If a patient with small cell lung cancer is in good physical condition, the first-line chemotherapy regimen often recommended is etoposide combined with cisplatin, or etoposide combined with carboplatin, and irinotecan combined with cisplatin or irinotecan combined with carboplatin. If the patient’s physical status is poor, a comprehensive analysis can be made based on the patient’s tumor condition, body status, and the wishes of the patient and family, and single agent chemotherapy or reduced dose combination chemotherapy, combined with local radiotherapy if necessary, can be chosen. If the tumor is in complete remission after first-line chemotherapy, prophylactic brain irradiation can also be performed. If disease progression occurs after or during treatment, second-line chemotherapy or participation in clinical trials is required.