CNS tumor
Astrocytic tumors
Gliosarcoma

Author: Eman Abdelzaher, M.D., Ph.D. (see Authors page)

Revised: 25 August 2017, last major update March 2012

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Gliosarcoma CNS

Cite this page: Abdelzaher, E. Gliosarcoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/cnstumorgliosarcoma.html. Accessed November 19th, 2017.
Definition / general
  • Rare biphasic subtype of glioblastoma, with alternating glial and mesenchymal differentiation (glioblastoma and sarcoma)
  • WHO grade IV
  • May be well circumscribed and resemble meningioma radiologically
  • May progress to pure sarcoma (GFAP-)
  • Rarely expresses epithelial markers or lipid
Radiology description
  • Predominantly sarcomatous tumors appear well demarcated with homogeneous contrast enhancement, may mimic meningioma
Radiology images

Images hosted on other servers:

MR images

Various images

Before surgery

Case reports
Gross description
  • Firm, well circumscribed mass (resembling meningioma or metastasis)
Microscopic (histologic) description
  • Glioblastoma (occasionally oligodendroglioma, rarely ependymoma) plus regions of sarcoma resembling fibrosarcoma or malignant fibrous histiocytoma rich in reticulin (collagen+, GFAP-)
Microscopic (histologic) images

Images hosted on other servers:

Various images

With prominent smooth muscle component

Reticulin stain

EGFR, p53

With carcinomatous areas


2A: Biphasic with epithelioid and spindle cells
2B: Markedly increased nuclear Ki67 staining
2C: Epithelioid component has strong GFAP staining
2D: Spindle cells SMA+, surrounded by reticulin fiber

Cytology description
  • Highly cellular
  • High grade tumor with mesenchymal and glial components
  • Mesenchymal features may be fibrosarcoma, rhabdoid, osteoclastic giant cell, undifferentiated or heterologous elements
  • Rich arborizing vessels, high mitotic rate, necrosis
  • Glial component has pleomorphic round / oval nuclei, gemistocytes in fibrillary stroma (Diagn Cytopathol 2004;30:77)
Differential diagnosis
  • Glioblastoma: may have desmoplasia but spindled areas lack features of malignancy