Anatomical Location and Metastasis Pattern of Intrapulmonary Lymph Nodes in NSCLC (ECTOP-1010)

Inclusion Criteria: 1. Preoperative examination showed patients with clinical T1 peripheral non-small cell lung cancer (NSCLC); 2. The lesion is located in a single lung segment or between two adjacent lung segments; 3. Perform radical lobectomy; 4. The preoperative examination did not reveal unresectable lymph nodes; 5. Have not received any other tumor-related treatments (including chemotherapy, radiotherapy, targeted therapy, immunotherapy, etc.) before surgery; 6. No malignant tumor history; 7. No contraindications to surgery (ECOG score 0-1 points); Exclusion Criteria: 1. Pathology revealed patients with non-T1 stage non-small cell lung cancer (NSCLC); 2. Radical lobectomy is not performed; 3. Acception of any anti-tumor treatment before surgery (excluding Chinese medicine treatment); 4. Refused to enter the group or asked to leave the group.