Comparative study of feline spinal cord tumors for distinction between peripheral nerve sheath tumor and meningioma.

Peripheral nerve sheath tumors (PNSTs) and meningiomas in feline spinal canal are sometimes difficult to differentiate solely on the basis of histopathology. In this study, immunohistochemical markers for differentiating PNSTs from meningiomas were investigated. In the control group, non-spinal PNSTs were immunoreactive for S100 and GFAP but not for E-cadherin, whereas intracranial meningiomas were immunoreactive for E-cadherin but not for S100 and GFAP. In the spinal tumor group, 2/7 cases were immunoreactive for S100 and GFAP but not for E-cadherin and were considered PNSTs. In addition, 5/7 cases were immunoreactive for E-cadherin and not for S100 and GFAP and were considered meningiomas. Immunohistochemistry for S100, GFAP and E-cadherin may aid in the differential diagnosis of feline spinal PNSTs and meningiomas.