Efficacy and Prognosis of First-Line EGFR-Tyrosine Kinase Inhibitor Treatment in Older Adults Including Poor Performance Status Patients with EGFR-Mutated Non-Small-Cell Lung Cancer

Introduction: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are standard first-line treatments for advanced EGFR-mutated non-small-cell lung cancer (NSCLC) patients. The efficacy of EGFR-TKIs in older patients including poor Eastern Cooperative Oncology Group (ECOG) performance status (PS) is seldom investigated. Methods: We enrolled patients 65 years or older with EGFR-mutated Stage IIIB-IV NSCLC and evaluated the efficacy and prognosis of first-line EGFR-TKI treatment. Clinical and demographic characteristics were reviewed and analyzed, including age, sex, PS, smoking history, EGFR mutation type, treatment regimen, progression-free survival (PFS), and overall survival (OS). Results: From January 2015 to December 2019, a total of 237 patients were included, 205 of whom were eligible for efficacy and outcome analyses. Among them, 91 (44.4%) were categorized as poor PS (2-4). Compared with patients categorized as good PS (0-1), those with poor PS were older (79 versus 75 years), had a higher proportion of brain metastases (41.8% versus 25.4%), more comorbidities (74.7% versus 54.4%), and more likely to be treated with first-generation TKIs (74.7% versus 57.0%). The PFS and OS were 17.1 and 26.7 months respectively in patients with good PS and 12.7 and 18.2 months in those with poor PS (both p < 0.001). In the multivariate analysis, good PS, <3 metastatic sites, and first-line treatment with afatinib compared with erlotinib and gefitinib were associated with longer PFS. A relatively younger age, good PS, < 3 metastatic sites, and no brain metastasis at diagnosis were associated with better OS. Conclusion: In older patients with EGFR-mutated NSCLC and receive EGFR-TKI treat-ment, a good PS and <3 metastatic sites at diagnosis were associated with a longer PFS and OS. In addition, afatinib as first-line treatment was associated with a longer PFS whereas a relatively younger age and no brain metastasis at diagnosis were associated with better OS.