Objectives: To report our preliminary experience with shear-wave elastography (SWE) for non-mass lesions (NMLs) in the breast and suggest a potential ancillary role of SWE for BI-RADS Category 4a NMLs in reducing the number of unnecessary benign biopsies.
Methods: A total of 310 breast lesions in 286 consecutive women who had been scheduled for US-guided automated gun biopsy or vacuum-assisted biopsy between June and December 2012 were initially included in this study. Finally, 33 women with 34 breast lesions classified as NMLs constituted our study population. Diagnostic performances of each quantitative SWE parameter were calculated. Histological diagnosis was used as a reference standard.
Results: Among the 34 breast NMLs, 22 (65%) were benign and 12 (35%) were malignant. Emean value with cut-off set at 41.6 kPa had the highest Az value 0.788 (95% CI, 0.625-0.951), showing sensitivity of 83.3% and specificity of 68.2%. By applying an Emean value of 41.6 kPa or less as a criterion for downgrading soft BI-RADS category 4a NMLs to category 3 NMLs, 15 unnecessary biopsies could have been eliminated from the 19 BI-RADS category 4a lesions (79%).
Conclusions: SWE features could increase positive predictive values and reduce unnecessary benign biopsies of category 4a NMLs.
Key points: • Ultrasound elastography is increasingly used to assess the stiffness of breast lesions • Shear-wave elastography provides useful information about non-mass breast lesions • Shear-wave elastography may render some biopsies of non-mass breast lesions unnecessary.