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

/as·tro·cy·to·ma/ (as″tro-si-to´mah) a tumor composed of astrocytes; the most common type of primary brain tumor and also found throughout the central nervous system, classified on the basis of histology or in order of malignancy (Grades I–IV).

astrocytoma

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

astrocytoma

pl. astrocytomas, astrocytomata [as′trōsītō′mə]
Etymology: Gk, aster + kytos + oma
a primary tumor of the brain composed of astrocytes and characterized by slow growth, cyst formation, invasion of surrounding structures, and often development of a highly malignant glioblastoma, within the tumor mass. Complete surgical resection of an astrocytoma may be possible early in the development of the tumor. It may also be treated with radiation therapy postoperatively or if surgery is not possible. Also called astrocytic glioma.
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Astrocytoma

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]

astrocytoma (as´trōsītō´mə),

n a primary tumor of the brain composed of astrocytes and characterized by slow growth, cyst formation, invasion of surrounding structures, and often, the development of a highly malignant glioblastoma within the primary tumor mass.

astrocytoma

a common intracranial tumor composed of astrocytes; classified in order of malignancy as differentiated or undifferentiated groups.

gemistocytic astrocytoma
comprises gemistocytic astrocytes, plump or swollen astrocytes or gemistocytes.
References in periodicals archive ?
Study inclusion criteria for the astrocytoma patients included neurosurgical unit admission, surgical treatment plan, ability to consent, age 18-80 years, and no previous central nervous system (CNS) disease.
However, in most astrocytomas the mutation in the BRAF gene was different; it produced a fusion gene, designated KIAA1549-BRAF.
IDH mutations in oligodendrogliomas frequently coexist with 1p/19q deletion and in astrocytomas with TP53 mutations.
Nasdaq: THLD), today announced that the Cancer Therapy & Research Center at The University of Texas Health Science Center at San Antonio initiated a clinical trial of TH-302 in combination with bevacizumab in patients with recurrent high grade astrocytoma including glioblastoma.
Most astrocytomas are WHO grades I and II (75%) that include pilocytic and fibrillary types.
Quality of life assessments in patients who had been surgically treated for cerebellar pilocytic astrocytoma in childhood.
1), 19 commonly used reference genes were tested for their expression stability in human astrocytoma WHO Grade II, astrocytoma WHO Grade III, and glioblastoma (WHO Grade IV) both alone and compared with normal brain.
Juvenile pilocytic astrocytomas are low-grade gliomas that may affect the optic pathway (Figure 1).
This type of spread is found in low-grade tumors, like pilocytic astrocytomas, (2,3) and in high-grade tumors, like glioblastomas.
In malignant astrocytomas, more complete excision has been associated with longer survival (Levin, Leibel, & Gutin, 1997; Kaneko, 2000).
Surgical resection alone is sufficient to cure the majority of low-grade astrocytomas; however, the prognosis is not as encouraging for high-grade astrocytomas in spite of the addition of radiotherapy and chemotherapy.