% CI 0.57 to 0.72, p<0.001), and that the breast cancer detection rate was higher with DBT than with DM for all age groups (OR 1.41, 95% CI 1.05 to 1.89, p=0.02). Overall breast cancer rates were higher with DBT than with DM (OR 1.47, 95% CI 1.12 to 1.94, p=0.01), with the greatest association among women aged 40 to 49 years (OR 1.70, 95% CI 1.04 to 2.77, p=0.03). For these younger women, breast cancers detected by DBT were less often classified as advanced cancers compared with cancers detected through DM, however, this difference was not statistically significant (25% vs. 40.4%, p=0.17). After adjusting for confounding factors, screening examinations with DBT were associated with higher specificity (OR 1.46 95% CI 1.30 to 165, p<0.001). Overall, results from this study suggest that DBT may have a higher specificity for breast cancer than DM, and supports the use of DBT screening in younger women.
©2019 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.