Clinical Performance of Synthesized Two-dimensional Mammography Combined with Tomosynthesis in a Large Screening Population

Purpose To compare the clinical performance of synthesized two-dimensional (s2D) mammography combined with digital breast tomosynthesis (DBT) with that of full-field digital mammography (FFDM) alone and FFDM combined with DBT in a large community-based screening population by analyzing recall rate, positive predictive value, and cancer detection rate. Materials and Methods This was a retrospective study approved by the institutional review board and was HIPAA compliant with waiver of informed consent. A total of 78 810 screening mammograms from October 11, 2011, to June 30, 2016, were retrospectively collected. Of these, 32 076 were FFDM, 30 561 were DBT-FFDM, and 16 173 were DBT-s2D mammograms. Diagnostic performance of FFDM, DBT-FFDM, and DBT-s2D mammography was compared. Statistical significance was determined by using the Pearson χ test and was expressed as odds ratios and related confidence intervals determined by means of logistic regression analysis with pairwise comparisons. Results Recall rates were significantly lower with DBT-s2D mammography (4.3%, 687 of 16 173) when compared with DBT-FFDM (5.8%, 1785 of 30 561; odds ratio, 0.72; 95% confidence interval: 0.65, 0.78; P < .0001) and when compared with FFDM alone (8.7%, 2799 of 32 076; odds ratio, 0.46; 95% confidence interval: 0.43, 0.51). The cancer detection rate was similar among FFDM alone (5.3 of 1000 screening examinations), DBT-FFDM (6.4 of 1000 screening examinations), and DBT-s2D mammography (6.1 of 1000 screening examinations) with no significant difference (FFDM vs DBT-FFDM, P = .08; FFDM vs DBT-s2D, P = .27). The percentage of invasive cancers detected was significantly higher with DBT-s2D mammography (76.5%) than with DBT-FFDM (61.3%, P = .01), and positive predictive values with DBT-s2D mammography (40.8%) were significantly higher than those with DBT-FFDM (28.5%, P < .0001). Conclusion Screening with DBT-s2D mammography in a large community-based practice improved recall rate and positive predictive values without loss of cancer detection rate when compared with DBT-FFDM and FFDM alone. RSNA, 2017.