Comparing Tumor Characteristics and Rates of Breast Cancers Detected by Screening Digital Breast Tomosynthesis and Full-Field Digital Mammography

OBJECTIVE. The purpose of this study was to compare the cancer detection rates (CDRs), tumor types, and characteristics between screening digital breast tomosynthesis (DBT) and screening full-field digital mammography (FFDM) in a matched patient population in a large academic breast imaging practice with mixed DBT and FFDM technology. MATERIALS AND METHODS. In this retrospective study, we reviewed consecutive screening FFDM and DBT examinations performed between October 2012 and September 2014. To control for nonrandomized selection of FFDM versus DBT examinations, we applied propensity score matching on the basis of patient age, imaging site, and prior imaging findings. An institutional breast cancer registry identified cancer diagnoses. CDR and tumor type, grade, receptor, nodal status, and size were compared between matched FFDM and DBT groups. RESULTS. Sixty-one cancers were detected in the matched screening cohort of DBT (n = 9817) and FFDM (n = 14,180) examinations. CDR was higher with DBT than with FFDM for invasive cancers (2.8 vs 1.3, p = 0.01), minimal cancers (2.4 vs 1.2, p = 0.03), estrogen receptor-positive invasive cancers (2.6 vs 1.1, p = 0.01), and node-negative invasive cancers (2.3 vs 1.1, p = 0.02.), respectively. The ratio of screen-detected invasive cancers to ductal carcinoma in situ on DBT (3.0) was not significantly different from that on FFDM (2.6) (p = 0.79). CONCLUSION. DBT results in an overall increase in CDR irrespective of the tumor type, size, or grade of cancer.