Contrast-Enhanced Ultrasound in the Differential Diagnosis of Primary Thyroid Lymphoma and Nodular Hashimoto's Thyroiditis in a Background of Heterogeneous Parenchyma.

Lulu Yang,Can Yue,Buyun Ma,Yan Luo,Xianglan Zhu,Haina Zhao,Yushuang He

doi:10.3389/fonc.2020.597975

Abstract

ObjectiveTo investigate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the differentiation of primary thyroid lymphoma (PTL) and nodular Hashimoto’s thyroiditis (NHT) in patients with background of heterogeneous diffuse Hashimoto’s thyroiditis (HT).MethodsSixty HT patients with 64 thyroid nodules (31 PTL and 33 NHT) who had undergone CEUS examination were included in this study. With histopathological results as the reference, we evaluated the imaging features of each nodule on both conventional ultrasonography (US) and CEUS. Quantitative CEUS parameters including peak intensity (PI), time to peak (TTP), and area under the time–intensity curve (AUC) were gathered in the nodule and background parenchyma. The ratio indexes of theses parameters were calculated by the ratio of the lesion and the corresponding thyroid parenchyma. Logistic regression and receiver operating characteristic (ROC) curves analyses of valuable US indicators were further preformed to evaluate the diagnostic capability of CEUS in discrimination of PTL and NHT.ResultsAmong all the observed US imaging features and CEUS parameters, 10 indicators showed significant differences between PTL and NHT (all P < 0.05). All the significant indicators were ranked according to the odds ratios (ORs). Eight of them were CEUS associated including imaging features of enhancement pattern, degree, homogeneity, and quantification parameters of PI, AUC, ratios of PI, AUC, and TTP, while indicators on conventional US, including vascularity and size ranked the last two with ORs less than 3. The five single CEUS parameters showed good diagnostic performance in diagnosis of PTL with areas under ROC curves of 0.72–0.83 and accuracies of 70.3–75.0%. The combination of CEUS imaging features and the ratios of PI, AUC, and TTP demonstrated excellent diagnostic efficiency and achieved area under ROC curve of 0.92, which was significantly higher than any of the five single parameters (all P < 0.05), with a sensitivity of 83.9%, specificity of 87.9%, and accuracy of 85.9%.ConclusionsCEUS is an efficient diagnostic tool in the differential diagnosis of PTL and NHT for patients with diffuse HT. Conjoint analysis of CEUS imaging features and quantification parameters could improve the diagnostic values.

Highlights

Hashimoto’s thyroiditis (HT) is a common autoimmune thyroid disease and affects at least 2% of all females [1]
72 patients who were clinically diagnosed with HT and whose nodules were histopathologically confirmed as HT or lymphoma were enrolled in this study
The combination of three ratios of peak intensity (PI), time to peak (TTP), and area under the curve (AUC) demonstrated Areas under the ROC curves (AUROCs) of 0.86, which was significantly higher than that of independent indicators of AUC and TTP ratio, with AUROCs of 0.72 and 0.74, respectively

Summary

Introduction

Hashimoto’s thyroiditis (HT) is a common autoimmune thyroid disease and affects at least 2% of all females [1]. It is characterized by the presence of serum anti-thryoglobulin (TgAb) and antiperoxidase (TPOAb) antibodies, sometimes accompanied with hypothyroidism. Patients with HT are demonstrated at 40–80 times greater risk for developing primary thyroid lymphoma (PTL) compared to those without thyroiditis [2, 3]. PTL is an uncommon cause of malignancy, which accounts for 5% of all thyroid malignances and occurs in less than 3% of non-Hodgkin’s extra-nodal lymphoma [6, 7], it deserves more attention because therapeutic strategies of PTL is different from other kinds of thyroid neoplasm. Diagnosis and appropriate treatment could avoid extensive surgery and improve prognosis [8, 9]

Methods

Results

Conclusion