Therefore, to the best of our knowledge, this is the first study to comprehensively analyze the efficacy and safety of both PD‐1 inhibitors and PD‐L1 inhibitors combined with chemotherapy as the FL treatment in ES‐SCLC in the real world; we found that the prognosis of patients treated with PD‐1 inhibitors is not worse than patients treated with PD‐L1 inhibitors. Here, CD274 is linked to small cell lung carcinoma.