Impact of ground glass opacity in a three-dimensional analysis for pathological findings and prognosis in stage IA pure solid lung cancer

BACKGROUND: We investigated whether a three-dimensional (3D) analysis could correct the discrepancy between conventional computed tomography findings and pathological findings and contribute to prognostic stratification in early pure solid lung cancer. METHODS: A total of 370 patients with two-dimensional (2D) pure solid, clinical stage IA non-small cell lung cancer (NSCLC) who underwent complete resection at our hospital between January 2010 and March 2021 were included in the present study. We classified the patients into the 3D solid group and the 3D ground glass opacity (GGO) group according to the consolidation volume/tumor volume ratio (C/T volume ratio) measured using a Synapse Vincent 3D analysis workstation, and compared the pathological findings and prognosis between the two groups. RESULTS: There were 142 (38.4%) patients in the 3D GGO group. Lepidic lesions were significantly more frequent in the 3D GGO group (27.6% vs. 59.2%, P<0.001). Lymphatic invasion, vascular invasion and lymph node metastasis were significantly more frequent in the 3D solid group (52.2% vs. 27.5%, P<0.001; 67.5% vs. 43.0%, P<0.001; 22.3% vs. 11.2%, P=0.04). A Cox proportional hazards multivariate analysis for overall survival (OS) and recurrence-free survival (RFS) showed that 3D solid was an independent poor prognostic factor [hazard ratio (HR): 1.981, P=0.02; HR: 1.815, P=0.02]. Kaplan-Meier curves for 5-year OS (74.1% vs. 87.8%, P<0.001) and 5-year RFS (65.6% vs. 84.9%, P<0.001) showed significant differences between the two groups. CONCLUSIONS: The C/T volume ratio determined by a 3D analysis detects GGO and reflects the pathological findings, and further prognostic stratification is possible in early 2D pure solid lung cancer.