EGFR and glioblastoma: Moreand more frequently, the entire cancer genome, its exome, or commonlymutated gene panels are sequenced to inform optimal treatment strategies.1−3 The epidermal growth factor receptor (EGFR) is a prominent exampleof a proto-oncogene that is frequently mutated in cancer, most notablynon-small-cell lung cancer (NSCLC) and glioblastoma.4−8 Apart from being mutated, the EGFR gene is alsofrequently amplified in a range of human tumors.8 Due to the high incidence of EGFR dysregulation in humancancer, several EGFR-targeted therapies have been approved for clinicaluse.