EGFR and glioblastoma: Some evidence suggests EGFRvIII is a late event human GBM: its expression is heterogeneous, and it is found on double minute chromosomes with EGFR inhibitors causing selective pressure to drive its disappearance yet unable to elicit a cure [17]; however, the EGFRvIII mutation has also been detected throughout GBMs, including regions with and without its expression, suggesting EGFRvIII may be an early event in some cases [18].