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 patients with spread through air spaces and lobectomy (8/31 [25.8%] vs. 6/73 [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.