Factors Affecting the Efficacy and Safety of First-Line Anti-PD-1 Therapy in Advanced Non-Small Cell Lung Cancer

Objective: This study assesses peripheral blood parameters as predictors of programmed cell death protein-1 (PD-1) inhibitor efficacy in advanced non-small cell lung cancer (NSCLC). Methods: We retrospectively analyzed 169 advanced NSCLC patients receiving first-line PD-1 inhibitor-based therapy. Baseline blood parameters and clinical characteristics were recorded. Logistic regression assessed associations with immune-related adverse events (irAEs). Chi-square tests compared efficacy and safety across treatment groups. Results: Baseline albumin/fibrinogen ratio (ALB/FIB) and PIV were associated with all-grade irAEs (p < 0.05), while PIV was markedly associated with grade ≥3 irAEs (p < 0.01). Multivariate analysis identified that the baseline pan-immune inflammation value (PIV) was independently associated with the occurrence of irAEs (p < 0.01). Compared to PD-1 inhibitor plus chemotherapy, adding bevacizumab increased oral mucositis (p = 0.010) and was linked to a later clinical stage (p = 0.001). In patients receiving peri-immunotherapy radiotherapy, leukopenia was more frequent (p = 0.030). Conclusion: Baseline PIV is independently associated with the occurrence of irAEs in advanced NSCLC patients receiving first-line PD-1 inhibitor therapy. Adding bevacizumab or radiotherapy may modify safety profiles.