Introduction . The e pidermal g rowth f actor r eceptor, or EGFR, is a transmembrane receptor tyrosine kinase (RTK), that like many other RTKs, is commonly mutated in cancer. EGFR alterations are observed in ~5% of all cancer patients, 14% of patients with non-small cell lung cancer, and 26% of patients with glioblastoma1 , 2 , 3 , 4 , 5. The use of targeted panel sequencing has helped identify multiple hotspot activating alterations in EGFR -mutant cancers, most ...