First-line Treatment for ES-SCLC with Chemotherapy Combined with PD-1/PD-L1 Inhibitor Sequential Thoracic Radiotherapy

This study is testing whether adding targeted chest radiation therapy after chemotherapy plus immunotherapy can further improve outcomes in patients with extensive-stage small cell lung cancer (SCLC) — an aggressive form of lung cancer — who have not progressed on their initial treatment. **You may be eligible if...** - You are between 18 and 75 years old - You have confirmed extensive-stage small cell lung cancer (SCLC) - You have completed 4–6 cycles of chemotherapy combined with a PD-1 or PD-L1 immunotherapy drug and have not progressed - You have at least one measurable lung tumor on imaging - Your overall health is rated 0–1 on standard performance scales **You may NOT be eligible if...** - You have progressed on your initial chemotherapy + immunotherapy treatment - You have previously had chest radiation - You have active brain metastases - You have serious heart or lung conditions that would make radiation unsafe - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.