Prognostic factors and survival outcomes in older adults with extensive-stage small cell lung cancer: A multicenter retrospective cohort study

Extensive-stage small cell lung cancer (ES-SCLC) in older adults is associated with poor outcomes, and optimal management in this population remains challenging. This study aimed to identify clinical and treatment-related factors associated with survival in patients aged ≥70 years with ES-SCLC. A retrospective multicenter cohort study included 135 older adults (aged ≥70 years) diagnosed with ES-SCLC across 3 tertiary centers. All patients received at least 1 cycle of platinum-etoposide-based chemotherapy. Demographic, clinical, and treatment variables - including metastatic sites, number of chemotherapy cycles, thoracic radiotherapy (TRT), prophylactic cranial irradiation, and palliative radiotherapy to extracranial metastases - were collected. Survival outcomes were estimated using the Kaplan-Meier method and compared using the log-rank test. Prognostic factors for progression-free survival and overall survival (OS) were evaluated using Cox proportional hazards regression models. The median age was 73.2 years; 88.1% of patients were male. The objective response rate was 69.9%. Median progression-free survival and OS were 7.1 and 8.3 months, respectively (95% CI: 6.09-8.17 and 7.67-8.93). In multivariate analysis, Eastern Cooperative Oncology Group performance status ≥2 (P