Abstract:
Objective To investigate the efficacy and adverse effects of immune checkpoint inhibitor (ICI) for advanced non-small cell lung cancer (NSCLC) resistant to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI).
Methods The clinical data of 49 patients with advanced NSCLC who received ICI treatment after EGFR-TKI resistance in the Chinese People's Liberation Army General Hospital from January 2015 to March 2019 were collected. Statistical methods were used to analyze the efficacy and adverse effects of immunotherapy in patients with EGFR TKI-resistant NSCLC, and to clarify the relationship between clinical characteristics and the curative efficacy and prognosis of patients.
Results The objective response rate was significantly higher in patients with combination therapy than those with monotherapy (28.6% vs. 7.1%, P < 0.01). Patients with poor differentiation, combination therapy, and age >60 years had longer progression free survival than those with moderate differentiation (5.1 vs. 2.8 months, P=0.03), monotherapy (6.8 vs. 2.3 months, P < 0.001), and age ≤ 60 years (7.1 vs. 4.7 months, P=0.02), respectively. The overall survival of patients with combination therapy and tumor response was longer than those with monotherapy (26.9 vs. 7.1 months, P < 0.001), stable disease and progression (30.8 vs. 18.7 vs. 12.8 months, P < 0.001), respectively. Multivariate analysis showed that age >60 years and combination therapy were independent protective factors for PFS (P < 0.001). Although combination therapy group had higher overall adverse event rate than monotherapy group, there was no significant difference in the adverse reaction rate of grade 3 and above between both groups (P=0.28).
Conclusions The efficacy of monotherapy with ICI was poor in EGFR TKI-resistant patients with late-stage NSCLC, while combination therapy could significantly improve the curative efficacy and prognosis of patients. Although the overall rate of adverse events was higher in patients with combination therapy, adverse events were controllable.