Malignant peripheral nerve sheath tumor in a cat

A report of a cat with a cranial tumor of nerve sheath origin is presented, The cranial mass, with a cyst-like character on presentation to the referr ing veterinarian suggested,a benign lesion, but the clinical course was rap id and indicative of central nervous system involvement. The tumor was poor ly differentiated by histologic examination, but immunohistochemistry was c onsistent with Schwann cell origin. Features of peripheral nerve sheath tum ors in cats and other species are briefly discussed.