Digital breast tomosynthesis and breast ultrasound: Additional roles in dense breasts with category 0 at conventional digital mammography

Purpose: To compare the diagnostic performances of digital breast tomosynthesis (DBT) and ultrasound for the dense breasts with category 0 at conventional digital mammography.

Materials and methods: This retrospective study was approved by the institutional review board, and informed consent was waived. Among the 1103 patients who underwent screening digital mammography at our institution, 769 (69.7%) patients had dense breasts. Of the 769 patients, 229 (29.8%) lesions were categorized as 0. DBT, breast ultrasound and digital mammography were performed in 108 (47.2%) patients. BI-RADS final assessments for DBT and ultrasound were recorded. Categories 1-3 were clinically considered as benign, and categories 4 and 5 were clinically considered as malignant. The diagnostic performances of breast ultrasound and DBT were correlated with final pathologic reports or follow-up images.

Results: Among 108 lesions, 17 (15.7%) were malignant and 91 (84.3%) were benign. Sensitivity was 100% for both ultrasound (17/17) and DBT (17/17) and negative predictive value was also 100% for both ultrasound (49/49) and DBT (74/74). Specificity and positive predictive value for ultrasound were 53.9% (49/91) and 28.8% (17/59), respectively. Specificity and positive predictive value for DBT were 81.3% (74/91) and 50% (17/34), respectively. DBT showed higher diagnostic accuracy than that of breast ultrasound (DBT: 84.3%, 91/108; ultrasound: 61.1%, 66/108; p<0.001). The benign biopsy rate of DBT (50%, 17/34) was lower than that of ultrasound (71.2%, 42/59).

Conclusion: DBT showed better diagnostic performance than breast ultrasound for dense breasts with category 0. DBT may reduce the benign biopsy rate and short term follow-up.