Objective To investigate the significance of spread through air spaces (STAS) in early-stage non-small cell lung cancer (NSCLC) patients undergoing either sublobar resection or lobectomy by pooling evidence available, and to assess the accuracy of frozen sections in determining types of resection among patients with suspected presence of STAS. MethodsStudies were identified by searching databases including PubMed, EMbase, Web of Science, and The Cochrane Library from inception to July 2022. Two researchers independently searched, screened, evaluated literature, and extracted data. Statistical analysis was conducted using RevMan 5.4 and STATA 15.0. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the study. ResultsA total of 26 studies involving 23 surgical related studies (12 266 patients) were included, among which, 11 compared the outcomes of lobectomy with sublobar resection in the STAS-positive patients. NOS score≥6 points. Meta-analysis indicated that presence of STAS shortened patients' survival in both lobectomy group and sublobar resection group (RFS: HR=2.27, 95%CI 1.96-2.63, P<0.01; OS: HR=2.08, 95%CI 1.74-2.49, P<0.01). Moreover, lobectomy brought additional survival benefits to STAS-positive patients compared with sublobar resection (RFS: HR=1.97, 95%CI 1.59-2.44, P<0.01; OS: HR=1.91, 95%CI 1.47-2.48, P<0.01). Four studies were included to assess the accuracy of identifying presence of STAS on intraoperative frozen sections, of which the pooled sensitivity reached 55% (95%CI 45%-64%), the pooled specificity reached 92% (95%CI 77%-97%), and the pooled area under the curve was 0.68 (95%CI 0.64-0.72) based on the data available. Conclusion This study confirms that presence of STAS is a critical risk factor for patients with early-stage NSCLC. Lobectomy should be recommended as the first choice when presence of STAS is identified on frozen sections, as lobectomy can prolong patients' survival compared with sublobar resection in STAS-positive disease. The specificity of identifying STAS on frozen sections seems to be satisfactory, which may be helpful in determining types of resection. However, more robust methods are urgently in need to make up for the limited sensitivity and accuracy of frozen sections.