Real-time ultrasound elasticity of the breast: initial clinical results

To determine the sensitivity and specificity of a real-time elasticity imaging (EI) ultrasound (US) system in the characterization of breast lesions as benign or malignant.

A total of 208 patients with 251 lesions were scheduled to undergo a US-guided breast biopsy for a mass identified on B-mode US, and each received a real-time elasticity image of the lesion before the biopsy. The lesion size measurements were obtained, and the EI/B-mode size ratio was obtained. The pathology report was obtained and correlated with the EI/B-mode ratio. An EI/B-mode ratio equal to or greater than 1 was considered malignant lesion, whereas EI/B-mode ratios of less than 1 were considered benign. Sensitivity, specificity, positive predictive values, and negative predictive values were calculated.

Of the 251 lesions biopsied, 197 were pathologically benign, and 54 were malignant. Of the 54 malignant lesions, all had an EI/B-mode ratio equal to or greater than 1. Of the 197 benign lesions, 187 had an EI/B-mode ratio of less than 1. Ten benign lesions had an EI/B-mode ratio of greater than 1. The benign lesions that had an EI/B-mode ratio of greater than 1 were lesions with dense fibrosis, and in addition, a characteristic artifact was identified, which was visualized in all simple and complex cysts. The results correspond with a sensitivity of 100%, specificity of 95%, a positive predictive value of 84%, and a negative predictive value of 100%.

Initial results of a real-time EI system for characterization of breast lesions suggest this technique can provide significant new diagnostic information. As a result, this information may significantly improve the ability to select patients for breast biopsy, resulting in a reduction in the number of benign breast biopsies.