The patient went on to have a craniotomy and debulking of the tumour. 


Frozen section diagnosis: Left lateral ventricular tumor: Malignant neoplasm, differential between choroid plexus carcinoma and atypical teratoid rhabdoid tumor and anaplastic ependymoma.

Immunohistochemistry: CTK+, EMA+, GFAP+, NFP-, VIMENTIN+, SYNAPTOPHYSIN+, CD56 focal, BAF-47 absent, SMA+

Electron Microscopy: EM07-513

FINAL DIAGNOSIS: Atypical teratoid / rhabdoid tumour (AT/RT)