CNS & pituitary tumors
Gliomas, glioneuronal tumors, and neuronal tumors
Other astrocytic tumors
Pleomorphic xanthoastrocytoma
Author: Eman Abdelzaher, M.D., Ph.D.
Last author update: 1 March 2012
Last staff update: 1 May 2023 (update in progress)
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Pleomorphic xanthoastrocytoma CNS
Table of Contents
Definition / general | Epidemiology | Sites | Clinical features | Radiology description | Radiology images | Case reports | Treatment | Gross description | Microscopic (histologic) description | Positive stains | Negative stains | Electron microscopy description | Differential diagnosisCite this page: Abdelzaher E. Pleomorphic xanthoastrocytoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cnstumorpleomorphicxanthoastrocytoma.html. Accessed May 30th, 2023.
Definition / general
- Astrocytic neoplasm with relatively favorable prognosis, typically in children and young adults
- First described in 1979 (Cancer 1979;44:1839)
- WHO grade II
- May be a developmental neuroglial tumor with prominent glioproliferative changes associated with focal cortical dysplasia (J Neurooncol 2004;66:17)
- Lesions with significant mitotic activity (5+ mitoses per 10 HPF) or with areas of necrosis may be designated "pleomorphic xanthoastrocytoma with anaplastic features"
Epidemiology
- Typically children and young adults but older patients may be affected
- No gender predilection
Sites
- Superficial meningocerebral location
- 98% arise supratentorially, with preferential temporal lobe involvement
- May arise in cerebellum, spinal cord and rarely in retina
Clinical features
- Associated with intractable seizures
- 15 - 20% progress to malignancy
Radiology description
- Usually cystic with a frequent cyst mural nodule architecture
Radiology images
Images hosted on other servers:
Contrast enhanced axial CT image
Superficial tumor
Case reports
- 32 year old man whose tumor had pigmented melanotic cells (Arch Pathol Lab Med 2001;125:808)
- 43 year old woman with rare anaplastic variant (Neuropathology 2005;25:241)
- 49 year old man with seizures (Arch Pathol Lab Med 2003;127:e307)
- 60 year old man with coexisting ganglioglioma in cerebellum (Arch Pathol Lab Med 2000;124:1707)
Treatment
- Gross total resection usually eliminates seizures
Gross description
- Mainly superficial with leptomeningeal involvement
- Usually cystic
Microscopic (histologic) description
- Key histopathological features are usually seen in superficial compact component of tumor, including pleomorphic cells (mono or multinucleated with frequent nuclear inclusion and occasional cytoplasmic xanthomatous change), spindle cells arranged in fascicular pattern
- Other features include perivascular lymphocytic cuffing, scattered eosinophilic granular bodies, reticulin rich network
- Underlying cortex shows infiltrative astrocytic component
- Variable hemorrhage and protein granular degeneration (similar to pilocytic astrocytoma)
- No necrosis and no mitotic activity, except in tumors "with anaplastic features"
Positive stains
- GFAP and S100 (Am J Surg Pathol 2002;26:479, Arch Pathol Lab Med 2003;127:1187)
- Reticulin, class III beta tubulin (73%)
- Variable expression of neuronal markers including synaptophysin
Negative stains
- Chromogranin, p53 (or focal)
Electron microscopy description
- Tumor cells are surrounded by basal lamina; neuronal features of microtubules, dense core granules
Differential diagnosis
- Glioblastoma and giant cell glioblastoma
- Malignant fibrous histiocytoma
- Other cystic lesions:
especially those with a cyst mural nodule architecture (pilocytic astrocytoma and ganglioglioma)
