IDH1 and oligodendroglioma: These markers group LGG as IDH mutated, 1p/19q co-deficient or 1p/19q preserved, TERT mutated or P53 and ATRX mutated oligodendroglioma cell tumors or astrocytomas; simple TERT mutations and triple-negative tumors, including oligodendroglioma or astrocytoma with no IDH mutation, no co-deletion of 1p/19q and no TERT mutation that is not associated with IDH mutation [29].