Clinical Outcomes of First-Line Pembrolizumab Monotherapy in Advanced NSCLC With PD-L1 Tumor Proportion Score of 1% to 49%: A Retrospective Multicenter Study

First-line pembrolizumab monotherapy demonstrated moderate efficacy and acceptable safety in patients with advanced NSCLC with PD-L1 TPS of 1% to 49%. Liver metastasis, high NLR, and poor performance status were identified as prognostic factors.