GANGLIOCYTOMA/GANGLIOGLIOMA

WHO Grade I

Cell of Origin: Large, mature neurons +/- glial component

Common Locations: May occur anywhere in neural axis, but especially common in temporal lobe.

Demographics: May occur in any age; most common first 2 decades.

Clinical Presentation: Seizures

Histology: Gangliocytomas composed only of neuronal element. Gangliogliomas also have glial component in addition. Varied histologic appearance poorly correlated with prognosis.

Special Stains: Synaptophysin, neuron-specific enolase may verify neuronal component. Gangliogliomas will also show GFAP positivity.

Progression: Slow-growing lesion. Low malignant potential restricted to glial component of ganglioglioma.

Radiology: Well-defined solid or mixed cystic/solid mass with minimal or no mass effect. Calcification common. Enhancement pattern variable, often peripheral.

Comments: Rare association with congenital malformations such as Down's syndrome, callosal dysgenesis, and neuronal migration disorders.