Clinical outcomes of immune checkpoint inhibitors to treat non-small cell lung cancer patients harboring epidermal growth factor receptor mutations

Background We aimed to determine the clinical. outcomes of various immune checkpoint inhibitor (ICI) combinations for the treatment of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations. The results predicted the treatment efficacy of these combinations. Methods From July 15, 2016 to March 22, 2022, 85 NSCLC patients with EGFR mutations, enrolled at the Zhejiang Cancer Hospital, received ICI combinations after resistance to prior EGFR-tyrosine kinase inhibitors (EGFR-TKIs). These patients were diagnosed with EGFR mutations using an amplification refractory mutation system PCR (ARMS-PCR) and next-generation sequencing (NGS). Survival times were analyzed using the Kaplan–Meier method and log-rank test. Results Patients who received ICIs combined with anti-angiogenic therapy had longer progression-free survival (PFS) and overall survival (OS) than patients who received ICIs combined with chemotherapy. There was no significant difference in survival time between patients who received ICIs combined with chemotherapy and anti-angiogenic therapy and patients who received ICIs combined with anti-angiogenic therapy or ICIs combined with chemotherapy, which was due to the limitation sample size of patients who received ICIs combined with chemotherapy and anti-angiogenic therapy. Patients with L858R mutations had a longer PFS and OS than patients with exon 19 deletions. T790M negative patients benefited more from ICI combinations, compared with T790M positive patients. In addition, there was no significant difference in PFS and OS between patients with TP53 co-mutations and patients without a TP53 co-mutation. We also found that patients with prior first-generation EGFR-TKI resistance had longer PFS and OS than prior third-generation EGFR-TKI resistance patients. There was no new adverse event in this study. Conclusions EGFR-mutated patients who received ICIs combined with anti-angiogenic therapy had longer PFS and OS than patients with ICIs combined with chemotherapy. Patients with L858R or without T790M mutation benefited more from ICI combinations. Besides, patients with prior first-generation EGFR-TKI resistance could benefit more from ICIs combinations than prior third-generation EGFR-TKI resistance patients.