astrocytoma

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astrocytoma

 [as″tro-si-to´mah]
a tumor composed of astrocytes; classified in order of malignancy as: Grade I, consisting of fibrillary or protoplasmic astrocytes; Grade II (astroblastoma); Grades III and IV (glioblastoma multiforme).

as·tro·cy·to·ma

(as'trō-sī-tō'mă),
A glioma derived from astrocytes.
[G. astron, star, + kytos, cell, + -oma, tumor]

astrocytoma

(ăs′trō-sī-tō′mə)
n. pl. astrocyto·mas or astrocyto·mata (-mə-tə)
A malignant tumor of nervous tissue composed of astrocytes.

as·tro·cy·to·ma

(as'trō-sī-tō'mă)
A glioma derived from astrocytes; in people younger than 20 years of age, usually arise in a cerebellar hemisphere; in adults, usually occur in the cerebrum, sometimes growing rapidly and invading extensively.
[G. astron, star, + kytos, cell, + -oma, tumor]

astrocytoma

A tumour derived from the supporting tissue of nerve cells (neuroglia). The astrocytoma varies widely in malignancy and rate of growth.

as·tro·cy·to·ma

(as'trō-sī-tō'mă)
A glioma derived from astrocytes; in people younger than 20 years of age, usually arise in a cerebellar hemisphere; in adults, usually occur in the cerebrum, sometimes growing rapidly and invading extensively.
[G. astron, star, + kytos, cell, + -oma, tumor]
References in periodicals archive ?
Astrocytomas routinely do not require treatment and the lesion will continue to be monitored to ensure that it does not increase in size or character.
The pilocytic variant of glioma (astrocytoma) usually affects childhood or early adolescents and is benign and noninvasive in nature [6-8].
Meyer et al., "Analysis of BRAF V600E mutation in 1,320 nervous system tumors reveals high mutation frequencies in pleomorphic xanthoastrocytoma, ganglioglioma and extra-cerebellar pilocytic astrocytoma," Acta Neuropathologica, vol.
Variations in the natural history and survival of patients with supratentorial low-grade astrocytomas. Neurosurgery 1996; 38: 872-9.
Keywords: Angiomyolipoma, rhabdomyoma, subependymal giant cell astrocytoma, tuberosclerosis, tumor
Survival curves show a poor survival experience within the first few years of diagnosis for gliomas (NOS), diffuse astrocytomas, anaplastic astrocytomas and GBM, and a better survival experience for oligoastrocytic tumours, anaplastic oligodendrogliomas, oligodendrogliomas and all other tumours.
In this presentation, clinical and radiological findings of subependymal giant cell astrocytoma and cortical tubers leading to new onset seizures will be discussed.
Astrocytomas tend to expand the cord eccentrically (Figure 1).
Regarding the clinical spectrum of tuberous sclerosis it was seen that epileptic fits and cardiac complications were seen in 50% patients each eye abnormalities including retinal astrocytomas were seen in 40% patients mental retardation was seen in 25% patients followed by astrocytomas and pulmonary disease seen in 20% patients each.
The most common types of brain tumour in children are astrocytomas, medulloblastomas, ependymomas and brain stem gliomas.
(1) Surgery is the cornerstone of treatment for the majority of low-grade astrocytomas, while postoperative radiotherapy has been shown to lengthen the progression-free period without significantly affecting the overall survival - median survival is 7.2 - 7.4 years.