Bilateral renal lymphosarcoma in a dog.

A lymphosarcoma originating from kidneys, which metastasized to the ovaries, oviducts, heart and pancreas, was pathologically diagnosed in a 3-year-old female Japanese dog (Shiba dog). Clinically, the dog exhibited vomiting, diarrhea, oliguria and abdominal enlargement, associated with hypoglycemia. Grossly, the kidneys were enlarged and neoplastic masses were also seen in the ovaries and heart. Histologically, a majority of glomeruli and renal tubules were obliterated due to diffuse invasion by tumor cells. There were no metastatic lesions in the mesenteric and tracheobronchial lymph nodes, spleen and bone marrow. Most of the tumor cells were small- to medium-sized lymphoid cells with a large nucleus and scanty cytoplasm.