PD-L1 Antibody (TQB2450) Plus Chemotherapy for Previously Untreated Limited- Stage Small-cell Lung Cancer

This study is testing whether adding an immunotherapy drug called TQB2450 (a PD-L1 inhibitor) to standard chemotherapy improves outcomes for patients with limited-stage small-cell lung cancer — a fast-growing type of lung cancer that hasn't yet spread widely. **You may be eligible if...** - You are 18 or older - You have been diagnosed with small-cell lung cancer (SCLC), confirmed by biopsy - Your cancer is limited-stage or extensive-stage (locally advanced) - You are in good general health (ECOG score 0–1) - Your blood counts, liver, and kidney function are within acceptable ranges - You have at least one measurable lesion on imaging **You may NOT be eligible if...** - You have received prior chemotherapy or immunotherapy for this cancer - You have active autoimmune disease - You have uncontrolled infections (including active hepatitis or HIV) - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.