The patient went on to have a biopsy. 

Histology

MICROSCOPIC DESCRIPTION: Paraffin sections show a mild increase in the cellularity of white matter. There is loss of normal white matter architecture and increased numbers of astrocytic cells with mild to moderate nuclear atypia. Aggregates of 3-4 astrocytic nucei are noted. There is prominent perineuronal satellitosis by atypical astrocytes in cortex. No mitotic figures are identified and there is no vascular endothelial cell proliferation and no necrosis. The features are of diffuse fibrillary astrocytoma (WHO Grade II). The Topoisomerase labeling index is approximately 1%.

FINAL DIAGNOSIS: Diffuse fibrillary astrocytoma WHO Grade II