Spread through air spaces predicts a worse survival in patients with stage I adenocarcinomas >2 cm after radical lobectomy

Background: The aim of this study was to evaluate the significance of spread through air spaces (STAS) in early lung adenocarcinomas after radical lobectomy and lymphadenectomy. Methods: A total of 242 patients with lung adenocarcinomas less than 4 cm (8th pStage I) were selected from the lung cancer patients surgically treated from January, 2009 to September, 2011. Pathological review focused on STAS as well as histological subtypes, blood vessel & neural invasion, pathological tumor size etc. Recurrence or disease-free survival (DFS) and overall survival (OS) were compared between patients as stratified by STAS and tumor size. Results: STAS was observed in 33.47% (81/242) patients, which was significantly correlated with histological predominant subtype (χ 2 =25.903, P=0.093×10 −3 ) and differentiation grade (χ 2 =23.986, P=0.025×10 −3 ). Patients with STAS (+) showed a comparable PFS (P=0.268) and OS rates (P=0.100) in all stage I cases, but a significant lower PFS (P=0.029) and OS (P=0.013) in tumors within 2 Conclusions: Presence of STAS was a significant worse predictor for pStage I patients with lung adenocarcinoma >2 cm who underwent radical lobectomy, while it is not significant in patients with tumor ≤2 cm. These findings may be helpful in assessing postoperative therapy stratified by tumor size and STAS status.