The Value Of CT Features On The Differential Diagnosis Of Pulmonary Subsolid Nodules And The Invasive Degree Prediction In Pulmonary Adenocarcinoma

Objective According to the latest pathological classification of adenocarcinoma in 2011,quantitative and qualitative CT image features of nodules were used to evaluate the value of imaging parameters in the differentiation of benign,malignant,and malignant degree of subsolid nodules and low-risk subsolid nodules of inert growth in the benign group,AAH / AIS / MIA group,invasive adenocarcinoma group and 2-year followed up without change group.Materials and Methods The study selected 152 subsolid nodules,of which 106 were resected surgically,the rest 46 were followed up for 2 years without change.The resected nodules were divided into benign group and malignant group according to pathology.The malignant group was further divided into AAH / AIS / MIA group and invasive adenocarcinoma group,according to malignant degree and prognosis.The forty-six nodules that remained unchanged for 2 years entered 2-year followed up without change group.Measured qualitative and quantitative indicators of CT signs of these subsolid nodules: nodule type,shape,tumor interface,margin,vacuole,air bronchus sign,pleural retraction,pulmonary vascular abnormality,multiplicity,location by lobe,peripheral distribution,long diameter,short diameter,height,average CT value(HU)of ROI and its standard deviation(SD),volume,volume of solid component,percentage of volume of solid component,average CT value,mass.The qualitative and quantitative variables of CT features of these subsolid nodules were analyzed using the ?2 test or Fisher exact test(qualitative variables),nonparametric test Mann-Whitney U test(quantitative variables)and the statistically significant variables were further enrolled into binary logistic regression analysis.A P value less than 0.05 was regarded as statistically significance.Results 1.There were statistically significant differences in the tumor interface,lobulation,pleural traction,air bronchus sign,pulmonary vascular abnormality,nodule long diameter and the standard deviation of average CT value of ROI between benign group and malignant group(P < 0.05).2.There was a significant difference in the air bronchus sign,the volume of solid component between benign group and AAH / AIS / MIA group(P <0.05).3.There were significant differences in the nodule type,pleural traction,long diameter,short diameter,volume,average CT value,the volume of solid component and the percentage of volume of solid components and mass between AAH / AIS / MIA group and invasive adenocarcinoma group(P<0.05).4.The results of binary logistic analysis showed a clear tumor interface,air bronchus sign and pulmonary vascular abnormalities were important indicators of malignant nodules,the risk ratio were 38.1,7.9 and 7.2,respectively.The greater percentage of volume of solid component was an important indicator to differentiate invasive adenocarcinoma from AAH / AIS / MIA group,the risk ratio was 1.04.5.There was a statistically significant difference in the nodular type,shape,smooth margin,spiculated margin,pleural traction,air bronchogram,pulmonary vascular abnormality,the long diameter,short diameter,height,average CT value of ROI,SD of average CT value of ROI,volume,average CT value,volume of solid component,the percentage of volume of solid component,mass between the AAH / AIS / MIA group and 2-year followed-up without change group.(P<0.05).6.There was a statistically significant difference in the nodular type,shape,smooth margin,lobulation,speculated margin,vacuole,air bronchogram,pleural traction,pulmonary vascular abnormality,the long diameter,short diameter,height,average CT value of ROI,SD of average CT value of ROI,volume,average CT value,volume of solid component,the percentage of volume of solid component,mass between the invasive adenocarcinoma group and 2-year followed-up without change group.(P<0.05).Conclusion Subsolid nodules are more likely to be malignant when there is a clear tumor interface,air bronchus sign or pulmonary vascular abnormality.The higher percentage for the volume of solid components in malignant nodules indicates higher invasiveness.The 2-year followed-up without change nodules compared with AAH/AIS/MIA or invasive adenocarcinoma were more likely to be ground-glass nodules,round or oval,smooth margin,no speculated margin,less pleural traction,air bronchogram,pulmonary vascular abnormality,smaller diameter,smaller volume,lower CT value,smaller solid component and mass.Meanwhile the 2-year followed-up without change nodules compared with invasive adenocarcinoma were more likely to be no lobulation,less vacuole.