Exclusion of Histiocytes/Endothelial Cells and Using Endothelial Cells as Internal Reference Are Crucial for Interpretation of MGMT Immunohistochemistry in Glioblastoma

We evaluated the predictive value of O6-methylguanine-DNA methyltransferase (MGMT) protein expression and MGMT promoter methylation status in glioblastomas (GBM) treated with temozolomide (TMZ) in a Taiwan medical center. Protein expression by immunohistochemical analysis (IHC) and MGMT promoter met