The trial is a multi-centre, real-world non-interventional observational study. In the study, the patients with T1 non-small cell lung cancer enrolled in clinics from 2015 to 2017 were included via a retrospectively review method and the study data on patient demographic/tumor biological characteristics, and clinical treatments were collected to explore the clinical odd factors of lymph metastases, evaluate the effects of clinical characteristics on lymph metastases, and compare the differences in lymph metastases in the subgroups.
