The real-world observational study was designed to explore the odd factors of lymph metastases in the patients with T1 non-small cell lung cancer, the effects of clinical characteristics on lymph metastases, and compare the differences in lymph metastases in the subgroups.

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.

Inclusion Criteria:

• Patients who received surgeries from 2015 to 2017;
• Pathologically diagnosed patients with T1 non-small cell lung cancer;

Exclusion Criteria:

- Patients with tumor treatments (including chemotherapies, radiotherapies, biological therapies, intervention therapies)

The eligible subjects are the Chinese T1 patients with non-small cell lung cancer complicated with lymph metastases