Extranodal lymphoma with peripheral nervous system involvement in a dog

Area of Science:

• Veterinary Neurology
• Veterinary Oncology
• Comparative Pathology

Background:

• Peripheral nerve tumors are uncommon in veterinary medicine.
• Neurolymphomatosis, specifically, is a rare manifestation of lymphoma in animals.

Observation:

• An 8-year-old Cavalier King Charles spaniel presented with progressive right forelimb lameness.
• Magnetic resonance imaging revealed swelling of the radial nerves and caudal brachial plexus.
• Biopsy confirmed T-cell lymphoma involving the C8 spinal nerve.

Findings:

• The T-cell lymphoma was aggressive, infiltrating the spinal cord's subarachnoid space, liver, pancreas, kidneys, and caudal thorax.
• Standard treatment with lomustine and irradiation proved ineffective.
• Neoplastic lymphocytes were identified throughout the affected organs and mass.

Implications:

• This case underscores the diagnostic and therapeutic challenges posed by neurolymphomatosis in dogs.
• Further research into rare presentations of canine lymphoma is warranted.
• Highlights the importance of considering rare differentials in neurological deficits and lameness.