Natural Progression of Ground-glass Nodules after Curative Resection for Non-small Cell Lung Cancer

Background: This retrospective study investigated the natural course of synchronous groundglass nodules (GGNs) that remained after curative resection for non-small-cell lung cancer (NSCLC). Methods: Prospectively collected retrospective data were reviewed concerning 2,276 patients who underwent curative resection for NSCLC between 2008 and 2017. High-resolution computed tomography or thin-section computed tomography data of 82 patients were included in the study. Growth in size was considered the most valuable outcome, and patients were grouped according to GGN size change. Patient demographic data (e.g., age, sex, and smoking history), perioperative data (e.g., GGN characteristics, histopathology and pathological stage of the resected tumours), and other medical history were evaluated in a risk factor analysis concerning GGN size change. Results: The median duration of follow-up was 36.0 months (interquartile range, 23.0-59.3 months). GGN size decreased in 6 patients (7.3%), was stationary in 43 patients (52.4%), and increased in 33 patients (40.2%). In univariate analysis, male sex, the GGN size on initial CT, part-solid GGN and smoking history (>= 10 pack-years) were significant risk factors. Among them, multivariate analysis revealed that lager GGN size, part-solid GGN and smoking history were independent risk factors. Conclusion: During follow-up, 40.2% of GGNs increased in size, emphasising that patients with larger GGNs, part-solid GGN or with a smoking history should be observed.