Neoadjuvant/Adjuvant Pembrolizumab Plus Chemotherapy

Inclusion Criteria: 1. Primary non-small cell lung cancer (NSCLC) confirmed by cytology or histology 2. Stage IIa to selected IIIb ( t1-4, n0-2 ) NSCLC according to the TNM stage (8th Edition) of IASLC, which is considered to be resectable; 3. At least one evaluable focus judged according to RECIST 1.1 standard (on spiral CT, the longest diameter of tumor should be at least 10 mm, the shortest diameter of metastasis lymphnode should be at least 20 mm) 4. ECOG PS 0 or 1 5. Adequate tumor samples available for gene detection (EGFR/ALK /ros1) with non-squamous and specimens for PD-L1 immunohistochemistry (IHC) in all the subjects. 6. Male or female, ≥ 18 years old 7. Adequate blood function: absolute neutrophil count (ANC) ≥ 2 × 109 / L, platelet count ≥ 100 × 109 / L and hemoglobin 110 ≥ 9 g / dl 8. Adequate liver function: total bilirubin ≤ upper limit of normal value (ULN); AST and alt ≤ upper limit of normal value (ULN); alkaline phosphatase ≤ upper limit of normal value (ULN) 9. Adequate renal function: serum creatinine ≤ upper limit of normal value (ULN) or calculated creatinine clearance ≥ 60ml / min 10. No history of using anti-tumor drug treatment before 11. For patients who have had previous surgery, it is required that more than 4 weeks have passed since the start of study treatment, and the patients have recovered 12. Sign the informed consent form (the informed consent form needs to be approved by the independent ethics committee, and the informed consent of the patient should be obtained before starting any substantive trial procedure) Exclusion Criteria: 1. Carrying activating mutations in the TK domain of EGFR or any variety of alterations in the ALK gene or other known targetable driver mutations. 2. Active, known or suspected autoimmune disease. 3. Other active malignancy in the last 5 years (except non-melanoma skin cancers, and the following in situ cancers: bladder, gastric, colon, endometrial, cervical/dysplasia, melanoma, or breast). 4. Prior treatment with anti-PD-1, anti-CTLA-4 (cytotoxic T lymphocyte-associated antigen (CTLA-4), or anti-PD-L1 therapeutic antibody or pathway-targeting agents 5. History of allergy to study drug components excipients 6. Having any uncontrolled systemic diseases, including active infection, uncontrolled hypertension, diabetes, unstable angina, congestive heart failure, acte myocardial infarction (within 3 months before treatment), serious arrhythmia requiring drug treatment, liver, kidney and metabolic diseases 7. Women in pregnancy or lactation