Screening Digital Mammography Recall Rate: Does It Change with Digital Breast Tomosynthesis Experience?

Purpose To compare screening mammography recall rate, cancer detection rate (CDR), and positive predictive values (PPVs) for digital mammography before and after radiologist experience with digital breast tomosynthesis (DBT). Materials and Methods This retrospective study was approved by the institutional review board and compliant with HIPAA. The authors reviewed screening mammography audit data obtained from 2009 to 2014, during which 108 276 digital mammographic examinations were performed (50 062 before and 58 214 after experience with DBT). Recall rate, CDR, PPV of positive screening result (PPV₁), PPV of biopsy recommendation (PPV₂), and PPV of biopsies performed (PPV₃) of digital mammography for six radiologists were compared before (2009-2011) and after (2012-2014) experience with DBT. Radiologists worked in both a community setting, in which only digital mammography was available, and in two tertiary breast imaging centers, where they interpreted DBT images starting in 2012. Data were examined by using generalized linear mixed modeling wherein observations were nested for each radiologist over time. P < .05 was considered indicative of a statistically significant difference; 95% confidence intervals (CIs) were calculated. Results The average recall rate was 6.8% (range, 3.6%-9.7%) before experience with DBT and 7.9% (range, 5.5%-9.5%) after (P = .0316). Before experience with DBT, the recall rate increased only 0.01% for each year from 2009 to 2011 (P = .9727). After experience with DBT, the recall rate increased 0.65% for each year from 2012 to 2014 (P < .0127). CDR increased from 2.5 per 1000 examinations (95% CI: 2.2, 2.9) to 3.5 per 1000 examinations (95% CI: 3.0, 4.0; P = .0203). PPV₂ and PPV₃ increased significantly after experience with DBT, from 26.9% (95% CI: 19.9%, 35.3%) to 36.1% (95% CI: 31.7%, 40.7%; P = .0212) for PPV₂ and from 31.2% (95% CI: 24.0%, 39.3%) to 40.0% (95% CI: 35.5%, 44.6%; P = .0290) for PPV₃. Conclusion Recall rate, CDR, PPV₂, and PPV₃ of digital mammography increased after radiologist experience with DBT. ^© RSNA, 2017.