The patient went on to have a resection/biopsy of the right parietal lesion. 

Histology

Sections show a moderately cellular glioma composed of cells with indistinct cell membranes, some bubbly cytoplasm, mostly in a fibrillary background. Tumor cells have irregular and elongated nuclei displaying moderate nuclear pleomorphism. Some cells are multinucleated. No palisading necrosis or microvascular proliferation is seen. Several mitoses are seen in the paraffin sections and smear. The lesion is infiltrative on NFP immunohistochemistry.

GLIOMA PANEL IMMUNOHISTOCHEMISTRY:

• GFAP: Positive
• IDH-1 R132H: Negative (non-mutated)
• ATRX: Intact (non-mutated)
• p53: Mosaic (probably not mutated)
• p16 CDKN2A: Intact
• Ki 67: 10%

DIAGNOSIS: 1-2. Anaplastic astrocytoma, IDH1 R132H immunonegative, WHO grade III

Note, in this age group the likelihood of a non-R132H IDH mutation is extremely low and sequencing is not recommended.