Spread through air spaces is a predictive factor of recurrence and a prognostic factor in stage I lung adenocarcinoma.

Abstract

Spread through air spaces (STAS) is considered a prognosticator related to local recurrence. We assessed the prognostic impact of spread through air spaces and local recurrence in stage I lung adenocarcinoma. From July 2004 to November 2014, 877 lung cancer patients underwent surgery, of whom 318 with pathological stage I adenocarcinoma were reviewed. We investigated the characteristics of spread through air spaces and analysed the relationship between spread through air spaces and prognosis. The median follow-up was 30 months. Of the 318 patients, 47 (14.8%) had spread through air spaces. The patients with spread through air spaces were associated with male sex (P < 0.001), smoking (P < 0.001), solid nodules (P < 0.001), stage IB disease (P = 0.006), epidermal growth factor receptor mutation negativity (P < 0.001), and lymphovascular (P < 0.001) and pleural invasion (P = 0.001). Among the preoperative findings, spread through air spaces was significantly related to solid nodules on computed tomography. Local recurrence occurred in 11 of 47 (23.4%) cases with spread through air spaces and 10 of 271 (3.7%) cases without spread through air spaces (P < 0.01). Univariate analysis showed that the overall 5-year survival rates were 62.7 and 91.1% in cases with and without spread through air spaces, respectively (P < 0.01), and the recurrence-free 5-year survival rates were 54.4 and 87.8% in cases with and without spread through air spaces, respectively (P < 0.01). Multivariate analysis confirmed spread through air spaces as a significant prognosticator for overall survival and a predictive factor for recurrence after surgery. Among stage I lung adenocarcinoma patients, spread through air spaces was found frequently in the invasive cases and was closely related to poor prognosis and recurrence.