MedGen

A complex group of benign and malignant cerebral tumors arising at any age. [from ORDO]

An astrocytic tumor exhibiting high-grade morphological characteristics. This category includes anaplastic astrocytoma, glioblastoma, and astrocytoma, IDH-mutant, grade 4. [from NCI]

Gliomas are central nervous system neoplasms derived from glial cells and comprise astrocytomas, glioblastoma multiforme, oligodendrogliomas, ependymomas, and subependymomas. Glial cells can show various degrees of differentiation even within the same tumor (summary by Kyritsis et al., 2010). Ependymomas are rare glial tumors of the brain and spinal cord (Yokota et al., 2003). Subependymomas are unusual tumors believed to arise from the bipotential subependymal cell, which normally differentiates into either ependymal cells or astrocytes. They were characterized as a distinct entity by Scheinker (1945). They tend to be slow-growing, noninvasive, and located in the ventricular system, septum pellucidum, cerebral aqueduct, or proximal spinal cord (summary by Ryken et al., 1994). Gliomas are known to occur in association with several other well-defined hereditary tumor syndromes such as mismatch repair cancer syndrome (see 276300), melanoma-astrocytoma syndrome (155755), neurofibromatosis-1 (NF1; 162200) and neurofibromatosis-2 (see SWNV, 101000), and tuberous sclerosis (TSC1; 191100). Familial clustering of gliomas may occur in the absence of these tumor syndromes, however. Genetic Heterogeneity of Susceptibility to Glioma Other glioma susceptibilities include GLM2 (613028), caused by variation in the PTEN gene (601728) on chromosome 10q23; GLM3 (613029), caused by variation in the BRCA2 gene (600185) on chromosome 13q13; GLM4 (607248), mapped to chromosome 15q23-q26.3; GLM5 (613030), mapped to chromosome 9p21; GLM6 (613031), mapped to chromosome 20q13; GLM7 (613032), mapped to chromosome 8q24; GLM8 (613033), mapped to chromosome 5p15; and GLM9, caused by variation in the POT1 gene (606478) on chromosome 7q31. Somatic mutation, disruption, or copy number variation of the following genes or loci may also contribute to the formation of glioma: ERBB (EGFR; 131550), ERBB2 (164870), LGI1 (604619), GAS41 (602116), GLI (165220), DMBT1 (601969), IDH1 (147700), IDH2 (147650), BRAF (164757), PARK2 (602544), TP53 (191170), RB1 (614041), PIK3CA (171834), 10p15, 19q, and 17p13.3. [from OMIM]

A pilocytic astrocytoma that occurs during childhood. [from NCI]

A rare, high-grade, malignant glial tumor, histologically characterized by abundance of pleomorphic astrocytes and multiple mitotic figures, often associated with diffuse infiltration of the surrounding tissue, considerable edema and mass effect and involvement of the contralateral brain. Depending on the primary localization of the tumor, patients can present with signs of raised intracranial pressure (headache, vomiting, papilledema), seizures, progressive neurological deficits, and/or behavioral changes. The tumor is most commonly localized in the frontal and temporal lobes, brain stem and spinal cord. [from ORDO]

Astrocytoma is a neoplasm of the central nervous system derived from astrocytes. Astrocytes are a type of glial cell, and thus astrocytoma is a subtype of glioma. [from HPO]