Diagnostic Value of Contrast-enhanced Ultrasound in Extrathyroidal Extension of Papillary Thyroid Carcinoma

Abstract

Objective To evaluate the diagnostic value of contrast-enhanced ultrasound(CEUS)in thyroid extrathyroidal extension(ETE)of papillary thyroid carcinoma(PTC).Methods Totally 172 PTC patients(184 thyroid nodules)were examined by conventional ultrasound(US)and CEUS before operation.Sonographic features of thyroid nodules and the relationship between nodules and thyroid capsule were retrospectively evaluated.The diagnostic efficacy of these two methods for ETE was compared,and the effect of nodule enhancement level on the diagnosis of ETE was analyzed.Results The sensitivity,specificity,and accuracy of CEUS were 78.9%,89.4% and 84.2% in diagnosing ETE,while those of US were 60.0%,86.2%,and 73.4%,respectively.Among them,the sensitivity(P=0.000)and accuracy(P=0.009)of CEUS in diagnosing ETE were significantly higher than those of US,but there was no statistically significant difference in specificity(P=0.375).The area under the receiver operator characteristic curve of CEUS(0.84)was significantly larger than that of US(0.73)(Z=2.24,P=0.01).The diagnostic value of CEUS in ETE was related to the enhancement level of nodules.The sensitivity,specificity,and accuracy of CEUS in the diagnosis of ETE were highest in hypo-enhanced nodules,followed by hyper-enhanced nodules and the iso-enhanced nodules.Conclusion CEUS has higher performance than US in detecting ETC of PTC.