EGFR mutation is not a prognostic factor for CNS metastasis in curatively resected lung adenocarcinoma patients

Introduction: For NSCLC patients with complete resection, the prognostic role of EGFR mutation for recurrence, especially for CNS metastasis, is still controversial. In this study, we aimed to identify the characteristics of the recurrence pattern of lung adenocarcinoma based on EGFR mutation status.

Methods: Overall, 888 patients with completely surgically resected LUAD who underwent EGFR mutation status analysis from two Chinese institutions were included. Sites and data of initial recurrence were recorded. The recurrence patterns according to EGFR mutation status were estimated by Kaplan-Meier analysis, and hazard rate curves were generated.

Results: 245 (27.6%) of 888 patients suffered from recurrence. Before and after PSM, there were no statistically significant differences between the EGFR mutation and EGFR WT groups for all types of recurrence, including CNS metastasis. Multivariable Cox analysis revealed that EGFR status was not a risk factor for all types of recurrence, including CNS metastasis (HR 0.88, 95% CI 0.54-1.46, p = 0.632). The CNS metastasis hazard curve in the EGFR mutation group showed that the first peak occurred at approximately 24-26 months after surgery, which was 10 months later than that in the EGFR WT group. In addition, the second peak time in the EGFR mutation group was approximately 2 years later than that in the EGFR WT group.

Conclusions: EGFR mutation was not an independent prognostic factor for postoperative recurrence. EGFR-mutated LUADs did not have a clinical course with a higher incidence of CNS metastasis. However, the peak hazards for recurrence of CNS metastasis occur at a later time point in the EGFR mutant group compared with the EGFR wild type group.