Abstract
Previous studies have demonstrated the association between EGFR mutations and distant metastasis. However, the association for subsequent brain metastasis (BM) in stages I-III non-small cell lung cancer (NSCLC) patients remains inconclusive. We conducted a retrospective analysis to clarify the impact of EGFR mutations on the incidence of BM and associated survival in patients with stage I-III NSCLC. A total of 491 patients screened for EGFR mutations were retrospectively enrolled. Brain MRI or CT was used to detect the BM. Cumulative incidence of subsequent BM and overall survival (OS) after diagnosis of BM were estimated by the Kaplan-Meier method and compared using log-rank test. We performed Cox proportional hazard regression for predictors of subsequent BM and determinants of OS after BM. The cumulative incidence of BM seemed higher in patients harboring EGFR mutations than those without EGFR mutations although it did not reach statistical significance (hazard ratio [HR] = 1.75, 95% confidence interval [CI] = 0.73~1.81). After adjusting possible confounders, including age, smoking, stage, and tumor size, EGFR mutation became one of the predictors for subsequent BM (HR = 1.89, 95% CI = 1.12~3.17, p = 0.017). Though there was no statistical difference in survival after BM between patients with EGFR mutations and wild-type EGFR (median survival: 17.8 vs. 12.2 months, HR = 0.79, 95% CI = 0.45–1.40), patients with EGFR 19 deletion (Del) tended to have a longer survival after BM than the non-EGFR 19 Del group (median survival: 29.4 vs. 14.3 months, HR 0.58, 95% CI = 0.32–1.09, p = 0.089). In conclusion, our data suggested EGFR mutation to be one of the predictors for subsequent BM in stage I-III patients. Given the small sample size, more studies are warranted to corroborate our results.
Highlights
Lung cancer is the leading cause of cancer-related deaths worldwide; in 2016, there were 158,080 lung cancer deaths in the USA alone [1]
EGFR mutation has been demonstrated to be the strongest predictor for the benefits of these EGFR-tyrosine kinase inhibitor (TKI) [3], which have shown to be superior to chemotherapy in terms of overall response rate (ORR), progression-free survival (PFS), and quality of life in untreated patients with EGFR mutation-positive non-small cell lung cancer (NSCLC) [2, 4,5,6,7,8,9,10,11]
We retrospectively reviewed and evaluated the different characteristics of brain metastasis (BM) according to the EGFR mutation status in patients with NSCLC
Summary
Lung cancer is the leading cause of cancer-related deaths worldwide; in 2016, there were 158,080 lung cancer deaths in the USA alone [1]. The impact of EGFR mutations on NSCLC patients with subsequent BM of molecular abnormalities in lung cancer has helped define disease subgroups and develop specific molecular targets in the presence of driver mutations, providing valuable information for cancer treatment. Despite advances in systemic therapy and improvements in survival for advanced NSCLC, brain metastasis (BM) remains an important cause of morbidity and mortality. The definite association for BM in early-stage NSCLC patients is not fully understood due to the small sample size and lower proportion of patients available for EGFR mutation analyses in these studies. The development of brain metastases in general predicts a poor outcome in lung cancer, it is not known whether EGFR mutation-positive patients with brain metastases have a better prognosis as compared to EGFR mutation-negative patients, especially those in stages I to III lung cancer
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
