The most common mutant of EGFR, EGFRvIII, which results from a deletion of the extracellular amino acids 6 to 273 (exons 2 to 7), occurs at an overall frequency of 25–64% when assessed by multiple techniques in GBM [4] and contributes to constitutively active oncogenic signaling that correlates with worse prognosis [5]. The gene discussed is EGFR; the disease is glioblastoma.