title: Malignant epithelioid schwannoma affecting the trigeminal nerve of a dog.
abstract: A malignant epithelioid schwannoma was diagnosed affecting the trigeminal nerve of an 11-year-old dog. Neurologic abnormalities included an altered mental status, ataxia, left head tilt, postural reaction deficits of all four limbs, a pronounced left masticatory muscle atrophy, and absent left facial sensation. Histologically, a densely arranged epithelioid population with a very high mitotic index was surrounded by a spindle-shaped cell proliferation characteristic of schwannomas. Both cell populations stained positively for vimentin, but only spindle cells were occassionally positive for S-100 protein. The histologic and immunohistochemical features of this tumor were consistent with those found in human epithelioid schwannomas.
authors.affiliation: Department of Pathology and Animal Production, School of Veterinary Medicine, Campus UAB, Bellaterra, Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Pumarola
authors.forename: S
authors.initials: S
authors.lastname: Añor
authors.forename: D
authors.initials: D
authors.lastname: Borràs
authors.forename: I
authors.initials: I
authors.lastname: Ferrer
mesh_terms: D000818:Animals; D004285:Dogs; D015622:Epithelioid Cells / Q000473:pathology*; D007150:Immunohistochemistry; D009442:Neurilemmoma / Q000276:immunology / Q000473:pathology* / Q000662:veterinary; D010524:Peripheral Nervous System Neoplasms / Q000276:immunology / Q000473:pathology* / Q000662:veterinary; D009418:S100 Proteins / Q000032:analysis; D014276:Trigeminal Nerve / Q000473:pathology*; D014746:Vimentin / Q000032:analysis
chemical_list: D009418:S100 Proteins; D014746:Vimentin