Pleomorphic xanthoastrocytoma

What it is

A rare astrocytoma characterized by GFAP-expressing cells with nuclear/cytoplasmic pleomorphism, xanthomatous changes, and eosinophilic granular bodies surrounded by a reticulin network. Pleomorphic xanthoastrocytoma (PXA) most often has cerebral hemispheres location with meningeal involvement, mainly affects younger individuals and is frequently characterized by early seizure manifestation. Extent of resection and mitotic index are important prognostic factors. PXA commonly exhibits MAPK signaling pathway genes mutations (most frequently BRAFV600E), often combined with CDKN2A/B homozygous deletion, and a specific DNA methylation profile. The tumor corresponds to WHO grade 2 or grade 3, mainly depending on the mitotic index and Ki-67 expression.

Key facts

Prevalence

<1 / 1 000 000 (annual incidence, Europe)

Age of onset

All ages

Inheritance

Not applicable

Classified as

Disease

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

ICD-10 codes

ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.

Related health topics

Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.

Cross-references