Epithelioid and spindle-cell haemangioendothelioma in the brain of a dog: a case report

Abstract

A 9.5-year-old male Belgian malinois dog died after showing clinical symptoms that included fatigue, anorexia and dyspnoea. Necropsy revealed macroscopic findings in the brain and other organs. A solitary, brown-red-coloured mass, approximately 0.5 cm thick and 1.5 × 2 cm in diameter, was detected on the right side of the medulla oblongata, pons and cerebellum. The cut surface showed no invasion of the brain parenchyma. Histologically, the neoplasm was characterised by proliferation of endothelial cells, which showed epithelioid and spindle cell features. Some tumour cells had intracytoplasmic lumen formations containing red blood cells. The nuclei of the tumour cells were large and vesicular. In immunohistochemical experiments the tumour cells stained positive for factor VIII-related antigen, CD31 and CD34. A description is provided of the features of this epithelioid and spindle-cell haemangioendothelioma (EHE) that originated from vessels of the meninges in the subarachnoid space.