The most malignant astrocytic tumor (WHO grade IV). It is composed of poorly differentiated neoplastic astrocytes and it is characterized by the presence of cellular polymorphism, nuclear atypia, brisk mitotic activity, vascular thrombosis, microvascular proliferation and necrosis. It typically affects adults and is preferentially located in the cerebral hemispheres. It may develop from diffuse astrocytoma WHO grade II or anaplastic astrocytoma (secondary glioblastoma), but more frequently, it manifests after a short clinical history de novo, without evidence of a less malignant precursor lesion (primary glioblastoma). Two histologic variants are recognized: giant cell glioblastoma and gliosarcoma. (WHO)|Glial cell derived tumors arising from the optic nerve, usually presenting in childhood. Roughly 50% are associated with NEUROFIBROMATOSIS 1. Clinical manifestations include decreased visual acuity; EXOPHTHALMOS; NYSTAGMUS, PATHOLOGIC; STRABISMUS; pallor or swelling of the optic disc; and INTRACRANIAL HYPERTENSION. The tumor may extend into the optic chiasm and hypothalamus (MeSH).|A malignant form of astrocytoma histologically characterized by pleomorphism of cells, nuclear atypia, microhemorrhage, and necrosis. They may arise in any region of the central nervous system, with a predilection for the cerebral hemispheres, basal ganglia, and commissural pathways. Clinical presentation most frequently occurs in the fifth or sixth decade of life with focal neurologic signs or seizures (MeSH).|A malignant form of astrocytoma histologically characterized by pleomorphism of cells, nuclear atypia, microhemorrhage, and necrosis. They may arise in any region of the central nervous system, with a predilection for the cerebral hemispheres, basal ganglia, and commissural pathways. Clinical presentation most frequently occurs in the fifth or sixth decade of life with focal neurologic signs or seizures. (Experimental Factor Ontology, EFO_0000519)
1 genes associated with the glioblastoma multiforme phenotype by mapping known disease genes to disease phenotypes from the HPO Gene-Disease Associations dataset.
