Radiologic features associated with spread through airspaces in Stage IA nonsmall-cell lung cancer undergoing segmentectomy

ABSTRACT BACKGROUND: Spread through airspaces (STAS) has emerged as a significant prognostic factor in early-stage nonsmall-cell lung cancer (NSCLC). In patients with STAS-positive tumors, lobectomy is often preferred over sublobar resection due to the higher recurrence risk. Therefore, preoperative identification of STAS is crucial for optimal surgical planning and avoiding reoperations. This study aimed to identify radiological features independently associated with STAS positivity in the preoperative setting. METHODS: This single-center, retrospective cross-sectional study included 99 patients with stage T1a-bN0M0 NSCLC who underwent segmentectomy between 2015 and 2023. Preoperative thoracic computed tomography (CT) and positron emission tomography/CT findings were analyzed. Univariate and multivariate logistic regression analyses were performed to identify radiologic features associated with STAS positivity. RESULTS: Ninety-nine patients were included, and STAS positivity was identified in 38 (38.3%) patients. The mean nodule diameter was significantly larger in STAS-positive tumors than in STAS-negative tumors (18.1 ± 6.0 mm vs. 15.0 ± 4.4 mm; P = 0.004). In multivariable logistic regression analysis, nodule diameter remained independently associated with STAS positivity (odds ratio: 1.11 per 1-mm increase; 95% confidence interval: 1.01–1.22; P = 0.028). An optimal cutoff value of 15 mm was identified for the association between tumor size and STAS positivity. CONCLUSION: Among patients with Stage IA NSCLC undergoing segmentectomy, larger tumor diameter on preoperative CT was independently associated with STAS positivity. Tumor size may provide supportive information during preoperative assessment and surgical planning. Further studies are needed to improve the preoperative identification of STAS and refine risk stratification in early-stage NSCLC.