Cerebrospinal fluid cytologic examination is useful in malignant astrocytomas for the detection of microscopic leptomeningeal dissemination. (medscape.com)
Brain tumor1
Astrocytoma is the most common brain tumor (see image shown below), accounting for more than half of all primary CNS malignancies in children. (medscape.com)
WHO grade I tumors include pilocytic astrocytomas and subependymal giant cell astrocytomas. (medscape.com)
Pilocytic astrocytomas (ie, WHO grade I) arise throughout the neuraxis, but preferred sites include the optic nerve, optic chiasm/hypothalamus, thalamus and basal ganglia, cerebral hemispheres, cerebellum, and brain stem. (medscape.com)
PMAs have been classified with pilocytic astrocytomas but have been found to have different histologic features and to behave more aggressively than pilocytic astrocytomas. (medscape.com)
PMAs have a tendency to disseminate and, in some reports, have a worse prognosis compared with pilocytic astrocytomas. (medscape.com)
Cord4
The brain stem and spinal cord are the next most frequently affected sites, whereas the cerebellum is a distinctly uncommon site. (medscape.com)
This report is about a 12-year-old boy with an acute and progressive course of right hemisection of the spinal cord, with ipsilateral hypo/areflexic paralysis and contralateral loss of thermalgesic sensation. (bvsalud.org)
WHO grade II tumors include diffuse astrocytomas, oligodendrogliomas and pleomorphic xanthoastrocytomas. (medscape.com)
WHO grade III tumors include anaplastic astrocytomas and anaplastic pleomorphic xanthoastrocytomas. (medscape.com)
Most astrocytomas are indolent low-grade (ie, WHO grade I-II) tumors for which surgical resection alone is sufficient to cure. (medscape.com)
The prognosis decreases for low-grade tumors in unresectable locations and remains very poor for high-grade astrocytomas in spite of the addition of radiotherapy and chemotherapy. (medscape.com)
Calcium may be present in either pineal cell tumors or astrocytomas. (medscape.com)
Diffuse2
Diffuse astrocytomas (ie, WHO grade II) may arise in any area of the CNS but most commonly develop in the cerebrum, particularly the frontal and temporal lobes. (medscape.com)
Anaplastic astrocytoma (ie, WHO grade III) arises in the same locations as diffuse astrocytomas, with a preference for the cerebral hemispheres. (medscape.com)
Arise1
Astrocytomas , which can arise from the glial stroma of the pineal gland or surrounding tissue, are also hypointense on T1 and hyperintense on T2. (medscape.com)
1. Clinicopathological features and global genomic copy number alterations of pilomyxoid astrocytoma in the hypothalamus/optic pathway: comparative analysis with pilocytic astrocytoma using array-based comparative genomic hybridization. (nih.gov)
2. Juvenile pilocytic astrocytoma 'pilomyxoid variant' with spinal metastases. (nih.gov)
10. Management of recurrent pilocytic astrocytoma with leptomeningeal dissemination in childhood. (nih.gov)
5. Pilocytic and pilomyxoid hypothalamic/chiasmatic astrocytomas. (nih.gov)
6. Intermediate pilomyxoid astrocytoma and diencephalic syndrome: imaging findings. (nih.gov)
7. Spontaneous hemorrhage associated with a pilomyxoid astrocytoma. (nih.gov)
8. Pilomyxoid astrocytomas: a short review. (nih.gov)
Brain2
Astrocytoma is the most common brain tumor (see image shown below), accounting for more than half of all primary CNS malignancies in children. (medscape.com)
Pilocytic astrocytomas (ie, WHO grade I) arise throughout the neuraxis, but preferred sites include the optic nerve, optic chiasm/hypothalamus, thalamus and basal ganglia, cerebral hemispheres, cerebellum, and brain stem. (medscape.com)
Features2
Astrocytomas comprise a wide range of neoplasms that differ in their extent of invasiveness, morphological features, tendency for progression, and clinical course. (medscape.com)
PMAs have been classified with pilocytic astrocytomas but have been found to have different histologic features and to behave more aggressively than pilocytic astrocytomas. (medscape.com)