The patient went on to have a craniotomy and resection of the mass.
Histology
MICROSCOPIC DESCRIPTION: The sections show somewhat lobulated fragments of moderately cellular glial tumour. The tumour cells show prominent clustering. They have round to ovoid nuclei with no significant nuclear pleomorphism. There is microcystic change in the background. No mitoses, endothelial cell hyperplasia or necrosis is identified. No evidence of metastatic carcinoma is seen. The features are those of a subependymoma.
FINAL DIAGNOSIS: Right frontal horn tumour subependymoma (WHO Grade I).