title: Nasal oncocytoma in a domestic shorthair cat.
abstract: An oncocytoma was diagnosed in the nasal cavity of a 12-year-old Domestic Shorthair cat who presented with periocular swelling and sneezing. Histologic examination from biopsy material revealed monomorphic sheets, anastomosing cords, tubules, and acini composed of large polygonal to oval cells that contained abundant finely granular eosinophilic cytoplasm. No vascular or lymphatic invasions were noted. Histochemical stains revealed positive staining of tumor cells with periodic acid-Schiff (PAS) (before and after diastase digestion) and phosphotungstic acid-hematoxylin. Immunohistochemical evaluation of the tumor cells demonstrated positive staining for cytokeratin and negative staining for vimentin, desmin, S-100, glial fibrillar acidic protein, and neuronal specific enolase. Ultrastructurally, the tumor cells contained large numbers of mitochondria within their cytoplasm, which confirmed a diagnosis of oncocytoma.
authors.affiliation: PCS Biology, GE Healthcare Bio-sciences, P.O. Box 4220 Nydalen, NO-0401 Oslo, Norway. richardwilliam.doughty@ge.com
authors.forename: R W
authors.initials: RW
authors.lastname: Doughty
authors.forename: D
authors.initials: D
authors.lastname: Brockman
authors.forename: R
authors.initials: R
authors.lastname: Neiger
authors.forename: L
authors.initials: L
authors.lastname: McKinney
mesh_terms: D018249:Adenoma, Oxyphilic / Q000473:pathology / Q000662:veterinary*; D000818:Animals; D002371:Cat Diseases / Q000473:pathology*; D002415:Cats; D005260:Female; D007150:Immunohistochemistry; D009669:Nose Neoplasms / Q000473:pathology / Q000662:veterinary*