The other case was reported as a GBM from an outside institution; the reasoning for the diagnosis was not provided, perhaps necrosis and/or microvascular proliferation was present on an alternative slide from the one we were sent or one of the other 2 GBM-defining molecular alterations (i.e. TERT promoter mutation or a gain in chromosome 7 copy number with concurrent loss of chromosome 10), was known but not provided to our institution. The gene discussed is TERT; the disease is glioblastoma.