Differential Diagnostic Value Of Multi-slice Spiral Computed Tomography On Analyzing The Pure Ground Glass Nodules Of Preinvasive Lesion And Invasive Lesion

Objective:To discuss the diagnostic value of characteristics of computed tomographic(CT)image and clinical features between preinvasive lesion(atypical adenomatous hyperplasia,AAH,adenocarcinoma in situ,AIS)and invasive lesion(minimally invasive adenocarcinoma,MIA,invasive lung adenocarcinomas,ILA)which appearing pure ground glass nodules.Try to investigate the differential diagnosis value of pure ground-glass opacity nodules' s uniformity between preinvasive lesion and invasive lesion by quantitative analysis.Materials and Methods:To retrospective investigate the characteristics of CT images and clinical features of 80 p GGNs identified on CT scans from September 2014 to December 2016 at the first hospital of Jilin University.All lesions were resected and confirmed by pathology.The content of evaluation including lesion location,size,density,margin(smooth,lobulation,spiculation),tumor-lung interface(clear or unclear),internal characteristics(air bronchogram,bubble sign,air-containing space),uniformity,pleural indentation,gender,age and smoking history.The average CT attenuation(HU)and standard deviation was measured by placing a region of interest(ROI)in three different sites within the nodule barring the vessels and bronchioles.Using the relative value of average coefficient of variation[(standard deviation/mean)× 100% ] of three ROI within lesion represents the uniformity.The lesion size,uniformity,density and age were compared with pathological types using Independent t test.Gender of patients,lesion location and the characteristic of CT images were compared with pathological types using 2x test.A value of P less than 0.05 was considered to indicate a statistically significant difference.The size and uniformity of preinvasive and invasive lesions were assessed using ROC curves.Results:Among the 80 p GGNs,16 were preinvasive lesion(6 were AAH,10 were AIS)and 64 were invasive lesion(29 were MIA,35 were ILA).There were no significant differences in gender,age,lesion location and bubble sign between preinvasive lesion and invasive lesion.There were statistically significant differences between lesion size,uniformity,density,lobulation,spiculation,tumor-lung interface,air bronchogram and pleural indentation(P=0.001,0.001,0.01,0.033,0.034,0.029,0.041,0.042,respectively).The ROC curve showed that when consider the diameter of lesion 10.5mm as the optimal cut-off,the area under the ROC curve(AUC)is 0.770,sensitivity and specificity is 81.3 %,71.9 %,respectively;The optimal cut-off value for lesion uniformity in differentiating preinvasive lesions from invasive lesions was 0.085,the AUC is 0.785,with a sensitivity of 81.3%,a specificity of 75%.Conclusion:The size of lesion,the characteristics of CT images(uniformity,density,lobulation,spiculation,tumor-lung interface,air bronchogram and pleural indentation)have the differential diagnostic value between preinvasive lesion and invasive lesion.The quantitative analysis of p GGN uniformity provides a new method of objective analysis.