Real World Study of Efficacy and Safety of Atezolizumab Plus Chemotherapy in Chinese Patients With ES-SCLC

Inclusion Criteria: * Histologically or cytologically confirmed ES-SCLC (per the Veterans Administration Lung Study Group \[VALG\] staging system) * No prior systemic treatment for ES-SCLC * 18-80 years old, or more than 10 months of expected natural survival; * Eastern Cooperative Oncology Group performance status of 0 or 1 or 2 * Measurable disease, as defined by RECIST v1.1 Adequate hematologic and end organ function * Treatment-free for at least 6 months since last chemo/radiotherapy, among those treated (with curative intent) with prior chemo/radiotherapy for limited-stage SCLC * The subject must be willing and able to participate in the study procedures and to understand and sign the informed consent Exclusion Criteria: * Pregnancy or breastfeeding, or intention of becoming pregnant during study treatment or within 5 months after the final dose of atezolizumab or 6 months after the final dose chemotherapy. Women of childbearing potential must have a negative serum pregnancy test result within 14 days prior to initiation of study treatment. Patients or family members cannot understand the conditions and goals of this study. The subject has an estimated life expectancy of less than 10 months The subject is unable or unwilling to comply with the study requirements or follow-up schedule