Ultrasound scoring in combination with ultrasound elastography for differentiating benign and malignant thyroid nodules.

OBJECTIVE: The aim of this study was to evaluate the value of ultrasound scores obtained by conventional ultrasonography and ultrasound elastography in the differentiation of benign and malignant thyroid nodules in Chinese patients.

METHODS: This study included 297 patients who were referred for surgery for compressive symptoms or suspicion of malignancy. Five hundred and twelve thyroid nodules were examined by ultrasonography. The final diagnosis was based on histological findings. A seven-point ultrasound scoring system based on conventional ultrasonography and a five-point scoring system based on ultrasound elastography were applied independently or in combination. The receiver operating characteristic (ROC) curves were graphed, and the areas under the curves (AUCs) were compared using the χ(2) -test.

RESULTS: Solid composition, hypo-echoic appearance, an irregular or blurred margin, an aspect ratio ≥1, intranodular blood flow and presence of microcalcifications were significant predictors of malignant thyroid nodules. The AUC (95% CI) was 0·9067 (0·8817-0·9318) for the ultrasound scores based on conventional ultrasonography and 0·9080 (0·8842-0·9317) for the elasticity scores. The combination of these two scoring systems provided good accuracy with an AUC (95% CI) of 0·9415 (0·9223-0·9606), which was significantly higher than that obtained with the conventional ultrasound scores (χ(2)  = 36·03, P < 0·001) or the elasticity scores (χ(2)  = 12·80, P < 0·001) individually. When we set the cut-point to ≥5, the sensitivity and specificity were 85·22% and 87·38%, respectively.

CONCLUSIONS: Elastography in combination with conventional ultrasonography is a promising imaging-based approach that can assist in the differential diagnosis of thyroid cancer.