Low-dose Radiotherapy Combined With Concurrent Chemotherapy, Toripalimab and Tifcemalimab in the Treatment of ES-SCLC

Inclusion Criteria: * Age ≥ 18 years, male or female; * Histologically or cytologically confirmed extensive stage small cell lung cancer; * Previously untreated extensive stage small cell lung cancer; * ECOG PS 0-1; * Measurable lesions according to RECIST 1.1, and measurable lesions can only be included in previously irradiated lesions if the lesion shows definite disease progression after radiotherapy; * Expected survival ≥ 3 months; * Normal function of major organs, that is, meet the following criteria: neutrophils ≥ 1.5 × 109/L, platelet count ≥ 100 × 109/L, hemoglobin ≥ 90 g/L; serum creatinine ≤ 1.5 × ULN and creatinine clearance ≥ 50 mL/min; serum total bilirubin ≤ 1.5 × ULN, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × ULN; ALT and AST ≤ 5 × ULN in patients with liver metastases; international normalized ratio (INR) or prothrombin time (PT) ≤ 1.5 × ULN unless the subject is receiving anticoagulant therapy, activated partial thrombin time (aPTT) ≤ 1.5 × ULN unless the subject is receiving anticoagulant therapy; * Female subjects of childbearing potential, as well as male subjects with partners of childbearing potential, need to use a medically recognized contraceptive (such as an intrauterine device, contraceptive, or condom containing spermicide) during study treatment and for at least 4 months after the last use of study drug; * Voluntary participation in this study, signed informed consent, good compliance, with follow-up. Exclusion…