- University of Pennsylvania
- Neurofibromas (also known as peripheral nerve sheath tumors or schwannomas) are common neoplasms of cattle which are most often seen in adult animals as incidental findings at slaughter. In cattle, the neoplasm often involves the brachial plexus and intercostal nerves; additionally, autonomic nerves of the liver, heart (epicardial plexus), mediastinum, and thorax can be affected; the most commonly affected cranial nerve is cranial nerve VIII (vestibulocochlear nerve); the skin is involved infrequently. Olfactory and optic nerves are NOT affected because they do not have Schwann cells. Affected nerves are thickened, firm, whitish gray, and may have yellow to gray nodules. Ganglia may be enlarged and appear lobulated on cut section.