Dysembryoplastic neuroepithelial tumor DNET

WHO grade I

Diagnosis:

Suggested by MRI and confirmed by pathology (brain biopsy/resection)

Findings on Investigations:

MRI: Intracortical lesions, commonly in the temporal lobe, may have a small cystic component

Clinical features:

Associated with intractable seizures in some cases

Pathology:

Histology: Nodular or multinodular. Mucin rich cortical nodules
Oligodendroglial-like areas (halos without satellitosis) and neurocytic areas. ‘specific glioneuronal element’: oligodendroglial-like cells  with axons around microcystic spaces with ganglion cells.  Floating neurons= ganglion cells in a pool of mucin
Dysplastic adjacent cortex. Calcifications & cysts may occur.
Immunohistochemistry: synaptophysin positive, S100 oligodendroglial-like cells positive, GFAP negative, MIB low.

Treatment:

Surgical resection

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