Shear wave speed imaging of breast lesions: Speed within the lesion, fat-to-lesion speed ratio, or gland-to-lesion speed ratio?

OBJECTIVE: To evaluate the diagnostic performance of shear wave speed (SWS) within the lesion, fat-to-lesion speed ratio (FLR), and gland-to-lesion speed ratio (GLR) for differentiation between benign and malignant breast lesions using a novel SWS imaging technique. METHODS: From April 2016 to June 2016, 182 breast lesions were prospectively included in the study. For each lesion, SWS-lesion, FLR, and GLR were calculated. Pathological results were used as the reference standard. Receiver operating characteristic curves (ROC) were plotted to assess the diagnostic performance. RESULTS: Of the 182 lesions, 142 (78.0%) were benign and 40 (22.0%) were malignant. Significant differences were found between benign and malignant lesions in SWS-lesion, FLR and GLR (2.12±0.64 m/s vs 3.87±1.45 m/s, 1.63±0.61 vs 2.60±1.04, and 1.33±0.39 vs 2.08±0.78, respectively. All P < 0.001). The optimal cut-off values of SWS-lesion, FLR, GLR were 2.88 m/s, 2.31 and 1.51, respectively. The diagnostic performance of SWS-lesion in terms of AUC was the highest (i.e. AUC = 0.845), in comparison with FLR and GLR alone or their combination. The associated sensitivity, specificity, and accuracy for SWS-lesion were 75.0%, 89.4%, and 86.3%, respectively. CONCLUSION: SWS-lesion is a valuable and sufficient method for differentiation between benign and malignant breast lesions.