Peripheral neuropathy associated with malignant neoplasms in dogs

Area of Science:

• Veterinary Neurology
• Oncology
• Pathology

Background:

• Paraneoplastic syndromes can affect the nervous system in cancer patients.
• Subtle neurological changes may occur in dogs with malignant tumors.

Purpose of the Study:

• To investigate subclinical paraneoplastic effects on peripheral nerves in dogs with malignant tumors.
• To determine the incidence and characteristics of nerve abnormalities in dogs with cancer.

Main Methods:

• Examination of common peroneal and ulnar nerves from 21 dogs with malignant tumors (ages 2-15 years).
• Single-teased fiber studies were performed to assess nerve fiber integrity.
• Abnormalities were compared to age-matched control dogs.

Main Results:

• Nerve abnormalities were detected in 76% of dogs with malignancies, exceeding control limits.
• The common peroneal nerve (73% incidence) showed more abnormalities than the ulnar nerve (57%).
• Lesions included demyelination/remyelination and axonal degeneration, with demyelination predominating.

Conclusions:

• Malignant tumors in dogs are associated with a high incidence of subclinical peripheral neuropathy.
• The common peroneal nerve is more susceptible to paraneoplastic changes.
• Neuropathy severity varied with tumor type, with bronchogenic carcinoma and mammary adenocarcinoma showing the most severe lesions.