Imaging Features Of Unilateral Renal T-Cell Lymphoma Occurring Simultaneously In The Urinary Bladder Wall And Contralateral Ureter With Secondary Polycythaemia In A Dog

A six-years-old neutered male Labrador Retriever was presented with haematuria and inappetence of one-week duration. Physical examination revealed mild abdominal pain and the blood cell count showed moderate polycythaemia, with a slight increase of the erythropoietin levels. Urinalysis demonstrated proteinuria, haematuria and isosthenuria and urinary sediment revealed mild amount of lymphoid cells. After performing a complete imaging study (radiographs, ultrasound and CT scan), a unilateral renal lymphoma with secondary extranodal lymphoma of the urinary tract (bladder wall and left ureter) was suspected. Fine-needle aspirates of both kidneys, ureter and bladder masses were obtained, and a tentative diagnosis of lymphoma was made. Positive PCR antigen receptor rearrangement indicated a T-cell origin. The owners opted for euthanasia and declined necropsy. CT was essential for the evaluation of this case, not only depicted renal lesions, but also identified accurately extension to adjacent anatomic structures helping to determine the systemic spread of the disease.