Spread Through Air Spaces Is a Prognostic Factor in Sublobar Resection of Non-Small Cell Lung Cancer

BackgroundSpread through air spaces (STAS) identified in lung cancer is considered to be a risk factor for recurrence after surgery. The purpose of this study is to clarify the prognostic impact of STAS in sublobar resections.MethodsWe studied 514 patients with clinical stage IA cancers: 329 underwent lobectomies and 185 underwent sublobar resections. We assessed the prognostic impact of STAS in the cases with a sublobar resection for stage IA lung cancer versus the cases with a lobectomy.ResultsSTAS was found in 73 of 329 (22.2%) lobectomy cases and 31 of 185 (16.8%) sublobar resection cases. For overall survival, univariate analysis revealed that STAS was not a prognostic factor in the lobectomy group, but it was a significantly worse prognostic factor for the sublobar resection group in both univariate and multivariate analyses. For the recurrence-free rate, multivariate analysis showed STAS was not a risk factor in the lobectomy group, but it was a significant risk factor for the sublobar resection group in both univariate and multivariate analyses. Patients with STAS and sublobar resection had a significantly higher rate of pulmonary metastases than did patients with STAS and lobectomy (8 of 31 [25.8%] vs 6 of 73 [8.2%]).ConclusionsSTAS is a prognostic factor of poor outcomes for sublobar resection in patients with lung cancer. The worse prognosis for sublobar resection would be associated with STAS. Spread through air spaces (STAS) identified in lung cancer is considered to be a risk factor for recurrence after surgery. The purpose of this study is to clarify the prognostic impact of STAS in sublobar resections. We studied 514 patients with clinical stage IA cancers: 329 underwent lobectomies and 185 underwent sublobar resections. We assessed the prognostic impact of STAS in the cases with a sublobar resection for stage IA lung cancer versus the cases with a lobectomy. STAS was found in 73 of 329 (22.2%) lobectomy cases and 31 of 185 (16.8%) sublobar resection cases. For overall survival, univariate analysis revealed that STAS was not a prognostic factor in the lobectomy group, but it was a significantly worse prognostic factor for the sublobar resection group in both univariate and multivariate analyses. For the recurrence-free rate, multivariate analysis showed STAS was not a risk factor in the lobectomy group, but it was a significant risk factor for the sublobar resection group in both univariate and multivariate analyses. Patients with STAS and sublobar resection had a significantly higher rate of pulmonary metastases than did patients with STAS and lobectomy (8 of 31 [25.8%] vs 6 of 73 [8.2%]). STAS is a prognostic factor of poor outcomes for sublobar resection in patients with lung cancer. The worse prognosis for sublobar resection would be associated with STAS.