Effects of Ethnicity on Outcomes of Patients With EGFR Mutation–Positive NSCLC Treated With EGFR Tyrosine Kinase Inhibitors and Surgical Resection

INTRODUCTION: In addition to the higher prevalence of EGFR mutations found among lung cancer cases in East Asian patients, it is unclear whether there are differences in treatment outcomes by ethnicity—that is, East Asian versus non–East Asian. METHODS: Patients diagnosed with EGFR-mutant lung cancer between January 2004 and October 2014 at a single center were reviewed. Data captured included demographics, tumor and treatment information, and survival. Survival of patients of East Asian and non–East Asian ancestry was compared, including in the subgroup that received EGFR tyrosine kinase inhibitor (TKI) for advanced disease and in those with early-stage disease that underwent surgical resection. RESULTS: A total of 348 patients with EGFR-mutant NSCLC were identified. There was a higher proportion of nonsmokers among those of East Asian ethnicity. No significant difference in survival was seen between patients of East Asian and non–East Asian ethnicity, median 6.7 years (95% confidence interval [CI]: 5.4–not applicable) and 5.4 years (95% CI: 4.1–7.2), respectively (p = 0.09). Among 196 patients that received treatment with EGFR TKI, the median survival from TKI initiation was also similar for those of East Asian and non–East Asian ethnicity, 3.0 years (95% CI: 2.1–3.5) and 2.7 years (95% CI: 2.2–3.5), respectively. Among the early-stage patients that underwent surgical resection (n = 163), those of East Asian ethnicity had similar median recurrence-free survival from surgery compared with non–East Asian patients, 5.3 years (95% CI: 3.5–not applicable) and 5.1 years (95% CI: 3.3–7.2), respectively. CONCLUSIONS: In a cohort of patients with EGFR-mutant lung cancer with access to uniform standards of care, East Asian ethnicity was not associated with improved survival after treatment with EGFR TKI or surgical resection.