EP1.14-22 Amplification and Overexpression of MET in Brain Metastases of Non-Small Cell Lung Cancer

Abstract

Non-small-cell lung carcinoma (NSCLC) with MET amplification may respond to c-MET inhibitors. We investigated MET gene amplification status by fluorescence in-situ hybridization (FISH) and c-MET protein expression by immunohistochemistry of 42 NSCLC brain metastases (34 adenocarcinoma, 4 squamous cell carcinoma, 4 NSCLC-NOS). We found MET gene amplification in 7/42 (21.6%) and c-MET protein expression in 9/42 (21%) of evaluable brain metastasis. There was no correlation between the presence of MET gene amplification and c-MET protein expression (p<0.1, Chi square test). One patient with MET amplification also had EGFR mutation. Three patients with c-Met overexpression had ALK rearrangement. c-MET overexpression and MET amplification are commonly found in brain metastasis of NSCLC and may represent a promising therapeutic target.