Retrospective study of survival outcomes and molecular predictors in small cell lung cancer with brain metastases receiving immunotherapy

A retrospective study at Southern Medical University (Guangzhou, China) evaluated the real-world efficacy of chemoimmunotherapy with or without brain radiotherapy in patients with small cell lung cancer (SCLC) and brain metastases (BM). A total of 133 consecutive patients with de novo SCLC-BM were analyzed. Patients were categorized into a chemotherapy-only cohort (n=54) and a chemoimmunotherapy cohort (n=79). Chemoimmunotherapy was significantly associated with prolonged median progression-free survival (6.1 versus 5.1 months; p=0.034) and overall survival (10.2 versus 9.0 months; p=0.019) compared to chemotherapy alone. Time-dependent multivariate analysis confirmed that both chemoimmunotherapy (aHR 0.65; p=0.032) and brain radiotherapy (time-dependent HT 0.63; p=0.040) were independent protective factors for overall survival. The longest median overall survival (15.2 months) was observed in patients receiving the combination of chemoimmunotherapy and brain radiotherapy. In exploratory biomarker analyses, high baseline NSE coupled with low CEA levels correlated with poor prognosis. SCLC-N and SCLC-P subtypes were associated with significantly inferior survival compared to SCLC-A ad SCLC-TN subtypes. The authors conclude that first-line chemoimmunotherapy is associated with favorable survival outcomes in patients with SCLC-BM, with longest survival observed for combination with brain radiotherapy.