Efficacy of osimertinib for preventing leptomeningeal metastasis derived from advanced EGFR-mutated non-small cell lung cancer: a propensity-matched retrospective study

Background Leptomeningeal metastasis (LM) is a severe complication of advanced non-small cell lung cancer (NSCLC). This retrospective study aimed to investigate the potential use of osimertinib for preventing LM in patients with advanced epidermal growth factor receptor (EGFR)-mutated NSCLC. Methods Patients with advanced NSCLC harboring EGFR mutations who underwent tyrosine kinase inhibitors (TKIs) therapy for at least 8 weeks between September 2016 and September 2019 were eligible for this study. All included patients were divided into two groups based on whether they received osimertinib, the osimertinib group (patients treated with osimertinib) and the control group (patients not treated with osimertinib). Propensity score matching (PSM, ratio of 1:1) was used to account for differences in baseline characteristics. The cumulative incidence of LM and the overall survival (OS) were evaluated. Results A total of 304 patients were included in the study population. Among them, 116 patients received osimertinib, and 188 did not. A total of 112 patients remained in each group after PSM, and the baseline characteristics were not significantly different between the two cohorts. LM developed in 11 patients (9.82%) in the osimertinib group and 24 patients (21.42%) in the control group (hazard ratio [HR] 0.38, 95% confidence interval [CI] 0.19-0.79, p = 0.009). Multivariate analysis indicated that osimertinib was an independent, statistically significant predictor for determining the risk for LM, with an HR of 0.33 (p = 0.042). At present, the OS rate data are too immature for statistical analysis. Conclusion Real-world data demonstrate that osimertinib can significantly reduce the incidence of LM in patients with advanced NSCLC harboring common EGFR mutations. Given this result, osimertinib should be encouraged in clinical practice for specific patient populations.

Automated summary

The study found that osimertinib can significantly reduce the incidence of LM in patients with advanced NSCLC harboring common EGFR mutations. Therefore, osimertinib should be encouraged in clinical practice for specific patient populations.