title: Pleomorphic xanthoastrocytoma, a distinctive astroglial tumor: neuroradiologic and pathologic features.
abstract: OBJECTIVE
  To analyze and discuss CT and MR features of pleomorphic xanthoastrocytoma (PXA) and present salient histopathologic features of this distinctive astroglial tumor.
  
  
  METHODS
  CT, MR, and histopathologic studies on seven patients with the histologic diagnosis of PXA were reviewed retrospectively.
  
  
  RESULTS
  All patients were in their first 3 decades of life when first diagnosed and demonstrated peripherally situated supratentorial tumors of varying size involving the superficial cortex and leptomeninges. Five of six cases examined with CT showed areas of mixed attenuation with four demonstrating well-demarcated enhancement. MR demonstrated low or mixed signal intensity on T1-weighted and high or mixed signal intensity on T2-weighted sequences. All five who received gadopentetate dimeglumine showed well-defined enhancement. Three showed cyst formation. Typical histologic features included marked cellular pleomorphism with giant cells, bizarre nuclei, variable cytoplasmic lipidization and positive immunoreactivity for glial fibrillary acidic protein. Necrosis and endothelial-pericytic cell proliferation were absent.
  
  
  CONCLUSIONS
  PXA has a highly suggestive neuroradiologic and distinctive histopathologic appearance.
authors.affiliation: Department of Radiology, University of Virginia Health Sciences Center, Charlottesville 22908.
authors.forename: M H
authors.initials: MH
authors.lastname: Lipper
authors.forename: D A
authors.initials: DA
authors.lastname: Eberhard
authors.forename: C D
authors.initials: CD
authors.lastname: Phillips
authors.forename: L G
authors.initials: LG
authors.lastname: Vezina
authors.forename: W S
authors.initials: WS
authors.lastname: Cail
mesh_terms: D000293:Adolescent; D000328:Adult; D001254:Astrocytoma / Q000175:diagnosis* / Q000473:pathology; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed