Inclusion Criteria:
* 1\. Voluntary Participation，willing to participate in this study and has signed the Informed Consent Form (ICF).
2\. Age, ≥18 years old, both male and female. 3. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1.
4\. Histologically or cytologically confirmed, treatment-naïve Stage II-IIIB (N2 only) non-small cell lung cancer (NSCLC) according to the 8th edition of the American Joint Committee on Cancer (AJCC). Only patients judged as T4 based on tumor size are allowed to be enrolled; other T4 conditions (e.g., invasion of the diaphragm, mediastinal involvement) are not permitted.
5\. The primary NSCLC is deemed resectable by multidisciplinary team (MDT) assessment, which must include a thoracic surgeon specializing in oncologic surgery.
6\. Ability to provide surgical or biopsy tumor tissue for biomarker analysis (e.g., genetic sequencing, PD-L1 testing). The following must be provided before enrollment: Formalin-fixed paraffin-embedded (FFPE) tissue block from within the past 3 months, or 5-10 unstained tissue slides, or 2 core biopsy specimens, along with the relevant pathology report. Fine-needle aspiration specimens are not acceptable.
7\. At least one measurable lesion according to RECIST v1.1 criteria, as determined by the investigator.
Exclusion Criteria:
* 1\. Presence of confirmed EGFR or ALK positive mutations. 2. History of other malignancies within the past 5 years or concurrent malignancies, except for adequately treated cervical carcinoma in situ, basal cell or squamous cell carcinoma of the skin, localized prostate cancer after radical surgery, and ductal carcinoma in situ after radical surgery.
3\. Previous treatment with immune checkpoint inhibitors (e.g., PD-1/PD-L1 agents), other drugs targeting T-cell receptors (e.g., CTLA-4), immune checkpoint agonist antibodies (e.g., anti-ICOS, CD40, CD137, GITR, OX40 antibodies), or anti-tumor immune cell therapy.
4\. History of Allogeneic Hematopoietic Stem Cell Transplantation or Solid Organ Transplantation: (except for corneal transplantation).
5\. Presence of congenital or acquired immunodeficiency (e.g., HIV infection). 6. History of severe allergic reactions to other monoclonal antibodies. 7. As determined by the investigator, any other factors that may affect study outcomes or lead to premature termination of the study, such as alcohol or drug abuse, other serious diseases (including psychiatric conditions) requiring concomitant treatment, significant laboratory abnormalities, or social or family factors that may impact patient safety.
