This study is a multicenter, prospective investigation aiming to evaluate the efficacy and safety of low-dose radiotherapy (15Gy/1.5 Gy bid × 10 fractions) combined with 4-6 cycles of systemic chemotherapy concurrently with Adebrelimab, followed by Adebrelimab maintenance therapy for up to two years, in subjects with extensive-stage small cell lung cancer (ES-SCLC). Additionally, immunohistochemical detection of the expression levels of four key transcriptional proteins-YAP1, NEUROD1, ASCL1, and POU2F3-will be performed to guide the molecular subtyping of SCLC. Based on these findings, we will explore the differential therapeutic outcomes of this regimen across distinct molecular subtypes (A/N/P/Y/I/AN/QN), with the goal of identifying the subject population most likely to benefit from this treatment modality, thereby optimizing clinical decision-making.
Age ≥18 years and ≤75 years;
Histologically or cytologically confirmed SCLC;
No malignant pleural effusion or pericardial effusion;
No prior history of thoracic radiotherapy or thoracic surgery;
Presence of interstitial pneumonia or infectious fever prior to treatment;
Comorbid autoimmune diseases or long-term oral corticosteroid use (including those who received oral corticosteroids within 14 days prior to treatment);
Prior history of thoracic radiotherapy or thoracic surgery;
Presence of Grade ≥3 hematologic toxicity or hepatic/renal impairment;