Clinical value of relative quantification ultrasound elastography in characterizing breast tumors

ObjectivesTo evaluate ultrasound elastography (USE) using strain ratio (SR), a relative quantification approach for breast lesions characterization.MethodsOne hundred forty-seven consecutive patients with a total of 156 breast lesions underwent USE. Technical accuracy was assessed automatically. For SR evaluation a rounded ROI was depicted inside fat (F), glandular tissue (G) and inside the lesion (L), preferably at the same depth. R1, mean value of the G and F ratio, stands for in background tissue composition elasticity. R2; mean value of L/F stands for in lesion elasticity, both evaluated in arbitrary unit (au). Two-years follow-up and pathology results were standard of reference. Mann–Whitney test, ROC analysis and Chi-square with Yates correction were used.ResultsWith the exception of 27 cysts, 17 malignant and 112 benign lesions were found. R1 values were 1.6 ± 0.7 au and 1.2 ± 0.9 au (p = 0.015 NS); R2 values were 6.1 ± 2.5 au and 1.9 ± 1.3 au (p < 0.001) for malignant and benign lesions, respectively. A threshold of 3.3 au showed a sensitivity and specificity of 88% and 87%, respectively with an AUC of 93%. Fifteen false positive and two false negative were detected.ConclusionRelative quantification of ultrasound elastography allows to find high levels of diagnostic accuracy in characterizing breast tumors above all in downgrading BI-RADS 3 and 4 lesions.