Study of Imaging Analysis for Distinguishing Alveolar Collapse From Invasive Lesions in Early‐Stage Lung Adenocarcinoma

Background Non‐invasive lung adenocarcinoma may occasionally contain solid benign components, presenting challenges for making an accurate diagnosis using CT (computed tomography). Therefore, we investigated whether a three‐dimensional (3D) volumetric analysis was more effective than CT in distinguishing the presence of invasive lesions in early‐stage lung adenocarcinoma. Materials and Methods We retrospectively classified 161 patients preoperatively diagnosed with clinical stage IA1 into two groups: the non‐invasive lesion group (50 patients) and the invasive lesion group (111 patients). We conducted a comparative analysis concerning the predictive performance of CT and a 3D volumetric analysis to identify invasive lesions. In addition, a histological review of the pre‐invasive lesion group was performed to assess the pathological characteristics of the solid component, as observed on preoperative CT. Results A univariate analysis demonstrated that the consolidation diameter, consolidation/tumor (C/T) ratio, consolidation volume, and three‐dimensional (3D)‐C/T ratio were significant predictors of the presence of invasive lesions. A multivariate analysis identified the consolidation volume as an independent predictor ( p = 0.045). Analyses of the receiver operating characteristics showed that the areas under the curve for the consolidation diameter, consolidation volume, C/T ratio, and 3D‐C/T ratio were 0.702, 0.634, 0.747, and 0.742, respectively. In addition, a histological review revealed alveolar collapse in 89.2% (25 of the 28) of the preinvasive lesion group. Conclusions Consolidation diameter, consolidation volume, and 3D‐C/T ratio are more reliable predictors for distinguishing alveolar collapse from invasive lesions than the C/T ratio in early‐stage lung adenocarcinoma.