Renal extramedullary plasmacytoma in a dog

A 10-year-old, intact male Siberian husky dog was presented for a suspected left renal cyst. Computed tomography (CT) identified a large, left kidney mass with retroperitoneal hemorrhage. A left-sided nephrectomy was performed, and histopathology confirmed a renal plasmacytoma. Perioperative screening for multiple myeloma was negative. The dog was lost to follow-up and was euthanized 11 months after surgery. A necropsy was not performed. To the authors' knowledge, this is the first case of renal extramedullary plasmacytoma in a dog. Key clinical message: This report describes the clinical presentation, and laboratory, diagnostic imaging, and surgery findings of a case of renal extramedullary plasmacytoma in a dog.