Diagnostic Value Of Spectrum CT Quantitative Parameters In Lymph Node Metastasis Of Non-small Cell Lung Cancer

Objective:To investigate the preliminary study of quantitative CT scan of non-small cell lung cancer with mediastinal lymph node metastasis.Methods:Fifty-five patients with pathologically diagnosed non-small cell lung cancer who underwent enhanced CT scan were prospectively analyzed.Among them,38 were male,22 were female,23 were squamous cell carcinoma and 37 were adenocarcinoma.According to this study,100,metastatic 65,non-metastatic 35.The spectral parameters of iodine(IC),iodine(NIC),water(WC),normalized water(NWC)and normalized water were measured respectively in lymph node metastasis and non-Spectral curve slope K and effective atomic number.The pathological parameters of different stages of metastatic lymph nodes in different pathological types of lung cancer were compared by using independent samples t-test,P <0.05 was statistically significant;between the metastatic and non-metastatic lymph nodes and the primary tumor,Spectral parameters were compared using paired t-test,P <0.05 was statistically significant.Two-phase spectral parameters between the metastasis group and the non-metastasis group were compared using independent samples t-test,P <0.05 was statistically significant.ROC curve analysis was performed on the spectral parameters with statistical difference between metastatic and non-metastasized lymph nodes.The optimal critical value of each parameter was determined by calculating Youden index(YI),and the value of using this threshold to diagnose the type of lung cancer Sensitivity,specificity,area under the curve(AUC)of less than 0.7 for the diagnosis of low performance,between 0.7 to 0.9 for the medium,more than 0.9 for the high,P <0.05 for the difference was statistically significant.Results:There were no significant differences in the spectral parameters between squamous cell carcinoma and adenocarcinoma with metastatic lymph nodes(P> 0.05).There were no significant differences in the spectral parameters between lymph node and primary tumor(P> 0.05)There were significant differences in IC value,NIC value,effective atomic number and energy spectrum slope between lymph node and primary tumor(P <0.05),but no significant difference between WC and NWC(P> 0.05)The values of IC value,NIC value,effective atomic number and energy spectrum curve in the group of lymph nodes were significantly lower than those in the non-metastasis group(P <0.05),while WC and NWC values were not statistically significant(P> 0.05).The ROC curve analysis of the statistically significant parameters above showed that the NIC value of the venous phase had the highest diagnostic efficacy.When the NIC was 0.44 mg / ml,the sensitivity of the mediastinal lymph node metastasis was 84.8% and the specificity was 82.9%,The area under the curve is 0.881.Conclusion: The quantitative parameters of spectrum CT have some clinical value in the preoperative evaluation of mediastinal lymph node metastasis of NSCLC,which is helpful for the preoperative identification of lymph node metastasis.