Aberrant EGFR signaling drives GBM glycolysis,2,19 raising the potential for 18F-FDG PET to serve as a non-invasive imaging surrogate for EGFR TKI tumor pharmacodynamics and as a predictive response biomarker in GBM patients.22 Osimertinib is a clinically approved drug for the treatment of EGFR-mutant NSCLC, due to the ability of it to inhibit the EGFR kinase found in these tumors. The gene discussed is EGFR; the disease is glioblastoma.