To evaluate the effect of supplemental ABUS to mammography-based breast cancer screening in a large cohort of Asian women.

A retrospective database search identified asymptomatic Korean women who underwent screening mammography and supplemental ABUS between Jan 2018 and Dec 2019. Performance measures of mammography alone and ABUS plus mammography were compared. Subgroup analyses were performed based on mammography density (dense versus nondense breasts).

A total of 2301 women (mean±standard deviation, 52.0 ± 9.0 years) with 2785 consecutive screening examinations were included. Of these, 26 cancers were diagnosed, of which eight were detected only with supplemental ABUS. Supplemental ABUS to mammography yielded additional cancer detection rate (CDR) 2.9 per 1000 examinations (95% confidence interval [CI]: 1.1, 5.0; P = 0.006). The sensitivities of ABUS plus mammography versus mammography alone were 92.9% (95% CI: 81.8, 100.0) and 64.3% (95% CI: 45.7, 82.6), the abnormal interpretation rates (AIRs) were 12.1% (95% CI: 10.9, 13.3) and 5.5% (95% CI: 4.6, 6.3), respectively. For women with dense breasts, supplemental ABUS resulted in additional CDR of 2.8 per 1000 examinations (95% CI: 0.9, 5.5; P = 0.02) and increased sensitivity by 27.3% (95% CI: 8.7, 47.9; P = 0.006), but increased AIR by 7.9% (95% CI: 6.8, 9.1; P < 0.001). For women with nondense breasts, CDR and sensitivity did not show significant improvement, but AIR increased by 2.2% (95% CI: 1.2, 3.5; P < 0.001).

Addition of ABUto mammography yielded an additional CDR of 2.8 per 1000 examinationin Asian women with dense breasts, with a substantial increase in the abnormal interpretation rate. No benefit of supplemental ABUwaobserved in Asian women with nondense breasts.

Supplemental automated breast ultrasound can provide significant benefits in women with dense breasts, but not for nondense breasts.