Choroid plexus carcinoma in a cow

A red, firm 3.5x3.0x3.0cm mass was found within the right lateral ventricle, compressing the hippocampus and thalamus of the brain of a 4-year-old cow. The pituitary was enlarged and firm. Histologically, both the brain and pituitary masses consisted of moderately pleomorphic epithelial cells arranged as rosettes or sheets supported by a delicate fibrovascular stroma. Based on anatomical localization, histopathological and immunohistochemical findings, a diagnosis of choroid plexus carcinoma with pituitary metastasis was made.