This is a real-world study with the largest sample size investigating the pathological tumor and lymph node responses to neoadjuvant immunochemotherapy in non-small cell lung cancer to date. Patients with initially unresectable NSCLC underwent immunochemotherapy and response to treatment was assessed after every two treatment cycles. Clinicopathologic features of patients including epidemiological data, clinical manifestations, operation strategies, pathological findings, and prognostic information were recorded and evaluated.

Inclusion Criteria:

• Patients with stage III NSCLC who received neoadjuvant immunochemotherapy.
• early-stage NSCLC patients who were initially unresectable.
• 18 years of age or older.
• Karnofsky performance status (KPS) score of 100 or 90.

Exclusion Criteria:

• Patients with stage IV NSCLC
• Patients with known ALK translocations or EGFR mutations.
• Karnofsky performance status (KPS) score <90.

Patients with stage II-III NSCLC who received neoadjuvant immunochemotherapy (time) in Guangdong Provincial People's Hospital were eligible for this study. We also included early-stage NSCLC patients who were unsuitable or unable to tolerate surgery after first evaluation. Eligible patients were 18 years of age or older, had a karnofsky performance status (KPS) score of 100 or 90 (on a scale from 0 to 100 with higher score indicating better ability to carry out daily activities). Patients with distant tumor metastasis or with known ALK translocations or EGFR mutations were excluded.