astrocytoma

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Related to Pilocytic astrocytoma: medulloblastoma

astrocytoma

[‚as·trə‚sī′tōm·ə]
(medicine)
A slow-growing glial tumor made up of cells resembling astrocytes; often it will undergo malignant change and assume the appearance and growth characteristics of a glioblastoma.
References in periodicals archive ?
Indeed, tumors within the LGm6 group showed a higher frequency of alterations in genes associated with pilocytic astrocytoma (recall, a noninfiltrative astrocytoma), including BRAF, NF1, and NTRAK1/2, and a lower frequency of TERT mutations compared with classical" and mesenchymal" tumors.
Cerebellar signs (28%) and papilledema (12%) were noted in pilocytic astrocytoma, medulloblastoma and haemangioblastoma; 12 of the 15 cases of Schwannoma presented with vertigo.
WHO grade I lesions, which include pilocytic astrocytomas and gangliogliomas, while WHO grade II gliomas are well circumscribed and non-infiltrative.
2) Holocord involvement typically occurs with pilocytic astrocytomas (Figure 2).
Lewis was just 20 months old when he was diagnosed with juvenile pilocytic astrocytoma – a rare, benign and slow–growing childhood brain tumour.
In this article, we present two patients (one male adolescent and one female young adult) who were diagnosed with pilocytic astrocytoma and developed cerebellar mutism after posterior fossa surgery.
We have treated cases including Glomus Jugulare, pituitary micro and macro adenomas, acoustic neuroma, schwanoma, Meningioma, metastasis, arteriovenous malformation, brain stem Glioma and recurrent GBM, Cavernous neuroma, pilocytic astrocytoma giant cell tumor etc.
They are also developing animal models of sporadic pilocytic astrocytoma for drug discovery and testing.
We report the case of a 34-year-old woman with a history of pilocytic astrocytoma resection and radiotherapy with ventriculoperitoneal shunt placement as a child who presented with altered mental status and nausea.
The most widely used system is the World Health Organization (WHO) classification (1979, 1993, 2000, and 2007) that grades astrocytomas (I-IV) based on cytological atypia, mitotic activity, vascular proliferation, and necrosis: pilocytic astrocytoma (grade I), diffuse astrocytoma (grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV).
The most common tumor was the pilocytic astrocytoma (WHO grade I), representing 31% of all cases, and it was also the most frequent tumor in all age groups, except in children less than 1 year old.