Uroabdomen following rupture of a primary ureteral soft tissue sarcoma in a Labrador retriever

A seven-year-old, female neutered Labrador retriever presented for acute onset of lethargy and abdominal pain. Imaging showed the presence of an irregular mass in the left retroperitoneal space, extending from the caudal pole of the left kidney to the urinary bladder, and a moderate amount of peritoneal effusion. The excretory urography confirmed that the mass was originating from the ureter and the effusion was consistent with urine leakage. A left ureteronephrectomy was performed and histology revealed a primary soft tissue sarcoma of intermediate grade. This is the second description of ureteral soft tissue sarcoma and report of uroabdomen due to ureteral mass in veterinary literature.