The pilomyxoid astrocytoma is an entity with not only pilocytic features, but also intercellular mucin and aggressive growth tendencies that distinguishes it from the more indolent pilocytic astrocytoma. (medscape.com)
The image below is an example of the histologic appearance of a pilocytic astrocytoma. (medscape.com)
Rosenthal fibers are elongated, eosinophilic, proteinaceous inclusions found in the processes of pilocytic astrocytomas. (medscape.com)
Pilocytic astrocytomas are slow growing tumors with an expansile growth pattern and little propensity to disseminate resulting, overall, in an excellent prognosis, as represented in the WHO grade (grade I). These tumors primarily arise in children and young adults but may remain asymptomatic until later in life. (medscape.com)
In contrast to the fibrillary astrocytomas, the prognosis of the brightly enhancing, exophytically growing pilocytic astrocytoma is much better. (medscape.com)
Pilocytic astrocytoma is the most common intracranial tumor in patients with neurofibromatosis type I , and these lesions are largely confined to the optic nerve. (medscape.com)
The overall incidence of pilocytic astrocytomas is 0.31 per 100,000 persons per year. (medscape.com)
[ 8 ] In the United States, pilocytic astrocytomas exhibit apparent differences in racial predisposition, with an incidence of 0.31 in white persons and 0.16 in black individuals. (medscape.com)
The clinical history of patients with pilocytic astrocytomas is usually prolonged due to the nonspecificity of the symptoms. (medscape.com)
Pilomyxoid astrocytoma (PMA) is a rare, aggressive variant of pilocytic astrocytoma (PA) that predominantly occurs in the hypothalamic chiasmatic region and is associated with shorter progression-free-survival and overall survival than PA. (aao.org)
[2] Clinicians should be aware of the neuro-ophthalmic presentations of PMA and the differences between PMA and typical juvenile pilocytic astrocytoma (JPA). (aao.org)
Variant1
[ 5 , 6 ] Similarly, the pilomyxoid astrocytoma, which is most commonly found in or around the optic chiasm and hypothalamus, has a propensity to early recurrence and infiltration, a fact that resulted in the WHO Committee upgrading this particular variant to a grade II tumor. (medscape.com)
Common2
Astrocytomas are represented by a wide variety of histologic forms and grades of tumors with a common histologic lineage. (medscape.com)
[12] [13] Although this Eyewiki will focus on signs for ophthalmology, other manifestations are common including diencephalic syndrome (DS), endocrine syndromes when present in the hypothalamus, and hydrocephalus when blocking the cerebrospinal fluid (CSF) pathway. (aao.org)
Patients with pilocytic2
The clinical history of patients with pilocytic astrocytomas is usually prolonged due to the nonspecificity of the symptoms. (medscape.com)
18. Outcome of patients with pilocytic astrocytoma and leptomeningeal dissemination. (nih.gov)
Pilocytic astrocytoma11
The pilomyxoid astrocytoma is an entity with not only pilocytic features, but also intercellular mucin and aggressive growth tendencies that distinguishes it from the more indolent pilocytic astrocytoma. (medscape.com)
The image below is an example of the histologic appearance of a pilocytic astrocytoma. (medscape.com)
In contrast to the fibrillary astrocytomas, the prognosis of the brightly enhancing, exophytically growing pilocytic astrocytoma is much better. (medscape.com)
Pilocytic astrocytoma is the most common intracranial tumor in patients with neurofibromatosis type I , and these lesions are largely confined to the optic nerve. (medscape.com)
1. Malignant transformation of a chiasmatic pilocytic astrocytoma in a patient with diencephalic syndrome. (nih.gov)
4. Pilocytic astrocytoma of the optic pathway: a tumour deriving from radial glia cells with a specific gene signature. (nih.gov)
8. [Pilocytic astrocytoma and diencephalic syndrome in an adult with neurofibromatosis type 1]. (nih.gov)
10. [Leptomeningeal spread of an intramedullary cervical pilocytic astrocytoma: case report and literature review]. (nih.gov)
14. Spinal cord pilocytic astrocytoma with leptomeningeal dissemination to the brain. (nih.gov)
19. Spinal cord pilocytic astrocytoma with cranial meningeal metastases. (nih.gov)
20. Pilocytic astrocytoma presenting as primary diffuse leptomeningeal gliomatosis: report of a unique case and review of the literature. (nih.gov)
Clinical Features1
17. Diencephalic syndrome: clinical features and imaging findings. (nih.gov)