Real-world evaluation of first-line treatment of extensive-stage small-cell lung cancer with atezolizumab plus platinum/etoposide: a focus on patients with brain metastasis

Purpose A previous real-world study conducted in China confirmed that first-line atezolizumab, in combination with etoposide/platinum (EP), leads to significantly longer progression-free survival (PFS) compared to EP alone in patients with extensive-stage small-cell lung cancer (ES-SCLC). The present study aimed to provide updated survival outcome data and evaluate the clinical efficacy of atezolizumab plus chemotherapy in ES-SCLC patients with brain metastasis (BM). Methods This retrospective study included 225 patients with ES-SCLC who were treated with EP alone (EP group) or a combination of EP + atezolizumab (atezolizumab group). Survival outcomes for the total study sample and patients in the BM subgroup were estimated using the Kaplan–Meier method. Results The atezolizumab group continued to demonstrate significantly longer PFS than the EP group (hazard ratio [HR], 0.68). The median overall survival (OS) was 26.2 months in the atezolizumab group vs. 14.8 months in the EP group (HR, 0.63). Additionally, among the BM patients in our study, the median PFS was found to be longer in the atezolizumab group (7.0 months) than in the EP group (4.1 months) (HR, 0.46). The OS of the BM patients did not differ significantly between the two treatment groups. Conclusions The addition of atezolizumab to EP as a first-line treatment for ES-SCLC was found to improve survival outcomes. This treatment combination may also prolong PFS in patients with BM, regardless of the administration of cranial irradiation. However, among the BM patients in our study, there was no significant difference in OS between the two treatment groups.