EGFR and EGFRvIII expression have been shown to increase the infiltrative and invasive properties of glioma cells [24,25], therefore, one could hypothesize that patients expressing these markers may be more likely to present with multifocal disease, ependymal dissemination, or gliomatosis cerebri and perhaps this is the confounding variable between the studies accounting for the discrepancy in prognostic impact. This evidence concerns the gene EGFR and central nervous system cancer.