Digital Breast Tomosynthesis Plus Ultrasound Versus Digital Mammography Plus Ultrasound for Screening Breast Cancer in Women With Dense Breasts

Abstract

Objective: To compare the outcomes of digital breast tomosynthesis (DBT) screening combined with ultrasound (US) with those of digital mammography (DM) combined with US in women with dense breasts.

Materials and methods: A retrospective database search identified consecutive asymptomatic women with dense breasts who underwent breast cancer screening with DBT or DM and whole-breast US simultaneously between June 2016 and July 2019. Women who underwent DBT + US (DBT cohort) and DM + US (DM cohort) were matched using 1:2 ratio according to mammographic density, age, menopausal status, hormone replacement therapy, and a family history of breast cancer. The cancer detection rate (CDR) per 1000 screening examinations, abnormal interpretation rate (AIR), sensitivity, and specificity were compared.

Results: A total of 863 women in the DBT cohort were matched with 1726 women in the DM cohort (median age, 53 years; interquartile range, 40-78 years) and 26 breast cancers (9 in the DBT cohort and 17 in the DM cohort) were identified. The DBT and DM cohorts showed comparable CDR (10.4 [9 of 863; 95% confidence interval {CI}: 4.8-19.7] vs. 9.8 [17 of 1726; 95% CI: 5.7-15.7] per 1000 examinations, respectively; P = 0.889). DBT cohort showed a higher AIR than the DM cohort (31.6% [273 of 863; 95% CI: 28.5%-34.9%] vs. 22.4% [387 of 1726; 95% CI: 20.5%-24.5%]; P < 0.001). The sensitivity for both cohorts was 100%. In women with negative findings on DBT or DM, supplemental US yielded similar CDRs in both DBT and DM cohorts (4.0 vs. 3.3 per 1000 examinations, respectively; P = 0.803) and higher AIR in the DBT cohort (24.8% [188 of 758; 95% CI: 21.8%-28.0%] vs. 16.9% [257 of 1516; 95% CI: 15.1%-18.9%; P < 0.001).

Conclusion: DBT screening combined with US showed comparable CDR but lower specificity than DM screening combined with US in women with dense breasts.

Keywords: Breast cancer; Digital breast tomosynthesis; Mammography; Screening; Ultrasound.

Fig. 1. Study flow chart. This flow chart show the study population selection process, including inclusion criteria, and exclusion criteria. 1:2 matching was performed for women in digital breast tomosynthesis (DBT) and digital mammography (DM) cohorts,and another 1:2 matching was performed for women with negative assessments on DBT and DM. US = ultrasound

Fig. 2. Imaging of a 56-year-old woman with a screening breast ultrasound (US) detected invasive ductal cancer (T1N0M0, estrogen receptor, progesterone receptor positive, and human epithelial growth factor receptor 2 negative). Images from the breast tomosynthesis in the left craniocaudal (A) and left mediolateral oblique (B) views show no definite suspicious lesions in the left breast. C: Breast US showing an irregular mass in the left breast (arrows). D: The patient underwent US-guided wire localization before breast-conserving surgery, and digital mammography in the left mediolateral oblique view obtained after US-guided wire localization did not show any suspicious findings at the site of the wire. A marker was attached on the skin of the nipple entry site.

Fig. 3. Imaging of a 61-year-old woman with a screening breast ultrasound (US) revealed invasive ductal cancer (T1N1M0, estrogen receptor, progesterone receptor positive, and human epithelial growth factor receptor 2 negative). Digital mammography images of the left craniocaudal (A) and left mediolateral oblique (B) views show no definite suspicious lesions in the left breast. C: Breast US showing an irregular mass in the left breast (arrows). D: The patient underwent US-guided wire localization before breast-conserving surgery. Digital mammography in the left mediolateral oblique view obtained after US-guided wire localization did not show any suspicious findings at the site of the wire. A marker was attached on the skin of the nipple entry site.