CNS tumor
Astrocytic tumors
Diffuse astrocytoma - fibrillary

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

Revised: 25 August 2017, last major update February 2012

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PubMed Search: Diffuse astrocytoma fibrillary [title]

Cite this page: Abdelzaher, E. Diffuse astrocytoma - fibrillary. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/cnstumordiffusefibrillary.html. Accessed November 24th, 2017.
Definition / general
  • Most frequent variant of diffuse astrocytoma
Microscopic (histologic) description
  • Fibrillary astrocytes with naked, atypical, elongated, irregular, hyperchromatic nuclei embedded in a fibrillary background
  • Microcysts are common
  • Some gemistocytes may be admixed
Microscopic (histologic) images

Images hosted on other servers:

Star shaped cells form felt-like perivascular mantle

All astrocytomas have a tendency to appear microcystic

Well differentiated
tumor is HAM56
negative (no
macrophages)

Positive stains
Differential diagnosis
  • Gliosis: hypertrophy of cells rather than hyperplasia, even distribution
  • Oligodendroglioma grade II: uniformly rounded nuclei with small distinct nucleoli, perinuclear halos, chicken wire vessels, calcification, GFAP negative