Association of brain metastasis in non-small cell lung cancer.

Abstract

e19081 Background: Brain metastases are the main cause of non-small cell lung cancer (NSCLC) relapse and death. However, it is difficult to predict which NSCLC patient will develop brain metastasis. We have observed and summarized the relationship between the clinical and molecular biological features including EGFR mutation status and brain metastases in a prospectively enrolled case series, and developed a multivariable model in this study. Methods: The study enrolled 184 Chinese NSCLC patients with at least 18 months follow-up period. Clinical information including age, smoking history, lymph node status, pathological stage, primary location and histological type of the tumor and EGFR (including exon 19 and 21) and KRAS mutation status were collected and analyzed. Univariate and multivariate Cox regression analysis was run to investigate risk factors of brain metastasis from these features. A risk model based on these risk factors was constructive. Results: 13.0% (24/184) patients were diagnosed as brain metastasis. EGFR mutation (P=0.026), younger age (P=0.034) and lymph node metastasis (P=0.038) were associated with brain metastasis. A Cox model based on these 3 factors was founded and the risk of brain metastasis was 1.9% (1/53), 8.3% (5/60) and 25.4 % (18/71) in low, intermediate and high risk group, respectively (P<0.001). Conclusions: EGFR mutation, younger age and lymph node metastasis are associated with brain metastasis in NSCLC patients. If confirmed in clinical trials, high risk patients may be considered for prophylactic cranial irradiation therapy in future clinical trials