ATRX and astrocytoma (excluding glioblastoma): The evaluation of IDH1 and ATRX status in gliomas has both diagnostic and prognostic value as it helps in differentiating gliomas from reactive gliosis, primary glioblastoma (GB) from secondary glioblastoma, and pilocytic astrocytoma (PA) WHO grade 1 from grade 2 astrocytoma [4].