Diagnosis:
Suggested by MRI and confirmed by pathology (brain biopsy/resection)
Pathology:
Histology: perivascular pseudoresettes (tumor cells surrounding a vessel), ependymal tubules ‘canals or rosettes’ (tumor cells lining central lumens)
Immunohistochemistry: GFAP positive, EMA dot positivity, CD99 dot positivity
Findings on Investigations:
Ventricular system infratentorial (fourth ventricle) >supratentorial >spinal (lumbosacral expansion of the cord, +/-associated syrinx, common in adults, conus medularis/filum terminale), CSF spread
Heterogenous solid mass. Cysts may occur (esp. if supratentorial). Hemorrhage & calcification may occur. Hydrocephalus.
CT:
- hypodense mass. Calcifications. Cysts may occur. Enhancement.
MRI:
- T1: hypointense.
- T2: intermediate intensity. Calcifications may be hypointense.
Treatment:
Surgical resection
Consider radiation therapy