Today’s case is a 12 year old MC Pit Bull Terrier with tetraparesis and ataxia. What are your findings?
There is focal poor detail in the dorsal and left mid-abdomen. The poor detail is caused by a soft tissue mass with areas of amorphic mineralization. The mass occupies the area of the left kidney, and no normal left kidney is visible. The mass represents a focal enlargement of the left kidney. The colon is displaced medially on the v/d projection. The liver is moderately enlarged.
- Primary neoplasia
- Metastatic neoplasia
Concurrent primary renal carcinoma and osteosarcoma (confirmed by immunohistochemistry)
This lesion has all the features of a renal mass, with location and displacement of neighboring organs, and the focal enlargement indicates a mass lesion. The final diagnosis is unusual with two apparent primary renal tumors. The osteosarcoma was responsible for the mineralization of the mass. No reason for the ataxia and paresis was found at post mortem.