Diagnostic value of ultrasound in thyroid nodules with Hashimoto′s thyroiditis background

Objective To assess the value of ultrasound(US) in differentiating benign from malignant thyroid nodules with Hashimoto′s thyroiditis(HT) background.Methods A total of 172 thyroid nodules(116 benign nodules,56 malignant nodules) with Hashimoto′s thyroiditis background were included in this study.The sonographic characteristics of nodules were investigated,including type of thyroid essence echogenicity,number of nodule,size of nodule,morphology,border,echo type,homogeneity of internal echo,acoustic halo,calcification,posterior echo attenuation and blood supply.Results Among 172 nodules with Hashimoto′s thyroiditis background,67.4%(116/172) were benign(65 pseudonodularity,47 nodular hyperplasia or follicular adenoma,3 fibrosis,1 lymphoepithelial cyst),and 32.6%(56/172) were malignant(56 papillary carcinoma).Malignant nodules were more likely to be solitary(64.3% vs 40.5%),hypoechoic(92.9% vs 50.9%),irregular(60.7% vs 26.7%),obscure boundary(73.2% vs 27.6%),and aniso-internal echo(92.9% vs 38.8%).Calcification including microcalcification(58.9% vs 16.4%)and posterior echo attenuation(46.4% vs 19.0%)were more common among malignant nodules.Benign nodules were more likely to be multiple(54.3% vs 17.9%),hyperechoic(29.3% vs 0),having a halo(12.1% vs 0),and lacking calcifications(62.9% vs 19.6%).The background echogenicity of thyroid essence had some differences between malignant and benign nodules.The benign and malignant nodules were all of hypovascularity in color Doppler sonography.Conclusions Sonographic features of benign and malignant nodules with Hashimoto′s thyroiditis background are different in general,and gray scale ultrasound is good enough for the differentiation of benign from malignant nodules with Hashimoto′s thyroiditis background.