• Age 18-75 years old; Histologically or cytologically confirmed as limited-stage small cell lung cancer (T1-3N0-1M0); All lesions of the patient (including primary lesions, lymph nodes/metastatic lesions assessed as metastases) must be jointly evaluated by surgeons, radiotherapists, and radiologists to be surgically resectable; Subjects must have measurable target lesions (according to RECIST 1.1 standards); ECOG performance status score 0-1; No history of other malignant tumors; No previous anti-tumor treatment such as surgery, radiotherapy, chemotherapy, immunotherapy, etc. related to small cell lung cancer; Patients must have sufficient cardiopulmonary function: FEV1 and DLCO of patients are ≥50% of the predicted value, echocardiography indicates LVEF ≥55%, and no clear signs of heart failure, severe coronary artery stenosis, etc. are found in various tests. Cardiopulmonary function is assessed by surgeons to be able to tolerate surgical treatment;

‣ The functional level of each important organ must meet the following requirements:

⁃ Bone marrow: absolute neutrophil count (ANC) ≥1.5× 109/L, platelets ≥100 × 109/L, hemoglobin ≥9 g/dl;

⁃ Good coagulation function: defined as international normalized ratio (INR) or prothrombin time (PT) ≤1.5 times ULN;

⁃ Liver: total bilirubin ≤1.5 times the upper limit of normal, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5 times the upper limit of normal;

⁃ Kidney: serum creatinine ≤1.25 times the upper limit of normal or creatinine clearance (calculated by Cockcroft-Gault formula) ≥60 ml/min; Men of childbearing potential and women of childbearing age must agree to take effective contraceptive measures from the signing of the main informed consent until 180 days after the last dose of the study drug. Women of childbearing age include premenopausal women and women within 2 years after menopause. Women of childbearing age must have a negative pregnancy test result within ≤ 7 days before the first administration of the study drug; Voluntarily participate in the clinical study; fully understand and be informed of this study and sign the ICF (Informed Consent Form).