A comparative study of the efficacy and safety of PD-1/L1 inhibitor and platinum-containing dual-agent chemotherapy in patients with advanced non-small cell lung cancer resistant to EGFR-TKIs.

Objective: To assess the efficacy and safety of combining Programmed Death-1/Programmed Death-Ligand 1 (PD-1/L1) inhibitors with platinum-containing chemotherapy for treating late-stage Non-Small Cell Lung Cancer (NSCLC) patients who have developed resistance to Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors (EGFR-TKIs).

Methods: A retrospective analysis was conducted at Baoji Traditional Chinese Medicine Hospital involving 133 patients with advanced NSCLC who had shown resistance to EGFR-TKIs and were treated from October 2018 to May 2021. The cohort was categorized into two groups: one treated with immune checkpoint inhibitors (ICIs) plus chemotherapy and antiangiogenic agents (ICIs+BCP group), and the other treated with ICIs alone (ICIs group). Baseline data collected included demographic factors, smoking status, PD-L1 Tumor Proportion Score (TPS), EGFR mutation, Eastern Cooperative Oncology Group (ECOG) score, and routine blood markers prior to second-line therapy. Computed Tomography (CT) scans were performed every two treatment courses to evaluate the treatment efficacy.

Results: The ICIs+BCP group exhibited a statistically significant improvement in Overall Survival (OS) compared to the ICIs group (P=0.001). Cox survival analysis uncovered age (P=0.012), PD-L1 TPS expression (P<0.001), treatment regimen (P=0.006), Neutrophil-to-Lymphocyte Ratio (NLR) (P=0.024), and Platelet-to-Lymphocyte Ratio (PLR) (P=0.005) as independent factors influencing OS in patients with advanced NSCLC resistant to primary-line EGFR-TKI therapy. The nomogram model, based on these prognostic factors, exhibited Area Under the Curve (AUC) values of 0.823 and 0.769, indicating its predictive accuracy for 1-year and 2-year survival, respectively.

Conclusion: Combining ICIs with BCP prolongs OS in patients with NSCLC resistant to EGFR-TKIs. This study underscores the importance of personalized treatment plans and biomarker evaluations to improve outcomes in drug-resistant cases.