The mass was resected and microscopic description revealed:

Sections of the brain reveal a neoplastic tissue with marked nuclear crowding and atypia, mitotic activity, microvascular proliferation, and palisading necrosis. also in a focus presence of fried-egg patterns delineate chicken wire network of capillaries is noted.

Diagnosis: Glioblastoma with an oligodendroglial component.

IHC results:

Strongly cytoplasmic immunoreactivity of tumor cells. 

Final diagnosis: 

IDH mutant glioblastoma(secondary glioblastoma)