Meningeal osteosarcoma in a dog’s brain

Abstract

Osteosarcoma is the most common bone cancer in dogs. It has a high invasion capacity, commonly metastasize and it mainly arises in the medullary canal of long bones of the appendicular and axial skeleton, rarely affecting primarily extra-skeletal sites. Osteosarcoma of primary meningeal origin is extremely rare in human and veterinary medicine. A male, mixed breed dog was admitted at the Veterinary Hospital with a history of being overly excited, having decreased neurological reflexes and development of seizures. As the situation evolved, the animal was euthanized. The animal was referred to the Veterinary Pathology Service for necroscopic examination. The objective of this report was to describe a case of primary extra-skeletal osteosarcoma of the meninges in a dog, which presented clinical signs compatible with a disease originating in the central nervous system and which was diagnosed by histopathological and immunohistochemical analysis.