To Conduct Multi-omics Integrated Studies in Peripheral Blood, Such as Fragment Omics, Metabolomics and Epigenetics, and Establish Non-invasive Dynamic Follow-up Monitoring Programs During Perioperative and Postoperative Periods (Observational Study)

Inclusion Criteria:

1. Signed written informed consent.
2. Male or female, aged ≥ 18 and \< 85 years.
3. Radical resection performed, pathologic stage IB-IIIA (8th TNM) non-small-cell lung cancer.
4. Tumor tissue and blood samples obtainable at all protocol-specified time-points.
5. No pure ground-glass nodule on imaging.
6. Completed standard neoadjuvant immunotherapy combined with platinum-based chemotherapy.

Exclusion Criteria:

1. Postoperative pathology shows other than NSCLC, including but not limited to benign lesions, small-cell carcinoma, metastasis, or indeterminate/inadequate histology.
2. Insufficient or poor-quality blood or tissue samples.
3. Pure ground-glass nodule on imaging.
4. History of any malignancy within the past 5 years.
5. Contraindication to surgery preventing radical resection.
6. Non-radical (R2) resection.
7. Pathologic stage IIIB-N3, IIIC, or IV on paraffin sections.
8. Refusal or withdrawal of informed consent.
9. Any condition deemed unsuitable by the investigator (e.g., perioperative blood transfusion, severe psychiatric disorder precluding follow-up).