增强CT的形态学特征在预测结直肠癌淋巴结转移中的价值研究

To Study the Value of Morphologic Features in the Prediction of Lymph Node Metastasis of Colonrectal Cancer Base on Enhacement CT

目的研究结直肠癌周围淋巴结的形态学特点在预测其是否有转移中的价值,并将其与传统CT淋巴结转移标准进行比较。方法回顾性研究一共纳入的236例结直肠癌患者资料,所有患者均未行术前新辅助放化疗。由两位高年资主治医师在增强扫描门静脉期独立对淋巴结的影像学特点进行判读。淋巴结转移的形态学标准需满足以下任意一个条件:(1)强化不均匀;(2)边界不规则。传统标准需满足以下任意一个条件:(1)短径>10 mm;(2)淋巴回流区域3个或3个以上簇状分布淋巴结。用Kappa值来评价观察者间的一致性。计算CT形态学标准和传统标准在预测淋巴结转移中的敏感性、特异性、准确性、阳性预测值、阴性预测值、ROC曲线下面积(AUC),并用Delong检验来评价各自AUC的大小。结果236例结直肠癌中,其中104例有淋巴结转移,132例无淋巴结转移。两位观察者在形态学标准和传统标准上的一致性Kappa值分别为0.891和0.820。观察者A用形态学标准预测淋巴结转移的敏感性、特异性、准确性、阳性预测值、阴性预测值分别为47.1%、95.5%、78.4%、89.1%、69.6%,传统标准为60.6%、68.2%、64.8%、60.0%、68.7%;观察者B依次为46.2%、97.0%、74.6%、92.3%、69.6%和61.5%、68.2%、65.3%、60.4%、69.2%。Delong检验表明形态学标准比传统标准有更高的AUC值(观察者A:0.713 vs 0.644,P=0.031;观察者B:0.716 vs 0.649,P=0.027)。结论形态学特征是预测结直肠癌淋巴结转移的特异性指标,与传统标准相比,具有更高的特异性、AUC、准确性和阳性预测值和类似的阴性预测值,但是敏感性有所下降。

Objective To evaluate the value of morphologic features to predict lymph node(LN)metastasis of patients with colonrectal cancer(CRC),and to compare these features with the widely accepted traditional criteria.Methods This retrospective study consisted 236 patients diagnosed with CRCs and none of them underwent preoperative chemotherapy or radiotherapy.The morphologic features and traditional criteria were independently assessed by two senior attending physicians in the portal phase of enhanced scanning.Morphologic features need to meet any of the following conditions:LNs with heterogeneous enhancement pattern or irregular border.Traditional criteria need to meet any one of the following conditions:short-axis diameter above 10 mm or acluster of more than three nodes along the locoregional vascular pedicle.The inter-reader agreement was evaluated with Kappa value.Sensitivity,specificity,accuracy,positive predictive value(PPV),negative predictive value(NPV),AUC(area under the ROC curve)of morphologic features and traditional criteria were calculated,and the AUCs were compared using Delong test.Results Of the 236 CRCs,104 were LN metastases positive and 132 were negative.The Kappa value was 0.891 and 0.820 for the morphologic features and traditional criteria.For reader A,the sensitivity,specificity,accuracy,PPV and NPV was 0.471,0.955,0.784,0.891,0.696 for morphologic features,and 0.606,0.682,0.648,0.600,0.687 for traditional criteria.For reader B,they are 0.462,0.970,0.746,0.923,0.696 for morphologic features and 0.615,0.682,0.653,0.604,0.692 for traditional criteria.And the morphologic features have higher AUC than the traditional criteria(0.713 vs 0.644,P=0.031 for reader A and 0.716 vs 0.649,P=0.027 for reader B).Conclusion Morphological features are specific indicators for predicting lymph node metastasis in colorectal cancer.Compared with the traditional criteria,they have higher specificity,AUC,accuracy and positive predictive value,and comparable negative predictive value,but reduced sensitivity.