Differential Diagnosis Of MSCT In Ground-grass Nodule ?10mm

Objective:To analyze the imaging characteristics and differential diagnosis of MSCT(multi-slice spiral CT)in different pathological types of patients with ground-grass nodule(GGN)?10mm.Materials and Methods:Through the follow-up visit and pathological results,270 patients with GGN ?10mm confirmed from January 2016 to October 2017 in our hospital were reviewed.As the patients were pathologically proved,they were assigned to 65 benign cases and 205 malignant cases.According to the pathological types,the malignant patients were classified into atypical adenomatous hyperplasia(AAH)group(n=65),adenocarcinoma in situ(AIS)group(n=69)and minimally invasive adenocarcinoma(MIA)group(n=71).According to the scanning results,the MSCT signs in benign and malignant patients as well as the MSCT distribution,morphological characteristics and accompanied signs in different pathological types of patients with GGN?10mm were probed.Results:The female malignant patients were significantly more than female benign patients;except for the gender,there were no significant between-group difference in the patient's smoking history,positive symptoms and diseased region(P>0.05);for 270 GGN cases,63 cases were pathologically proven as pGGN(pure ground-grass nodule).None of pGGN case was occurred in the local fibrosis and pulmonary sclerosing hemangioma patients,which most of them were presented with AAH(30 cases).207 cases were proven as mGGN(mixed ground-grass nodule)of which 130 mGGN cases were occurred in the adenocarcinoma patients.Through the follow-up visit,the rate of removing the lesions was lowest.?The lesion forms(circular/quasi-circular,irregular),edge(spicule,lobulation),lung-tumor boundary(clear,vague),internal structure(solid,vacuole,air bronchogram),adjacent tissue changes(vessel convergence signs)in the malignant and benign lesions were significantly different(P<0.05);the lesion size and average CT value for three malignant groups were significantly different,which the GGN size in the MIA group was larger than AAH group and AIS group;the average CT value in the AAH group was higher than AIS group and MIA group(P<0.05);the rate of vague lung-tumor boundary and air bronchogram in the AAH group was lower than AIS group and MIA group(P<0.05);the detection rate of malignant lung tumor in the re-examination was significantly higher than that in the initial examination(P<0.05).Conclusion:The patients with GGN ?10mm shall be much concerned.The key characteristics of malignant GGN include the circular/quasi-circular form,clear lung-tumor boundary,lobulated and spicule edge,solid components,vacuole signs and vessel convergence signs.Meanwhile,the key characteristics of benign GGN include the irregular forms and vague lung-tumor boundary.