Quantitative assessment of shear-wave ultrasound elastography in thyroid nodules: diagnostic performance for predicting malignancy

To evaluate the predictability of shear-wave ultrasound elastography (SWE) for thyroid malignancy and to compare the diagnostic performances of SWE and B-mode US. Retrospective review of 99 patients who underwent SWE before US-guided fine-needle aspiration of thyroid nodules was performed. SWE elasticity indices of the mean (E-mean ), maximum (E-max), and minimum (E-min) of nodules were measured. Diagnostic performance of SWE was compared with that of B-mode US. Among a total of 99 nodules, 21 were papillary thyroid carcinoma (PTC) and 78 were benign. E-mean, E-max, and E-min were significantly higher in PTCs than in benign nodules (P < 0.001). Sensitivity and specificity for predicting malignancy were 76.1 %, 64.1 % with E-max (65 kPa), 61.9 %, 76.1 % with E-min (53 kPa), and 66.6 %, 71.6 % with E-mean (62 kPa). Areas under the ROC curves (Az) of SWE values were not significantly different from those of US categories on B-mode US. However, combining E-mean and E-min with B-mode US of probably benign lesions improved the specificity (P = 0.02, 0.007) for predicting PTC. The quantitative parameter of SWE was significantly higher in PTC than in benign nodules, and combined use of quantitative SWE and B-mode US provided higher specificity for predicting malignancy. Quantitative shear-wave elastography (SWE) helps differentiate benign from malignant nodules SWE and conventional ultrasound have comparable diagnostic performance for predicting thyroid malignancy Combined quantitative SWE and B-mode ultrasound is highly specific for thyroid malignancy.