Ganglioglioma
| 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.
- Eosinophilic granular bodies.
- 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
- Glia:
- CD34+/-ve
- BRAF V600E +ve (approx. 25%, mainly ganglion cells).
Molecular
- BRAF V600E-mutated(approx. 25%).
- IDH1/2 wt.
- No 1p/19q codeletion.
- Usu. Chr. 7 gain.
- CDKN2A deletions in anaplastic ganglioglioma.
Images
Lymphocytic cuffing in ganglioglioma (WC/jensflorian)
Calcification in ganglioglioma (WC/jensflorian)
CD34 immunostain in ganglioglioma (WC/jensflorian)
Pleomorphic ganglion cells in ganglioglioma (WC/jensflorian)
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.