In addition to the increase in the CDR, another benefit of adding DBT to 2-D mammography is the reduction in the recall rate [16-19]. In a single-center screening program, Sharpe et al [18] reported a reduction in the recall rate by 18.8%. In the prospective Oslo Tomosynthesis Screening Trial, the recall rate was reduced from 6.7/1,000 to 3.6/1,000 [19]. There is also evidence that the reduction in the recall rate is maintained over consecutive screening episodes [18]. At a high-volume screening center, when women with heterogeneously or extremely dense breast tissue were offered automated 3-D US screening in addition to full-field digital mammography (FFDM), the added CDR rose by 2.4/1,000 screened (6.6/1,000 automated 3-D US screening plus FFDM versus 4.2/1,000 for FFDM alone) [59]. However, the risk level of the population was not defined other than patients with a personal history of breast cancer were excluded, and 3.5% of the patients reported a family history of breast cancer. Buchberger et al [60] compared the performance of screening mammography with and without screening US in average-risk women. In the subgroup of women with dense breasts, the CDR increased from 1.8/1,000 to 2.4/1,000, with the addition of screening US. However, the PPV2 decreased from 52.7/1,000 with mammography alone to 37.7/1,000 with mammography plus US. For the entire population, there were 28 interval cancer rates within a 12- month period after screening (0.42/1,000): 18 in women with dense breasts and 10 in women with nondense breasts. In the Japan Strategic Anti-cancer Randomized Trial, 72,998 asymptomatic women 40 to 49 years of age were randomized to mammographic screening alone or mammographic plus US screening [61]. The sensitivity and specificity in the mammogram arm were 77.0% and 91.4%, respectively. In comparison, the mammogram plus US arm had a higher sensitivity (91.1%) but lower specificity (87.7%).
Supplemental Breast Cancer Screening Based on Breast Density. In addition to the increase in the CDR, another benefit of adding DBT to 2-D mammography is the reduction in the recall rate [16-19]. In a single-center screening program, Sharpe et al [18] reported a reduction in the recall rate by 18.8%. In the prospective Oslo Tomosynthesis Screening Trial, the recall rate was reduced from 6.7/1,000 to 3.6/1,000 [19]. There is also evidence that the reduction in the recall rate is maintained over consecutive screening episodes [18]. At a high-volume screening center, when women with heterogeneously or extremely dense breast tissue were offered automated 3-D US screening in addition to full-field digital mammography (FFDM), the added CDR rose by 2.4/1,000 screened (6.6/1,000 automated 3-D US screening plus FFDM versus 4.2/1,000 for FFDM alone) [59]. However, the risk level of the population was not defined other than patients with a personal history of breast cancer were excluded, and 3.5% of the patients reported a family history of breast cancer. Buchberger et al [60] compared the performance of screening mammography with and without screening US in average-risk women. In the subgroup of women with dense breasts, the CDR increased from 1.8/1,000 to 2.4/1,000, with the addition of screening US. However, the PPV2 decreased from 52.7/1,000 with mammography alone to 37.7/1,000 with mammography plus US. For the entire population, there were 28 interval cancer rates within a 12- month period after screening (0.42/1,000): 18 in women with dense breasts and 10 in women with nondense breasts. In the Japan Strategic Anti-cancer Randomized Trial, 72,998 asymptomatic women 40 to 49 years of age were randomized to mammographic screening alone or mammographic plus US screening [61]. The sensitivity and specificity in the mammogram arm were 77.0% and 91.4%, respectively. In comparison, the mammogram plus US arm had a higher sensitivity (91.1%) but lower specificity (87.7%).