title: Sinonasal plasmacytoma in a cat.
abstract: A 13-year-old female spayed Domestic Shorthair cat presented with a history of right-sided mucopurulent nasal discharge for 18 months. Computed tomography revealed a mass within the right nasal cavity and the right frontal sinus. The animal was euthanized, and a postmortem examination was performed. On macroscopic examination, the right nasal cavity and the right frontal sinus were partially occluded by a soft whitish mass. Microscopically, the mass was composed of well-differentiated plasma cells that were immunopositive for immunoglobulin G and lambda light chains. These findings were consistent with a mature-type sinonasal plasmacytoma. In addition, there was right-sided mucopurulent rhinitis and sinusitis caused by a Pasteurella infection, which probably developed secondary to the sinonasal plasmacytoma. To the authors' knowledge, this is the first report of a sinonasal plasmacytoma in a cat. The present communication shows that feline sinonasal plasmacytomas should be included in the differential diagnosis for tumors located in the upper respiratory tract of cats.
authors.affiliation: Department of Pathology and Infectious Diseases, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts, United Kingdom. sschoeniger@rvc.ac.uk
authors.forename: Sandra
authors.initials: S
authors.lastname: Schöniger
authors.forename: Nicole
authors.initials: N
authors.lastname: Bridger
authors.forename: Karin
authors.initials: K
authors.lastname: Allenspach
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Mantis
authors.forename: Joan
authors.initials: J
authors.lastname: Rest
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Steeves
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000175:diagnosis* / Q000473:pathology; D002415:Cats; D005260:Female; D010254:Paranasal Sinus Diseases / Q000473:pathology / Q000662:veterinary*; D010954:Plasmacytoma / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*