The significant WT1 expression differences between diffuse astrocytomas, oligoastrocytomas and oligodendrogliomas, which are also present in the Repository for Molecular Brain Neoplasia Data, National Cancer Institute (REMBRANDT, 2005, http://rembrandt.nci.nih.gov) gene database set, provide a rationale for use of WT1 as part of a routine immunohistochemistry panel.