Analysis of histopathologic subtypes and CT characteristics of lung adenocarcinomas presenting as pure ground-glass nodule around 1-3 cm in maximal diameter

Objective To evaluate the correlations between CT features and histopathologic subtypes of lung adenocarcinomas presenting as pure ground-glass nodules (pGGN) around 1-3 cm in maximal diameter. Methods CT appearances, pathology and clinical data of 192 patients (192 lesions). To be divided three classes, including 31 preinvasive lesions 4 atypical adenomatous hyperplasia, 27 adenocarcinoma in situ, 71 minimally invasive adenocarcinoma (MIA) and 90 invasive pulmonary adenocarcinoma (IPA) who underwent curative resection of lung adenocarcinomas presenting as 1 ≤ pGGN ≤ 3 cm in diameter from October, 2013 to December, 2016 were retrospectively analyzed in our hospital. Via SPSS 22.0 statistics software, age and gender of patients, lesion size, density, lesion location, shape, presence of bubble-like sign, air bronchogram, pleural tag, vessel changes, margin, tumor-lung interface and uniformity were compared among histopathologic subtypes. Results There were no significant differences among histopathologic subtypes in terms of gender of patients, lesion location, tumor-lung interface, and shape. There were significant differences among lesion preinvasion, MIA and IPA in terms of age, lesion size and density. There were statistically significant differences among histopathologic subtypes in terms of vessel changes, presence of bubble-like sign, air bronchogram and pleural tag. With the increasing degree of invasiveness, the homogeneous uniformity of lesions tend to lessen; Compared with preinvasive lesions and MIA, IPA was more inclined to present as speculated or speculated plus lobulated. There were statistically significant differences among histopathologic subtypes in terms of uniformity and margin. The optimal cutoff value of lesion density for differentiating preinvasive lesions from invasive lesions was -549.35 Hu (sensitivity, 74.50%; specificity, 71.00%). Conclusion Age of patients, lesion size, density, margin, vessel changes, uniformity, presence of bubble-like sign, air bronchogram and pleural tag may indicate the invasiveness of lung adenocarcinoma presenting as pGGNs of 1 to 3 cm in diameter.