obsolete_astrocytic tumor true NCIt:C6958 Neoplasms of the brain and spinal cord derived from glial cells which vary from histologically benign forms to highly anaplastic and malignant tumors. Fibrillary astrocytomas are the most common type and may be classified in order of increasing malignancy (grades I through IV). In the first two decades of life, astrocytomas tend to originate in the cerebellar hemispheres; in adults, they most frequently arise in the cerebrum and frequently undergo malignant transformation. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2013-7; Holland et al., Cancer Medicine, 3d ed, p1082) 1.5 MESH:D001254 http://purl.obolibrary.org/obo/MONDO_0019781 true SNOMEDCT:38713004 Duplicate with astrocytic tumor (EFO_0000272) James Malone A glial tumor of the brain or spinal cord showing astrocytic differentiation. It includes the following clinicopathological entities: pilocytic astrocytoma, diffuse astrocytoma, anaplastic astrocytoma, pleomorphic xanthoastrocytoma, subependymal giant cell astrocytoma, and glioblastoma. DOID:3069 SNOMEDCT:254938000