低剂量CT灌注联合影像组学评估非小细胞肺癌的纵隔淋巴转移

目的:探究基于低放射剂量CT灌注影像提取CT灌注参数以及影像组学参数联合评估非小细胞肺癌(NSCLC)纵隔淋巴转移的效能.方法:纳入2017年3月-2020年5月经病理证实为纵隔淋巴转移的NSCLC患者以及非纵隔淋巴转移的NSCLC患者,所有患者于术前行低剂量CT灌注扫描.术中系统性清扫患者N1及N2站淋巴结,并取肿瘤...

Low-dose CT perfusion combined with radiomics in evaluation of mediastinal lymphatic metastasis of non-small cell lung cancer

Objective:The purpose of this study was to explore the predictive value of perfusion parameters of low radiation dose CT perfusion combined with radiomics parameters extracted from the images of CT perfusion to evaluate mediastinal lymphatic metastasis of non-small cell lung cancer.Methods:Patients with pathologically confirmed mediastinal lymphatic metastasis of non-small cell lung cancer and with non-mediastinal lymphatic metastasis were recruited in our study from March 2018 to May 2020.All patients underwent low-dose CT perfusion scan before surgery.During the operation,the lymph nodes at N1 and N2 were systematically removed.The tumor tissues and lymph nodes were taken for microvessel density immunohistochemical tests and pathological examinations.According to the principle of stratification and randomization,all patients were divided into training group and testing group at a ratio of 7:3.Radiologists with more than 5~10 years of experience segmented the tumor region of interest(ROI)based on CT images and extracted CT perfusion parameters:BF,BV,MTT,PMB,and also 396 radiomics parameters.Based on the radiomics characteristics of the training group,LASSO(Least absolute shrinkage and selection operator)was used to construct the Radscore.A multiple logistic regression model,combined with Radscore and CT perfusion parameters,was built to evaluate the possibility of mediastinal metastasis.Results:After feature dimensionality reduction,Radscore,choose penalty coefficient log(λ)=0.867,was built by 7 radomics parameters.Radscore was of good diagnostic performance in evaluating mediastinal lymphocyte metastasis in the training group and test group(0.840 vs.0.841);MTT and BV were statistically different in the training group between mediastinal metastasis and non-mediastinal metastasis.The diagnostic performance in the training group and test group was higher than that of random diagnosis[(0.687 vs 0.698)(0.672 vs 0.698)].The diagnostic efficiency of the combined model was higher than Radscore,BV,and MTT in the training set(P=0.378,0.014,0.010),and lower than Radscore in the test set,but higher than BV and MTT(P=0.563,0.631,0.093).The statistical results of the combined model Hosmer-Lemeshow show that there was no significant difference between the model and the actual observation(P>0.05).Conclusion:CT perfusion parameters radiomics can be used to assess the mediastinal lymph node metastasis in patients with non-small cell lung cancer.At the same time,CT perfusion parameters and radiomics can be combined to construct a combined model to evaluate mediastinal lymph node metastasis.