Preoperative Neoadjuvant Immunotherapy Combined With Chemotherapy for Stage Ⅲ Unresectable Non-small Cell Lung Cancer

Inclusion Criteria: 1. Age :18 Years to 75 Years; 2. ECOG physical score status of 0 or 1 points; 3. Expected survival time ≥ 6 months; 4. According to the eighth edition of the AJCC/UICC TNM staging system, patients were pathological diagnosed with Stage III NSCLC and had one of the following conditions: 1) A complete resection (R0) would not be possible, based on evaluation within a multidisciplinary team, including an experienced thoracic surgeon; 2) Multiple ipsilateral mediastinal lymph nodes metastasized into large masses or multistation metastases (IIIA: T1-2N2 or IIIB: T3-4N2); 3) Contralateral hilar or mediastinal lymph nodes, or ipsilateral or contralateral scalene or supraclavicular lymph nodes metastasis (IIIB: T1-2N3; IIIC: T3-4N3); 4) The lesion invaded the heart, aorta, or esophagus (IIIA: T4N0-1). 5. EGFR mutation or ALK mutation was negative; 6. Patients with at least one evaluable or measurable lesions as per RECIST version 1.1; 7. Patients were newly diagnosed with non-small cell lung cancer, without radiotherapy, chemotherapy, surgery or molecule-targeted treatment. 8. Patients must have enough cardiopulmonary function for the expected pulmonary resections for lung cancer. 9. The main organ function meets the following criteria:1) Blood routine:a. ANC ≥ 1.5×109/L; b. PLT ≥ 100×109/L; c. HB ≥ 90 g/L; 2) Blood biochemistry:TBIL ≤ 1.5×ULN;ALT、AST≤ 2.5×ULN;sCr≤1.5×ULN; 3) Blood coagulation: INR≤1.5×ULN and APTT≤1.5×ULN，endogenous creatinine clearance rate≥45ml/min(Cockcroft-Gault formula); 10. Pregnancy test (serum or urine) has to be performed for woman of childbearing age within 7 days before enrolment and the test result must be negative. They shall take appropriate methods for contraception during the study until the 3 months post the last administration of study drug. For men, (previous surgical sterilization accepted), shall agree to take appropriate methods of contraception during the study until the 3 months post the last administration of study drug; 11. Patient has to voluntarily join the study and sign the Informed Consent Form for the study. Exclusion Criteria: 1. Patients with autoimmune disease, or a history of autoimmune disease within 2 years prior to the first use of the study drug including but not limited to the following: autoimmune hepatitis, interstitial pneumonia, uveitis, enteritis, hepatitis, pituitary inflammation, vasculitis, myocarditis, nephritis, hyperthyroidism, hypothyroidism which can be included after hormone replacement therapy; Subjects with childhood asthma have been completely alleviated and without any intervention or vitiligo in adulthood can be included; 2. Subjects with congenital or acquired immunodeficiency such as HIV infection, active hepatitis B (HBV DNA ≥ 2000 IU/mL), hepatitis C (hepatitis C antibody is positive); 3. Subjects with a condition requiring other immunosuppressive medications before 7 days of study drug administration firstly, not including inhaled corticosteroids or physiological doses of systemic treatment with either corticosteroids (\> 10 mg daily prednisone equivalents); 4. Has received a live vaccine within 4 weeks of planned start of study therapy; 5. Other malignancies have been diagnosed within 5 years prior to the first use of the study drug (excluding skin basal cell carcinoma that has been cured, skin squamous cell carcinoma, and / or carcinoma in situ that has undergone radical resection); 6. Patients with a current or history of pulmonary fibrosis, interstitial pneumonia, pneumoconiosis, radiologic pneumonia, drug-induced pneumonia and severe impairment of lung function; 7. Patients with serious or uncontrollable systemic diseases, such as: Patients with hypertension that is difficult to control (systolic blood pressure ≥140 mmHg and diastolic blood pressure ≥90 mmHg); Patients with myocardial ischemia and myocardial infarction above class II (including QT interval prolongation, for man ≥ 450 ms, for woman ≥ 470 ms); 8. Severe infection within 4 weeks before the first administration (such as intravenous drip of antibiotics, antifungal drugs or antiviral drugs), or fever of unknown origin (\> 38.5 ℃) within 4 weeks before the first administration; 9. Allogeneic organ transplantation (except corneal transplantation) or allogeneic hematopoietic stem cell transplantation; 10. Pregnant or nursing women; 11. Patients with a history of hypersensitivity to any of the study drugs, similar drugs, or excipients; 12. Participated in other clinical trials within 4 weeks; 13. Patients has received the following therapies: anti-PD-1, anti-PD-L1, or anti-PD-L2 drugs or drugs that target another stimulator or synergistically inhibit T cell receptors (e.g., CTLA-4, OX-40, CD137); 14. The investigator believes that there are any conditions that may damage the subject or result in the subject being unable to meet or perform the research request.