Role of shear-wave elastography (SWE) in complex cystic and solid breast lesions in comparison with conventional ultrasound

Abstract

Objective: To evaluate the additional role of shear-wave elastography (SWE) in differential diagnosis of complex cystic and solid breast lesions.

Materials and methods: From January 2013 to November 2013, 140 complex cystic and solid breast lesions from 139 consecutive patients were performed ultrasound and SWE prior to biopsy. BI-RADS ultrasound final assessment and SWE parameters were recorded for each lesion. Histopathologic diagnosis was used as the reference standard.

Results: Among the 140 lesions, 30 lesions (21.4%) were malignant. The mean maximum elasticity (Emax) of malignant lesions (184.3 kPa) was significantly higher than that of benign lesions (45.5 kPa) (P<0.001). Homogeneity of elasticity and color pattern were significantly different from malignancy and benign lesions (P<0.05). Emax with cutoff value at 108.5 kPa showed Az value of 0.968 (95% CI, 0.932-0.985) with sensitivity of 86.7% and specificity of 97.3%. Using this cutoff value, false-positive rate was 2.7% and false-negative rate was 13.3%. By applying an Emax value of 108.5 kPa or less as a criterion for downgrading BI-RADS category 4a lesions to category 3 lesions, 103/123 (83.7%) lesions could be downgraded to category 3 lesions.

Conclusion: Additional use of SWE could reduce unnecessary benign biopsies in complex cystic and solid breast lesions.

Keywords: Breast; Cystic lesion; Elastography; Shear-wave; Ultrasound.