The prognostic impact of tumor volume in patients with clinical stage IA non-small cell lung cancer

Introduction: Tumor volume promises to be an important factor for predicting the prognosis of patients with non- small cell lung cancer (NSCLC). Methods: A total of 255 patients who underwent curative surgical resection for clinical stage IA NSCLC were included. We performed semiautomated measurement of the whole tumor volume and the volume of the solid part (referred to as the solid part volume) from a volumetric analysis of chest three-dimensional computed tomography scans using the SYNAPSE VINCENT imaging software program (Fujifilm Medical, Tokyo, Japan). We evaluated the relationships among tumor size, tumor volume, and survival. Results: The mean whole tumor size, the ratio of the maximum diameter of consolidation to the maximum tumor diameter (CTR), the whole tumor volume, and the solid part volume were 20 mm (range 0-30 mm), 0.84 (range 0-1.0), 3080 mm³ (range 123-17509 mm³), and 2032 mm³ (0- 12466 mm³), respectively. The receiver operating characteristic area under the curve for the whole tumor size, CTR, whole tumor volume, and solid part volume used to identify recurrence were 0.60, 0.68, 0.58, and 0.69, respectively. A univariate analysis revealed that the whole tumor size, CTR, whole tumor volume, and solid part volume were associated with disease-free survival (DFS). A multivariate analysis of these factors identified the solid part volume to be the only independent factor for the prediction of DFS. Conclusions: The whole tumor volume and the solid part volume were associated with DFS. In particular, the solid part volume was a very useful factor for predicting prognosis in clinical stage IA NSCLC.