Osteosarcoma of lumbar vertebrae in a dog

A 14 years old female Doberman dog brought for postmortem examination with a history of swelling on the back. It was revealed grossly as firm grayish-white mass and radiologically as radio opaque dense mass measuring about 18 × 14 × 14 cm in size at the level of transverse processes of 3^rd to 7^th lumbar vertebrae. Histopathological examination of the mass revealed pleomorphic round to polyhedral shaped neoplastic osteoblasts containing hyperchromatic nuclei with single nucleolus. Spicules of bone were seen. Multinucleated giant cells were found. Based on the gross, radiography and histopathological examination, the tumour mass was confirmed as osteosarcoma