Survival analysis for older patients with epidermal growth factor receptor mutation-positive advanced non-small cell lung cancer after progression of first-line gefitinib

Aim Currently, little studies focus on treatment strategies and survival after progression of gefitinib in older patients with epidermal growth factor receptor )EGFR( mutant advanced non-small-cell lung cancer (NSCLC). The aim of this study was to investigate the influence of different treatment modalities on survival after progression of gefitinib in older patients. Methods This is a retrospective analysis included 62 consecutively recruited EGFR-mutant advanced NSCLC patients aged over 70 years who failed first-line gefitinib between 2008 and 2018. Kaplan-Meier method was used to estimate curves for overall survival (OS). Multivariate analysis identified independent prognostic risk factors of OS. Results The median age at diagnosis was 75 years (range, 70-88 years). The median progression-free survival of gefitinib was 11.0 months. Forty-four (69.4%) patients continued gefitinib beyond progressive disease (PD), and median gefitinib treatment duration was 18.0 months. Only 67.7% patients received anticancer treatments after discontinuation of gefitinib. The median OS was 24.5 months (95% confidence interval [CI], 19.7-29.3 months). After failure of gefitinib, the osimertinib only group had significantly improved OS compared with chemotherapy or palliative care only groups (37.5 versus 17.5 and 15.3 months, respectively; P = .017). Multivariate analysis showed that continuous gefitinib after Response Evaluation Criteria in Solid Tumor-defined PD (hazards ratio [HR] 0.273, 95% CI: 0.132-0.564, P < .001), osimertinib treatment (HR 0.244, 95% CI: 0.122-0.487, P < .001), and better performance status (HR 0.360, 95% CI: 0.163-0.796, P = .012) were significantly and independently correlated with better survival. Conclusion For older patients with EGFR-mutant advanced NSCLC, EGFR tyrosine kinase inhibitors are the most important treatment. Survival benefit of chemotherapy after failure of gefitinib seems limited.