Characterization of breast lesions: comparison of digital breast tomosynthesis and ultrasonography

Abstract

Objective: To compare the diagnostic performance of digital breast tomosynthesis (DBT) and conventional breast ultrasound (US) to characterize breast lesions as benign or malignant.

Materials and methods: A total of 332 women, presenting for screening examinations or for breast biopsy between March and June 2012 were recruited to undergo digital mammography (DM), DBT, and breast US examination. Among them, 113 patients with 119 breast lesions depicted on DM were finally included. Three blinded radiologists performed an enriched reader study and reviewed the DBT and US images. Each reader analyzed the lesions in random order, assigned Breast Imaging Reporting and Data System (BI-RADS) descriptors, rated the images for the likelihood of malignancy (%) and made a BI-RADS final assessment. Diagnostic accuracy, as assessed by the area under the receiver operating characteristic curve, sensitivity, and specificity of DBT and US were compared.

Results: Among the 119 breast lesions depicted on DM, 75 were malignant and the remaining 44 were benign. The average diagnostic performance for characterizing breast lesions as benign or malignant in terms of area under the curve was 0.899 for DBT and 0.914 for US (p = 0.394). Mean sensitivity (97.3% vs. 98.7%, p = 0.508) and specificity (44.7% vs. 39.4%, p = 0.360) were also not significantly different.

Conclusion: Digital breast tomosynthesis may provide similar reader lesion characterization performance to that of US for breast lesions depicted on DM.

Keywords: Breast US; Diagnostic performance; Digital breast tomosynthesis.

Fig. 1. 62-year-old woman with 1.2 cm-sized invasive ductal carcinoma.

A. Craniocaudal digital mammography view. B. Craniocaudal digital breast tomosynthesis (DBT) view (1-mm section). C. Transverse ultrasonography (US) view. Oval isodense mass (arrows) with indistinct margins is observed on DBT. This lesion appears as hypoechoic lesion with angular margins on US. Readers 1 and 3 categorized this lesion as Breast Imaging Reporting and Data System (BI-RADS) category 3, and reader 2 categorized this lesion as BI-RADS category 4A on DBT. Readers 1 and 2 categorized this lesion as BI-RADS category 4C, and reader 3 categorized this lesion as BI-RADS category 4A on US.

Fig. 2. 57-year-old woman with 1.2 cm-sized invasive papillary carcinoma.

A. Craniocaudal full-field digital mammography view. B. Craniocaudal digital breast tomosynthesis (DBT) (1-mm section) view. C. Transverse ultrasonography (US) view. Mass with spiculated margin is clearly visible on DBT image. This lesion appears as oval circumscribed lesion on US. Readers 1 and 2 categorized this lesion as Breast Imaging Reporting and Data System (BI-RADS) category 4B, and reader 3 categorized this lesion as BI-RADS category 4A on DBT. Readers 2 and 3 categorized this lesion as BI-RADS category 3, and reader 1 categorized this lesion as BI-RADS category 4A on US.

Fig. 3. 63-year-old woman with fibroadenoma (1.3 cm in diameter as measured on ultrasonography [US]).

A. Mediolateral oblique digital mammography view. B. Mediolateral oblique digital breast tomosynthesis (DBT) (1-mm section) view. C. Transverse US view. Round isodense mass with circumscribed margins is observed on DBT. This lesion appears as irregular hypoechoic circumscribed mass on US. Readers 1 and 2 categorized this lesion as Breast Imaging Reporting and Data System (BI-RADS) category 3, and reader 3 categorized this lesion as BI-RADS category 2 on DBT. Readers 1 and 2 categorized this lesion as BI-RADS category 4A, and reader 3 categorized this lesion as BI-RADS category 3 on US.

Fig. 4. 38-year-old woman with 2.5-cm benign phyllodes tumor.

A. Mediolateral oblique digital mammography view. B. Mediolateral oblique digital breast tomosynthesis (DBT) (1-mm section) view. C. Transverse ultrasonography (US) view. Circumscribed high density mass is observed on DBT images. Mass is oval, circumscribed and accompanied by posterior acoustic enhancement on US. All readers categorized this lesion as Breast Imaging Reporting and Data System (BI-RADS) category 4A on DBT. All readers categorized this lesion as BI-RADS category 3 on US.