Efficacy and Safety of Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer With Lymph Node Metastasis

Aims/Background: Non-small cell lung cancer (NSCLC) accounts for approximately 80–85% of all lung cancers, and lymph node metastasis is a key determinant of patient prognosis, often leading to poorer clinical outcomes. Although immune checkpoint inhibitors (ICIs) have transformed the therapeutic landscape of advanced NSCLC, their specific efficacy in patients with lymph node metastases remains unclear. This study aimed to evaluate the efficacy and safety of ICI monotherapy versus chemotherapy in previously treated, unresectable NSCLC patients with lymph node metastasis. Methods: A retrospective analysis was performed on patients with unresectable, previously treated NSCLC with lymph node metastasis who received treatment at Xi’an International Medical Center Hospital between April 2019 and October 2022. Following 1:1 propensity score matching (PSM), 112 patients were included in the final analysis, comprising 56 in the ICI group (treated with pembrolizumab) and 56 in the chemotherapy group (treated with docetaxel). The primary endpoint was objective response rate (ORR), while secondary endpoints included disease control rate (DCR), overall survival (OS), and safety. Results: The ICI group demonstrated a significantly higher ORR compared with the chemotherapy group (50.0% vs. 26.8%, p = 0.012). No significant difference in DCR was observed between the groups (p = 0.057). Kaplan-Meier analysis revealed significantly longer OS in the ICI group (p = 0.009). Multivariate analysis indicated a high risk of death in the chemotherapy group compared to the ICI group (hazard ratio [HR] = 1.796; 95% confidence interval [CI]: 1.112–2.900; p = 0.017). In terms of safety, leukopenia occurred more frequently in the chemotherapy group (p = 0.039), while immune-related adverse events (irAEs), including hypothyroidism (p = 0.027) and rash (p = 0.008), were more common in the ICI group. Conclusion: In previously treated patients with unresectable NSCLC and lymph node metastasis, real-world evidence from this study suggests that pembrolizumab monotherapy offers superior efficacy and survival benefits compared with docetaxel chemotherapy. Moreover, the two therapies display distinct safety profiles, with ICI therapy associated with fewer severe hematologic toxicities.