Prospective Phase II Clinical Study of Stereotactic Body Proton Therapy (SBPT) for Lung Cancer

Inclusion Criteria: 1. .Lung cancer confirmed by histology and/or cytology; and in the absence of pathological diagnosis, patients who meet the following conditions can also be included: diagnosed by more than 2 imaging modalities, and the clinical diagnosis of lung cancer is confirmed after multidisciplinary team (MDT) discussion. 2. The clinical staging based on positron emission tomography(PET)-computer tomography(CT) examination is: cT1\~3 N0M0, stage IA-IIB (AJCC eighth edition). 3. Age: 18 years and above. 4. Karnofsky(KPS) score ≥60. 5. The doctor assesses that surgical treatment is not suitable or the patient refuses surgery. 6. Relatively good organ function: 7. Normal bone marrow function: white blood cell (WBC)≥3×109/L, Platelet ≥80×109/L, Hemoglobin(HGB)≥90g/L 8. Normal liver and kidney function: 9. Total bilirubin, Aspartate Aminotransferase(AST), and ALT(Alanine Aminotransferase)≤2.0×upper limit of normal values; 10. Creatinine clearance ≥60ml/min or creatinine ≤1.5×upper limit of normal value 11. The patient has signed an informed consent form and is willing and able to comply with planned study visits, treatment plans, laboratory tests, and other study procedures. Exclusion Criteria: 1. Patients with other malignant tumors. 2. Poorly controlled heart failure, respiratory failure, heart function, and lung function below grade 3 (including grade 3). 3. Those whose laboratory test values do not meet relevant standards before enrollment. 4. Patients who cannot cooperate with regular follow-up due to psychological, social, family and geographical reasons. 5. Women of childbearing age who have a positive pregnancy test and women who are breastfeeding. 6. Patients considered inappropriate for inclusion by other investigators.