Pembrolizumab and Chemotherapy Combination Prolonged Progression-Free Survival in Patients with NSCLC with High PD-L1 Expression and Low Neutrophil-to-Lymphocyte Ratio.

The use of immune checkpoint inhibitors (ICIs) has provided overall survival (OS) benefits in patients with treatment-naïve advanced non-small cell lung cancer (NSCLC) without targetable driver mutations. However, studies comparing ICIs monotherapy with combination therapy either with chemotherapy or radiotherapy in programmed death-ligand 1 high expressors remain limited. This study aimed to retrospectively compare the treatment efficacy of the therapies by studying 47 patients with treatment-naïve advanced NSCLC who received ICI monotherapy ( n = 28) or combination therapy either with chemotherapy or radiotherapy ( n = 19). Progression-free survival (PFS) and OS were estimated using the Kaplan-Meier method and compared using log-rank tests. It was observed that patients who received combination therapy had a better PFS than monotherapy, but no such significant benefit was observed in OS. The difference in PFS was higher in the subgroup of patients with low neutrophil-to-lymphocyte ratio (NLR) than in the high-NLR patient subgroup. This study suggests that pembrolizumab in combination with chemotherapy or radiotherapy could provide a significant benefit in PFS, especially in patients with treatment-naïve advanced NSCLC with low NLR. Furthermore, our study also demonstrates the potential use of NLR as a biomarker for prediction of treatment outcomes in patients with advanced NSCLC receiving combination therapy.