Expression of c-MET in invasive meningioma

Background: Meningiomas show high recurrence rates even after curative tumor removal. The invasiveness of meningiomas may contribute to their high recurrence rates. Recently, c-MET and hepatocyte growth factor (HGF) have been reported to be involved in cancer invasion. Methods: We examined the immunohistochemical expression of c-MET and HGF in 100 cases of patients with meningiomas who have undergone complete tumor removal. Results: c-MET^-High and HGFHigh were found in 17% and 13% of meningiomas, respectively. Brain invasion was observed in 17.6% of c-MET^-High meningiomas, but in only 2.4% of c-MET^-Low meningiomas (p=.033). Bone/ soft tissue invasion was observed in 23.5% of c-MET^-High meningiomas and in 9.6% of c-MET^-Low meningiomas (p=.119). HGF^-High did not show statistical association with brain invasion or bone/ soft tissue invasion. c-MET^-High demonstrated shorter recurrence-free survival (RFS, 93.5±8.2 months vs 96.1±1.9 months); however, this difference was not statistically significant (p=.139). There was no association of HGF^-High with RFS. Conclusions: This study demonstrates that c- MET^-High is associated with brain invasion of meningiomas, and that c-MET expression may be a useful predictive marker for meningioma recurrence. Patients with invasive meningiomas with high expressions of c-MET may be good candidates for targeted therapy using c-MET inhibitors.