Ganglioglioma

From Libre Pathology
Jump to navigation Jump to search
Ganglioglioma
Diagnosis in short
LM DDx piloid gliosis, pilocytic astrocytoma, DNT
Stains PAS-D +ve (eosinophilic granular bodies)
IHC GFAP +ve, Synapto +ve
Gross usually temporal +/-cystic
Site brain - usu. supratentorial

Syndromes associated with epilepsy

Prevalence rare - esp. in children
Prognosis good (WHO Grade I)

Ganglioglioma is a epilepsy-associated glioneuronal tumour with benign course. Not to be confused with ganglioneuroma.

General

  • Gangliolioma: Grade I WHO mixed neuronal-glial tumour (ICD-O code: 9505/1).
  • Anaplastic ganglioglioma: Grade III (ICD-O: 9505/3)
  • Rare (approx. 0.5% of all CNS tumors).
  • Usu. temporal lobe.
  • Predominantly children (mean age: 9 years).
  • Recognized as a cause of epilepsy.[1]
  • Favourable prognosis (survival rates up to 97%)
    • Insufficient data für anaplastic ganglioglioma.

Imaging

  • Well-defined, T2-hyperintense.
  • Strong CM enhancement.
  • May contain cysts.
  • Associated with temporal lobe.

Gross

  • Circumscribed lesion.
  • Usu. contrast enhancing.
  • Solid, but intracortical cysts may be present.
  • Little mass effect.

Microscopic

Microscopic

Features:

  • Dysplastic neurons.
    • Out of regular architecture / abnormal location.
    • Cytomegaly
    • Clustering
    • Binucleated (very occassionally).
  • Atypical glia (ie neoplastic).
  • Eosinophilic granular bodies (more common than rosenthal fibers).
  • Dystrophic calcification.
  • Prominent capillary network.
  • Lymphocytic cuffing.
  • May contain some reticulin.
  • Glial component may resemble:
    • Fibrillary astrocytoma.
    • Oligodendroglioma.
    • Pilocytic astrocytoma.

Anaplastic ganglioglioma:

  • Brisk mitotic activity
  • Necrosis

IHC

  • Neurons:
    • MAP2 +ve
    • Synaptophysin +ve
    • Neurofilament +ve
    • Chromogranin +ve
  • Glia:
    • CD34+/-ve
  • BRAF V600E +ve (approx. 25%, mainly ganglion cells).
  • MAP2: usu. absent.
  • MIB-1 (low, but resembles proliferative tumor component).

Molecular

  • BRAF V600E-mutated(approx. 25%).
    • BRAF V600E antibody stains especially neuronal cells.
  • IDH1/2 wt.
  • No 1p/19q codeletion.
  • Usu. Chr. 7 gain.
  • CDKN2A deletions in anaplastic ganglioglioma.

Images

Prognosis

  • Good (10-year OS: 90%), but epilepsy may continue.
  • Primary treatment: surgery.

DDx:

  • DNT.
  • Oligodendroglioma.
  • Trapped cortical neurons in diffuse astrocytoma.
  • Papillary glioneuronal tumor.
  • Dysembryoplastic neuroepithelial tumor.

See also

References

  1. Im, SH.; Chung, CK.; Cho, BK.; Lee, SK. (Mar 2002). "Supratentorial ganglioglioma and epilepsy: postoperative seizure outcome.". J Neurooncol 57 (1): 59-66. PMID 12125968.