二维剪切波弹性定量成像在鉴别甲状腺微小癌及预测被膜侵犯中的应用价值

Diagnostic value of two-dimensional shear wave elastography in thyroid microcarcinoma and prediction of extrathyroidal extension

关键词:  甲状腺结节  剪切波弹性成像  甲状腺被膜侵犯  病理诊断

Key words:  thyroid nodule  shear wave elastography  extrathyroidal extension  pathologic diagnosis

摘要:

目的 探讨二维剪切波弹性成像（2D-SWE）定量参数在甲状腺微小良性结节与微小乳头状癌（PTMC）中的差异及其在预测PTMC被膜侵犯中的应用价值。方法 收集行细针穿刺（FNAB）或手术切除的63例患者的73枚甲状腺微小结节（最大径≤1 cm），二维高频超声观察并记录结节与甲状腺被膜的关系，2D-SWE测量并记录结节的SWE-E值（KPa）。以细胞或组织病理为金标准，将结节分为良性结节组和PTMC组，构建SWE-E的ROC曲线，评估2D-SWE鉴别甲状腺微小结节良恶性的能力。进一步将PTMC分为侵犯被膜组和未侵犯被膜组，构建SWE-E的ROC曲线，评估2D-SWE对PTMC被膜侵犯的预测价值。结果 PTMC的SWE-E值（78.54±22.56）KPa明显高于良性微小结节的SWE-E值（34.92±13.65）KPa，差异有统计学意义（P<0.01）。SWE-E诊断PTMC的最佳截断值为44.27 KPa，诊断的敏感性为96.1%，特异性为90.9%。二维高频超声预测被膜侵犯的敏感性为76.0%，特异性为84.6%。侵犯被膜组的SWE-E值（92.97±20.80）KPa明显高于未侵犯被膜组的SWE-E值（64.66±13.93）KPa，差异有统计学意义（P<0.01）。SWE-E预测被膜侵犯的最佳截断值为72.76 KPa，诊断的敏感性为96.0%，特异性为73.1%。结论 2D-SWE定量成像提供量化的组织硬度信息，在诊断PTMC中可作为常规二维高频超声的有力补充；2D-SWE定量成像对PTMC被膜侵犯具有良好的预测价值。

Abstract:

Objective To evaluate the diagnostic value of two-dimensional shear wave elastography (2D-SWE) for papillary thyroid microcarcinoma (PTMC) and to investigate its application in the prediction of extrathyroidal extension (ETE). Methods Sixty-three patients with 73 thyroid nodules (≤1 cm) were included in this study who received conventional grayscale ultrasound (US) and 2D-SWE before fine-needle aspiration or surgery. The relationship between malignant lesions and the thyroid capsule was observed by US. And Young's modulus value (KPa) was analyzed and recorded with 2D-SWE. The thyroid nodules were divided into benign nodule group and PTMC group according to the cytopathology and surgical pathology results. Receiver-operating characteristic (ROC) curve analysis was performed to assess the performance of 2D-SWE in diagnosing PTMC. The patients with PTMC were furhter divided into ETE group and non-ETE group according to the surgical pathology results. Conventional US findings were analyzed and compared between the ETE group and non-ETE group. ROC curve analysis was performed to assess the performance of 2D-SWE in predicting pathologic ETE. Results The value of SWE-E in PTMCs (78.54±22.56)KPa was significantly higher than that in benign nodules (34.92±13.65)KPa, and the difference was statistically significant (P<0.01). The optimal cut-off value of SWE-E for predicting malignancy was 44.27 KPa, with a sensitivity and specificity of 96.1% and 90.9%, respectively. The sensitivity and specificity of conventional US to predict pathologic ETE were 76.0% and 84.6%, respectively. The value of SWE-E in PTMC ETE group (92.97±20.80)KPa was significantly higher than that in non-ETE group (64.66±13.93)KPa, and the difference was statistically significant (P<0.01). The optimal cut-off value of SWE-E for predicting pathologic ETE was 72.76 KPa, with a sensitivity and specificity of 96.0% and 73.1% respectively. Conclusions 2D-SWE can be used as a powerful supplement to conventional grayscale US in diagnosing PTMC, providing quantitative stiffness information when conventional US cannot give a definite result. 2D-SWE has a good performance in predicting pathologic ETE in PTMC.