Gland/Lesion Strain Ratio for Predicting Malignancy of Solid Breast Lesions in Chinese Patients

Objectives: To determine an optimal cut-off for gland/lesion strain ratio (GLR) in differentiation of benign and malignant breast lesions. The diagnostic performances of elasticity score, Breast Imaging Reporting and Data System (BI-RADS), and modified BI-RADS category were also assessed. Methods: A retrospective review of all consecutive new solid breast lesions with B-mode ultrasound and strain elastography assessment was conducted in a regional hospital in Hong Kong from January 2017 to January 2018. Included subjects were Chinese women with diagnostic breast imaging and subsequent histological evaluation for BI-RADS 3 to 5 solid breast lesion(s). Modified BI-RADS was determined by incorporating the two elastography parameters. Results were analysed using Mann-Whitney U test and receiver operating characteristic curves. Results: GLR for smaller lesions of 2 cm, median GLR and elasticity score were significantly lower in benign lesions (p < 0.05). Taking an optimal GLR cut-off at 2.62, sensitivity of 84.5% and specificity of 81.4% were yielded. The optimal cut-off of elasticity score was 3.5, giving sensitivity of 93.1% and specificity of 81.4%. With these two cut-off thresholds, modified BI-RADS showed an area under the receiver operating characteristic curve (Az) of 0.906. The Az were 0.852 for GLR, 0.926 for elasticity score and 0.827 for BI-RADS. Modified BI-RADS showed higher Az than BI-RADS (p < 0.05). Conclusion: GLR showed reasonable diagnostic performance for breast lesions of ≥1 cm in our cohort. Modifying BI-RADS with GLR and elasticity score can improve diagnostic accuracy.