Ataxia associated with lymphosarcoma in a dog.

A 4-year-old English Springer Spaniel with ataxia was examined because of progression of neurologic signs. Complete physical examination and results of CBC and serum biochemical analysis revealed no other abnormalities. The dog developed respiratory arrest and was euthanatized during recovery from general anesthesia, which had been performed to obtain a CSF sample. Results of CSF analysis were within reference limits. Necropsy revealed a single, well-circumscribed mass in the cerebellum, which was diagnosed as lymphosarcoma. The dog had no peripheral lymphadenopathy or organomegaly suggestive of the generalized form of the disease.