Efficacy and safety of immune checkpoint inhibitors plus anlotinib in small cell lung cancer with brain metastases: a retrospective, multicentre study

Previous studies showed that both immune checkpoint inhibitors (ICIs) and anlotinib have central nervous system (CNS) efficacy. This study aimed to evaluate the efficacy and safety of ICIs combined with anlotinib in small cell lung cancer (SCLC) patients with brain metastases (BMs).We retrospectively reviewed SCLC patients with CNS metastases confirmed by brain magnetic resonance imaging (MRI). Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) and Response assessment in neuro-oncology brain metastases (RANO-BM) were used to evaluate treatment response to ICIs plus anlotinib. Kaplan-Meier analysis and Cox regression analysis were performed to determine patient's prognosis.Sixty-six patients with baseline BMs were included. For patients with measurable intracranial lesions, the intracranial objective response rate (ORR) was 29.2% based on RECIST 1.1 criteria and was 27.1% based on RANO-BM criteria. The median intracranial progression-free survival (PFS) was 9.0 months (95% confidence interval [CI], 6.5-11.5 months). The median overall survival (OS) was 13.4 months (95% CI, 10.7-20.5 months). Multivariate Cox regression analysis showed that high disease burden (hazard ratio [HR] = 4.83, P < 0.001), multiple BMs (HR = 2.71, P = 0.036), and more than or equal to 3 prior lines of therapy (HR = 2.56, P = 0.023) were independent negative predictors of OS. The overall incidence of treatment-related adverse events (TRAEs) was 75.8%, and grade 3-4 TRAEs were reported in 19.7% of patients.Our results suggested that ICIs plus anlotinib had potent CNS efficacy with tolerable toxicity and could be a promising treatment option for SCLC patients with BMs.