Abstract
BACKGROUND: Immunotherapy represented by immune checkpoint inhibitors (ICIs) has been widely used in the treatment of lung cancer. There are controversies in clinical practice for patients with advanced non-small cell lung cancer (NSCLC) and high programmed cell death-ligand 1 (PD-L1) expression receiving ICIs monotherapy or combination chemotherapy. METHODS: This study retrospectively analyzed the clinical data of 49 patients with advanced NSCLC and high PD-L1 expression. Immunohistochemistry was performed with 22C3 antibody, and the expression level of PD-L1 was evaluated according to tumor proportion score (TPS). Objective response rate (ORR) and progression free survival (PFS) were compared by groups of different clinical characteristics. RESULTS: ORR of monotherapy and combination therapy group was 47.1% (8/17) and 43.8% (14/32), respectively, without statistical difference (P=0.825). The median PFS of monotherapy and combination therapy group was 8.0 months and 6.8 months, respectively, without statistical difference (P=0.502). Statistical analysis of predictors of immunotherapy for the patients showed first-line immunotherapy had better ORR than subsequent immunotherapy (12/19, 63.2% vs 10/30, 33.3%, P=0.041), however no difference in PFS. And there were no differences in ORR or PFS among groups of age, gender, smoking status, performance status (PS), pathological type, tumor size and tumor-node-metastasis (TNM) stage. CONCLUSIONS: The therapeutic effect is similar between ICIs monotherapy and combination chemotherapy for patients with advanced NSCLC and high PD-L1 expression. ORR of first-line immunotherapy was better in patients with advanced NSCLC and high PD-L1 expression. The optimal treatment for this population remains further prospective clinical studies.