Clinical Predictive Factors associated with First Line EGFR-TKI Efficacy in Advanced NSCLC Patients with EGFR Mutations

Abstract

Background and objective Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have demonstrated some dramatic efficacy in advanced non-small-cell lung cancer (NSCLC) patients with activating EGFR mutation. However, progression-free survivals (PFS) among those patients who were treated with first line EGFR TKIs were inconsistent. The aim of this study is to explore the association of clinical prognostic factors with EGFR-TKI efficacy in advanced NSCLC patients. Methods The demographic and clinical characteristics of 203 patients with activating EGFR mutation treated with first generation TKI as a first-line therapy were retrospectively reviewed. Results Of the 203 patients enrolled in this study, 139 patients had progression of disease and 63 patients died. The subjects had a median follow up duration of 21.1months and a median PFS of 14.3 months. Partial response (PR) was achieved in 127 (66.1%) patients and stable disease (SD) rate was achieved in 55 (28.6%) patients. In univariate analysis, patients with 2 or higher ECOG score (5.1 vs 16 months, P=0.033), SD as best overall response (9.5 vs 17.9 months, P=0.030), extrathoracic metastasis (11.7 vs 27.5 months, P=0.004), liver metastasis (4.1 vs 16.0 months, P=0.000), bone metastasis (13.3 vs 21.5months, P=0.027) and pulmonary embolism (5.5 vs 16.6 months, P=0.005) had shorter PFS than those without the listed factors. Multivariable Cox regression analysis showed best overall response (HR=1.825, 95%CI: 1.107-3.008, P=0.018) and liver metastasis (HR=1.694, 95%CI: 1.146-5.756, P=0.022) were independent predictive factors of shorter PFS. Conclusion Despite the high efficacy of EGFR-TKI, SD as best overall response and liver metastasis predicts poorer PFS in advanced NSCLC patients with EGFR gene mutations receiving first-line therapy treatment.

DOI: 10.3779/j.issn.1009-3419.2019.02.04