Gao Lu, Lu Xiaomei, Wen Qingyun, Hou Yang
Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China.
CT Clinical Science, Philips Healthcare, Shenyang, China.
Quant Imaging Med Surg. 2021 Jun;11(6):2622-2633. doi: 10.21037/qims-20-1045.
Lymph node (LN) metastasis is an important factor affecting the treatment of lung cancer. The purpose of this article was to investigate the benefits of dual-layer spectral detector computed tomography (SDCT) for the evaluation of metastatic LNs in lung cancer.
Data from 93 patients with lung cancer who underwent dual-phase enhanced scanning with SDCT were retrospectively analyzed. According to the pathological findings, 166 LNs were grouped as metastatic (n=80) or non-metastatic (n=86). LNs in station 4 (n=80) and station 7 (n=35) accounted for the majority of the LNs (approximately 69.23%). The short-axis diameter of the LN, arterial enhancement fraction (AEF), normalized iodine concentration (NIC), and the slope of the spectral Hounsfield unit curve (λ) during the arterial phase (AP) and venous phase (VP) were measured. The Mann-Whitney U test was used to statistically compare these quantitative parameters. Receiver operating characteristic (ROC) curves were plotted to identify the cutoff values, and decision curve analysis (DCA) was performed to determine the net benefit of each parameter. The diagnostic performance, obtained by combining the short-axis diameter with each of the above parameters, was also studied.
The short-axis LN diameter, AEF, NIC, and λ during the AP and VP all showed significant differences between the metastatic and non-metastatic groups (P<0.05). Of the parameters, the AEF had the greatest diagnostic efficiency for metastatic LNs [area under the ROC curve (AUC) =0.885] with a threshold of 86.40%. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and 95% confidence interval were 90.00%, 89.53%, 88.89%, 90.59%, and 0.830-0.944, respectively. When the quantitative parameters were combined with the short-axis diameter, the AUCs of the parameters, except the AEF, were significantly improved (P<0.05).
The iodine quantitative parameters from SDCT, such as the AEF, demonstrated high diagnostic performances in the differentiation of metastatic and non-metastatic LNs.
淋巴结转移是影响肺癌治疗的重要因素。本文旨在探讨双层光谱探测器计算机断层扫描（SDCT）在评估肺癌转移性淋巴结方面的优势。
回顾性分析93例行SDCT双期增强扫描的肺癌患者的数据。根据病理结果，166枚淋巴结被分为转移组（n = 80）和非转移组（n = 86）。第4组（n = 80）和第7组（n = 35）的淋巴结占大多数（约69.23%）。测量淋巴结的短轴直径、动脉期强化分数（AEF）、标准化碘浓度（NIC）以及动脉期（AP）和静脉期（VP）的光谱Hounsfield单位曲线斜率（λ）。采用Mann-Whitney U检验对这些定量参数进行统计学比较。绘制受试者操作特征（ROC）曲线以确定临界值，并进行决策曲线分析（DCA）以确定各参数的净效益。还研究了将短轴直径与上述各参数相结合所获得的诊断性能。
转移组和非转移组之间，淋巴结短轴直径、AP和VP期的AEF、NIC以及λ均存在显著差异（P < 0.05）。在这些参数中，AEF对转移性淋巴结的诊断效率最高[ROC曲线下面积（AUC） = 0.885]，阈值为86.40%。敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）和95%置信区间分别为90.00%、89.53%、88.89%、90.59%和0.830 - 0.944。当定量参数与短轴直径相结合时，除AEF外，其他参数的AUC均显著提高（P < 0.05）。
SDCT的碘定量参数，如AEF，在鉴别转移性和非转移性淋巴结方面具有较高的诊断性能。
