Pituitary Adenoma in a dog

History: A 9.5 year old female, spayed, mixed breed dog with progressive paresis.
Gross Findings: Pituitary mass
Grossly the tumor appears hemorrhagic and more invasive than compressive but doesnt extend into very far into the thalamus.
Histopathology:
Pituitary: The neoplastic cells are variable in size and shape but do occasionally form follicles with eosinophilic colloid (PAS positive). [...]