Astroblastoma

Definition

A rare central nervous system tumor characterized by a well circumscribed astrocytic neoplasm, typically arising peripherally in the frontal or parietal lobes. It usually presents in infants and young adults with symptoms of increased intracranial pressure, epileptic seizures, and/or neurological deficits. At the histomolecular level, it exhibits astroblastic perivascular pseudorosettes and positive immunostaining for GFAP and EMA. It carries fusion of MN1 with various partners (the most common being BEND2 and CXXC5) and exhibits a specific astroblastoma, MN1-altered DNA methylation class.