title: Gliosarcoma with features of chondroblastic osteosarcoma.
abstract: BACKGROUND
  The occurrence of osteoid-chondral elements in gliosarcoma is extremely rare and has been reported in only two cases. A new, rare case of gliosarcoma with osteosarcomatous differentiation in a 55-year-old man and histogenesis of osteoid-chondral tissue in gliosarcoma is discussed.
  
  
  METHODS
  Surgically removed tumor tissues were examined immunohistochemically and electron microscopically, and a histologic examination was performed.
  
  
  RESULTS
  Immunohistochemical and electron microscopic studies confirmed the presence of glial, fibroblastic, and osteoid-chondral elements. A major part of the sarcomatous tissue was undifferentiated and stained only by vimentin. Some areas of osteoid-chondral tissue were positive for glial fibrillary acidic protein (GFAP).
  
  
  CONCLUSIONS
  These data suggest that osteoid-chondral elements came from the sarcomatous portion and GFAP positivity is not restricted to astrocytes and has been seen particularly in chondroid areas of non-glial tumors.
authors.affiliation: Second Department of Pathology, Okayama University Medical School, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: N
authors.initials: N
authors.lastname: Ohara
authors.forename: H J
authors.initials: HJ
authors.lastname: Jeon
authors.forename: S
authors.initials: S
authors.lastname: Akagi
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Akagi
authors.forename: S
authors.initials: S
authors.lastname: Namba
mesh_terms: D001932:Brain Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D002471:Cell Transformation, Neoplastic; D002804:Chondroblastoma / Q000737:chemistry / Q000473:pathology*; D005625:Frontal Lobe / Q000473:pathology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D005910:Glioma / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D008297:Male; D008875:Middle Aged; D012516:Osteosarcoma / Q000737:chemistry / Q000473:pathology*
chemical_list: D005904:Glial Fibrillary Acidic Protein