title: Penile extramedullary plasmacytoma in a dog.
abstract: Penile tumours are rare in dogs. Reported herein is a case of a penile extramedullary plasmacytoma (EMP) in a 5-year-old male cocker spaniel that was brought to a local hospital for an evaluation of a penile mass. The mass was approximately 1.3 cm in diameter at the time of presentation. In fine needle aspiration and histopathological examinations, the neoplastic cells showed eccentric round nuclei, a moderate amount of basophilic cytoplasm, and a peri-nuclear clear zone, consistent with plasma cell morphology. There was nuclear pleomorphism with mononuclear giant cells and occasional bi-nucleation. Round cells on the periphery of the mass demonstrated plasmacytic differentiation. Immunohistochemically, the neoplastic cells stained positive for MUM1 and light lambda chain. Based on the cytological and pathological observations, a diagnosis of penile EMP was established.
authors.affiliation: 1Department of Veterinary Surgery, College of Veterinary Medicine, Chonbuk National University, Jeonju, Korea.
authors.forename: Min-Su
authors.initials: MS
authors.lastname: Kim
authors.forename: Dong Hoo
authors.initials: DH
authors.lastname: Kim
authors.forename: Ul Soo
authors.initials: US
authors.lastname: Choi
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000473:pathology* / Q000601:surgery; D004285:Dogs; D008297:Male; D010412:Penile Neoplasms / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D010954:Plasmacytoma / Q000473:pathology / Q000601:surgery / Q000662:veterinary*