Characterize the Different Types of Brain Tumors in Children and Adults

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The Answer is The classification of primary brain tumors is based upon the cell of origin. Tumors arising from glial cells (neuroglia) are called gliomas, those arising from neurons are called neuromas or neuroblastomas, and tumors arising from meningeal cells are called meningiomas. Gliomas and meningiomas account for approximately two thirds of all tumors that arise in the brain.
Glioma is a cancer that arises from the glial cells (glia) of the brain. Glia are crudely divisible by size into macroglia and microglia. Macroglia are further categorized as astrocytes and oligodendrocytes. Astrocytes nurture and support neurons, and their tentacle-like processes encircle and envelop the synapses between nerve cells, supplying energy and oxygen necessary for the transmission of nerve impulses. Oligodendrocytes are macroglia that produce and secrete myelin, the insulatory material of neurons.
Glioma tumors are further classified by glial cell type into astrocytomas, glioblastoma multiforme, oligodendrogliomas, ependymomas, and mixed gliomas. Glioblastoma Multiforme is the most common and most aggressive type of glioma. Patients diagnosed with glioblastoma have a median survival time of less than one year. Approximately 50-60% of gliomas are classified as glioblastoma.
Astrocytomas account for 20-30% of all gliomas. These tumors arise from astrocytes or their precursor cells. As their name implies, astrocytes are star-shaped cells that perform multiple functions including support of endothelial cells of the blood brain barrier, provision of nutrients and energy to neurons and maintenance of their ionic balance, and repair of nerve tissues following traumatic injury.
Ependymomas account for about 6% of all gliomas. They arise from the layer of neuroepithelial cells that line both the hollow cavities of the brain and the canal containing the spinal cord. Within the brain, ependymomas most often arise from the floor of the fourth ventricle, situated in the lower back portion of the brain.
Oligodendrogliomas account for less than 5% of all gliomas. They arise from the oligodendrocytes, glial cells that are primarily responsible for laying down myelin around axons of neurons.

Characterize the Different Types of Brain Tumors in Children and Adults

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