CNS tumor

Neuronal and mixed neuronal-glial tumors

Extraventricular neurocytoma

Topic Completed: 1 January 2006

Minor changes: 1 September 2020

Copyright: 2002-2021,, Inc.

PubMed Search: Extraventricular neurocytoma [title]

Nat Pernick, M.D.
Page views in 2020: 812
Page views in 2021 to date: 741
Cite this page: Pernick N. Extraventricular neurocytoma. website. Accessed October 22nd, 2021.
Definition / general
Radiology description
  • Circumscribed, solitary and 57% cystic
Prognostic factors
  • Poor prognostic factors: incomplete excision, atypical features, high cell proliferation rates; also older patient age
Case reports
  • Total excision prevents recurrence
Microscopic (histologic) description
  • Sheets, clusters, ribbons or rosettes of monotonous tumor cells with round and regular vesicular nuclei and distinct nucleoli embedded in matrix of fine neuropil
  • Ganglion cells in 66%
  • Atypical if necrosis, vascular proliferation and 3+ mitotic figures/10 HPF
Positive stains
  • Synaptophysin (strong), GFAP (46%; also is staining of entrapped astrocytes at periphery)
Electron microscopy description
  • Neuritic type processes with microtubules, dense core granules
Differential diagnosis
  • Ependymoma
  • Oligodendroglioma: no ganglion cell differentiation, no salt and pepper chromatin and no neuropil islands; usually more infiltrative, synaptophysin-
Back to top
Image 01 Image 02