Li Lin, Cheng Sai-Nan, Zhao Yan-Feng, Wang Xiao-Yi, Luo De-Hong, Wang Yong
Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
Department of Ultrasonography, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
J Thorac Dis. 2019 Dec;11(12):5032-5041. doi: 10.21037/jtd.2019.12.45.
Dual-energy computed tomography (DECT) imaging can generate iodine-based material decomposition (MD) images and spectral HU curve. This study aimed to investigate the diagnostic accuracy of single-source dual-energy CT (DECT) and ultrasonography (US) for detecting lateral cervical lymph node metastases of papillary thyroid carcinoma (PTC).
Thirty patients with PTC were enrolled in the study and underwent DECT and US examination before thyroidectomy and cervical lymph node dissection. The spectral parameters included iodine concentration (IC), normalized iodine concentration (NIC) and slope (λ) of lymph nodes. The CT morphological parameters included maximal short diameter, shape, margin, calcification and cystic degeneration of lymph nodes. The US morphological parameters included maximal short diameter, calcification and cystic degeneration of lymph nodes. The diagnostic value of every single spectral parameter, combined gemstone spectral image (GSI) parameters, CT morphological parameters and US morphological parameters between metastatic and non-metastatic lymph nodes were statistically compared. Receiver operating characteristic (ROC) curves, sensitivity, and specificity were used to determine the diagnostic value.
Ninety-nine lymph nodes from thirty patients were pathologically confirmed. Among them, 70 (70.7%) were metastatic. For single GSI parameters, ROC analysis showed that the area under the curve (AUC) for IC was the highest (AUC =0.937) but the difference was not statistically significant when compared with NIC or slope (λ) (P>0.05). The optimal diagnostic threshold for IC was 2.56 mg/mL, with a sensitivity, specificity and accuracy of 87.1%, 93.1%, and 88.9%, respectively. The AUC for combined GSI parameter (AUC =0.942) was higher compared with the US morphological parameters (AUC =0.771, P<0.001), with a sensitivity, specificity, and accuracy of 92.9%, 86.2%, and 90.9%, respectively. However AUC did not differ significantly among combined GSI parameters, combined CT morphological parameters and a single application for spectral CT parameters IC (P>0.05).
Combined GSI parameters showed better diagnostic accuracy in lateral cervical lymph node metastasis of PTC compared with that of combined US morphological parameters. IC alone showed excellent diagnostic stability and could be performed easily.
双能计算机断层扫描（DECT）成像可生成基于碘的物质分解（MD）图像和光谱HU曲线。本研究旨在探讨单源双能CT（DECT）和超声检查（US）对检测甲状腺乳头状癌（PTC）颈部侧方淋巴结转移的诊断准确性。
30例PTC患者纳入本研究，在甲状腺切除和颈部淋巴结清扫术前接受DECT和US检查。光谱参数包括淋巴结的碘浓度（IC）、归一化碘浓度（NIC）和斜率（λ）。CT形态学参数包括淋巴结的最大短径、形态、边缘、钙化和囊性变。US形态学参数包括淋巴结的最大短径、钙化和囊性变。对转移性和非转移性淋巴结之间的每个单一光谱参数、联合宝石光谱图像（GSI）参数、CT形态学参数和US形态学参数的诊断价值进行统计学比较。采用受试者操作特征（ROC）曲线、敏感性和特异性来确定诊断价值。
30例患者的99个淋巴结经病理证实。其中，70个（70.7%）为转移性。对于单一GSI参数，ROC分析显示IC的曲线下面积（AUC）最高（AUC =0.937），但与NIC或斜率（λ）相比差异无统计学意义（P>0.05）。IC的最佳诊断阈值为2.56 mg/mL，敏感性、特异性和准确性分别为87.1%、93.1%和88.9%。联合GSI参数的AUC（AUC =0.942）高于US形态学参数（AUC =0.771，P<0.001），敏感性、特异性和准确性分别为92.9%、86.2%和90.9%。然而，联合GSI参数、联合CT形态学参数和光谱CT参数IC的单一应用之间的AUC差异无统计学意义（P>0.05）。
与联合US形态学参数相比，联合GSI参数在PTC颈部侧方淋巴结转移中显示出更好的诊断准确性。单独的IC显示出优异的诊断稳定性且易于操作。
