Michigan Veterinary Specialists, Southfield 48076-3709, USA.
A 10-year-old, intact female Brittany spaniel was presented for evaluation of progressive tetraparesis. Physical examination and diagnostic testing revealed masses within the right mammary chain and left caudal lung lobe. Neuromuscular electrodiagnostic and histopathological findings were compatible with a peripheral polyneuropathy. Upon removal of the tumors, the dog's paresis disappeared. To the authors' knowledge, this is the first reported case in the veterinary literature of improvement following therapy of a suspected paraneoplastic neuropathy.