Objectives: To evaluate the diagnostic performance of two-dimensional shear wave elastography (2D-SWE) in distinguishing malignant from benign thyroid nodules.
Methods: A total of 331 focal thyroid nodules from 271 patients scheduled for fine-needle aspiration or thyroid surgery were included. After a routine conventional ultrasound evaluation, 2D-SWE examinations were performed to obtain 2D-SWE measurements on a colour-coded mapping, which were then correlated with pathology results.
Results: A total of 230 nodules were benign and 101 were malignant on pathology. The areas under the receiver operating characteristic curve (AUC) of mean and minimum values in the largest region of interest (ROI) over the whole nodule, and mean, maximum and minimum values in 2-mm ROI over the stiffest area of the nodule were 0.794, 0.673, 0.808, 0.805 and 0.799, respectively. The most accurate cut-off value, 39.3 kPa, for mean value in a 2-mm ROI achieved 66.3 % sensitivity and 84.4 % specificity to discriminate malignancy. Nodule size correlated with 2D-SWE value for malignant nodules (P < 0.01). In the group of nodules ≤10 mm, the AUC was 0.730, while it was 0.883 in nodules sized 11-30 mm and 0.821 in nodules >30 mm.
Conclusion: 2D-SWE is a promising diagnostic tool for discriminating malignant thyroid nodules, although the performance for nodules ≤10 mm is not satisfactory.