Tumor MET expression profile predicts the outcome of non-small cell lung cancer patients receiving epidermal growth factor receptor tyrosine kinase inhibitors

Background: This study assesses whether MET expression in tumor tissue is associated with an increased sensitivity to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in non-small-cell lung cancer (NSCLC) patients. Methods: This retrospective study included 69 NSCLC participants with available tumor tissue and data on treatment response and survival. MET and hepatocyte growth factor expression in tumor tissue were evaluated by immunohistochemistry. Results: Positive tMET expression correlated with a shorter progression-free survival (PFS; P = 0.003) and overall survival (OS; P = 0.05). Positive pY1234/1235 expression was significantly associated with a longer PFS (P = 0.031) and OS (P = 0.012). In multivariable analyses, tMET and pY1234/1235 expression were independent factors for PFS and OS, respectively. (tMET, PFS; P = 0.02, OS; P = 0.0007 and pY1234/1234, PFS; P = 0.01, OS; P = 0.004). Conclusions: This study suggests that total and phosphorylated MET expression in tumor tissue is potentially useful for the selection of NSCLC patients who are likely to benefit from EGFR-TKIs, irrespective of their EGFR status.