Spread through air spaces affects survival and recurrence of patients with clinical stage IA non-small cell lung cancer after wedge resection

BACKGROUND: Spread through air spaces (STAS) is reportedly a significant risk factor for recurrence and a prognostic factor in patients with non-small cell lung cancer (NSCLC), especially after sublobar resection. Because wedge resection (WR) is associated with insufficient margins, we hypothesized that STAS has a greater prognostic impact in patients who undergo WR compared with segmentectomy. We aimed to clarify the value of STAS as a prognostic factor in patients with NSCLC after WR. METHODS: We evaluated 217 patients with clinical stage IA NSCLC who underwent sublobar resection. The prognostic impact of STAS in these patients was compared between the WR (n=100) and segmentectomy (n=117) cases. RESULTS: STAS was present in 15.7% of the 217 patients. STAS was a significant prognostic factor for overall survival in univariate (P<0.001) and multivariate (P=0.003) analyses for the WR cases, but not the segmentectomy cases (P=0.399). STAS was also a significant prognostic factor for freedom from recurrence in univariate (P=0.010) and multivariate (P=0.024) analyses for the WR cases, but was only marginally significant for the segmentectomy cases (P=0.050, univariate analysis). The solid tumor size on chest computed tomography was significantly related to STAS. A cut-off solid tumor size of 1.7 cm for predicting the presence of STAS was determined by receiver operating characteristic analysis. CONCLUSIONS: STAS was a significant prognostic factor for patients with clinical stage IA NSCLC who underwent WR, but not those who underwent segmentectomy.