Efficacy of immune checkpoint inhibitors in non-small cell lung cancer patients with different metastatic sites: A systematic review and meta-analysis.

Abstract

e21684 Background: Previous studies have demonstrated that bone, brain and liver metastases are poor prognosis factors of immune checkpoint inhibitors (ICIs) therapy in patients with non-small-cell lung cancer (NSCLC). This study aims to compare the efficacy of ICIs with conventional therapy in NSCLC patients with bone, brain or liver metastases. Methods: MEDLINE, Embase and CENTRAL were searched for prospective studies comparing ICIs with conventional therapy in NSCLC patients with bone, brain or liver metastases. Quality assessment was performed using the Newcastle-Ottawa Scale. The pooled hazard ratio (HR) of overall survival (OS) and progression-free survival (PFS) among included studies was analyzed using the random-effects model. Results: From 1,195 relevant articles, eight studies with high methodological quality consisting of 988 patients were included in the analysis. ICIs significantly improved OS for patients with brain metastases (HR = 0.57; 95%CI: 0.37-0.86; P = 0.007). Among patients with liver metastases, OS (HR = 0.72; 95%CI: 0.57-0.91; P = 0.006) and PFS (HR = 0.72; 95%CI: 0.49-0.87; P = 0.004) improvement was observed in the ICI treatment arm. No available study with bone metastases information was identified. Subgroup analysis revealed that PD-1 inhibitors could benefit patients on OS and PFS regardless of metastatic sites. Sensitivity analysis indicated good stability of this analysis. No obvious heterogeneity or publication bias was detected. Conclusions: ICIs could significantly improve OS in patients with brain metastases and both OS and PFS in patients with liver metastases. Although brain and liver metastases are generally regarded as poor prognostic factors for immunotherapy, this study still indicates ICIs are effective therapeutic options for NSCLC patients with these metastatic sites.