Comparison and Combination of Strain and Shear Wave Elastography of Breast Masses for Differentiation of Benign and Malignant Lesions by Quantitative Assessment: Preliminary Study

Abstract

Objectives-To compare the diagnostic performance of strain and shear wave elastography of breast masses for quantitative assessment in differentiating benign and malignant lesions and to evaluate the diagnostic accuracy of combined strain and shear wave elastography.Methods-Between January and February 2016, 37 women with 45 breast masses underwent both strain and shear wave ultrasound (US) elastographic examinations. The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) final assessment on B-mode US imaging was assessed. We calculated strain ratios for strain elastography and the mean elasticity value and elasticity ratio of the lesion to fat for shear wave elastography. Diagnostic performances were compared by using the area under the receiver operating characteristic curve (AUC).Results-The 37 women had a mean age of 47.4 years (range, 20-79 years). Of the 45 lesions, 20 were malignant, and 25 were benign. The AUCs for elasticity values on strain and shear wave elastography showed no significant differences (strain ratio, 0.929; mean elasticity, 0.898; and elasticity ratio, 0.868; P > .05). After selectively downgrading BI-RADS category 4a lesions based on strain and shear wave elastographic cutoffs, the AUCs for the combined sets of B-mode US and elastography were improved (B-mode 1 strain, 0.940; B-mode 1 shear wave; 0.964; and B-mode, 0.724; P < .001). Combined strain and shear wave elastography showed significantly higher diagnostic accuracy than each individual elastographic modality (P 5 .031).Conclusions-These preliminary results showed that strain and shear wave elastography had similar diagnostic performance. The addition of strain and shear wave elastography to B-mode US improved diagnostic performance. The combination of strain and shear wave elastography results in a higher diagnostic yield than each individual elastographic modality.Key Words-breast; diagnostic performance; elastography; shear wave elastography; strain elastography U ltrasound (US) elastography is a noninvasive technique that measures tissue stiffness.1 It is useful for differentiating benign from malignant tumors in the breast.

Comparison of strain and shear wave elastography for qualitative and quantitative assessment of breast masses in the same population

“…Little published data pertaining to the direct comparison of diagnostic performance between strain and shear wave elastography in the same patients exists 11 , 12 , 14 . In this study, the difference in diagnostic performance was not significant when comparing conventional plus strain images and conventional plus shear wave images.…”

“…Few previous studies have compared strain and elasticity ratios, as determined by strain and shear wave elastography, of benign and malignant breast tumours in the same patients 11 , 12 . This study found the mean strain ratio and elasticity ratios to be significantly different between benign and malignant lesions in both strain elastography and shear wave elastography.…”

“…Many studies have shown that combining one of these two elastographic techniques with conventional ultrasonography improves differentiation between benign and malignant breast masses 2 – 4 , 9 . However, direct comparison of both types of elastography in the same population is relatively rare 10 – 12 ; to the best of our knowledge, few studies have compared the strain and elasticity ratios achieved with these techniques 11 , 12 . Additionally, regarding scoring colour-scale images obtained by strain and shear wave elastography, and the strain and elasticity ratios, cut-off values dividing benignity and malignancy differ among published studies 5 , 8 , 13 .…”

Shear wave versus strain elastography in the differentiation of benign and malignant breast lesions

“…However, these two studies used relatively different elastography techniques. Seo et al [12] reported similar diagnostic performances for both SWE and SE. In their study, the sensitivity of SR (95%) was higher than the mean elasticity (85%), and the specificity of the mean elasticity (96%) was higher than the SR (84%); however, the difference was not statistically significant.…”

“…There are limited studies in the current literature investigating whether SWE or SE is more reliable in differentiating malignant and benign breast lesions [12][13][14][15]. The present study aimed to assess and compare the diagnostic efficacy of SWE and SE for the differentiation of benign and malignant breast lesions by applying both techniques on the same breast lesions.…”