Clinical Performance Metrics of 3D Digital Breast Tomosynthesis Compared With 2D Digital Mammography for Breast Cancer Screening in Community Practice

OBJECTIVE. The objective of our study was to assess the clinical performance of combined 2D-3D digital breast tomosynthesis (DBT), referred to as ''3DDBT,'' compared with 2D digital mammography (DM) alone for screening mammography in a community-based radiology practice. MATERIALS AND METHODS. Performance outcomes measures were assessed for 14 radiologists who interpreted more than 500 screening mammography 3D DBT studies after the initiation of tomosynthesis. Outcomes from screening mammography during the study period between August 9, 2011, and November 30, 2012, using 3D DBT (n = 23,149 patients) versus 2D DM (n = 54,684 patients) were compared. RESULTS. For patients screened with 3D DBT, the relative change in recall rate was 16.1% lower than for patients screened with 2D DM (p > 0.0001). The overall cancer detection rate (CDR), expressed as number of cancers per 1000 patients screened, was 28.6% greater (p = 0.035) for 3D DBT (6.3/1000) compared with 2D DM (4.9/1000). The CDR for invasive cancers with 3D DBT (4.6/1000) was 43.8% higher (p = 0.0056) than with 2D DM (3.2/1000). The positive predictive value for recalls from screening (PPV1) was 53.3% greater (p = 0.0003) for 3D DBT (4.6%) compared with 2D DM (3.0%). No significant difference in the positive predictive value for biopsy (PPV3) was found for 3D DBT versus 2D DM (22.8% and 23.8%, respectively) (p = 0.696). CONCLUSION. In community-based radiology practice, mammography screening with 3D DBT yielded lower recall rates, an increased CDR for cancer overall, and an increased CDR for invasive cancer compared with 2D DM. The PPV1 was significantly greater in the group screened using 3D DBT.