Shear wave elastography combined with high-frequency ultrasound for predicting the presence of occult carcinoma contralateral to unilateral papillary thyroid cancer.

OBJECTIVE

To investigate the correlation between high-frequency ultrasound (US) signs and shear wave elastography (SWE) parameters of papillary thyroid carcinoma (PTC) in a unilateral lobe and the contralateral lobe occult PTC, and to evaluate the value of SWE in combination with high-frequency US in predicting contralateral occult carcinoma of the thyroid gland preoperatively, to provide clinicians with assistance in the selection of preoperative surgical approaches.

METHODS

We collected a total of 552 preoperatively diagnosed patients with unilateral thyroid carcinoma and postoperatively pathologically confirmed PTC. High-frequency US and SWE were performed before surgery. Based on the pathologic findings, they were divided into the contralateral occult PTC positive group and the negative group. To investigate the association between the ultrasonographic features of unilateral PTC and the presence of contralateral occult carcinoma by univariate and multivariate analyses, and comparing the accuracy of high-frequency US alone, SWE alone, and SWE combined with high-frequency US in predicting contralateral occult PTC.

RESULTS

Univariate analysis showed that the differences between the two groups of extrathyroidal extension (ETE), ipsilateral multifocality, the combination of Hashimoto's thyroiditis (HT), the combination of lymph node metastasis, and Emax and Emean values of the primary tumors were statistically significant (P < 0.05). The multifactorial binary logistic regression model showed that the differences between the two groups of extrathyroidal extension, ipsilateral multifocality, lymph node metastasis, HT and high Emax value were all independent predictors of contralateral occult PTC. The ROC curve analysis showed no statistically significant difference between high-frequency ultrasound and SWE in predicting the AUC of contralateral occult PTC (0.739 vs 0.699,P = 0.185). The AUC for predicting contralateral occult PTC using high-frequency US combined with SWE was significantly higher than the AUC predicted using high-frequency US and SWE alone (0.794 vs 0.739, P = 0.005; 0.794 vs 0.699,P < 0.001) CONCLUSION: SWE combined with high-frequency US improves the prediction of contralateral occult PTC, and the presence of contralateral occult PTC is more likely in the presence of extrathyroidal extension of a unilateral lobe lesion of the thyroid gland, ipsilateral multifocality, metastasis to cervical lymph nodes, high Emax, and the combination of HT.