Canine spinal nephroblastoma.

An eight-month-old, female, mixed-breed dog was presented with bilateral hind-limb paralysis that reportedly developed over a two-to-three week period and was not associated with trauma. Plain radiographs of the spinal column were unremarkable, and a myelogram outlined an intramedullary mass of the spinal cord at the first lumbar (L1) vertebra. A hemilaminectomy was performed, and a mass that was identified histologically as nephroblastoma was excised from the spinal cord. Following surgery, the dog became fully ambulatory, and at 22 months postsurgery she remains clinically normal. The diagnosis, treatment, progression, histogenesis, and pathology of canine nephroblastoma are discussed.