Clinical characteristics and outcome of dogs with presumed primary renal lymphoma

OBJECTIVES: To characterise the presentation, clinicopathologic data and outcome of 29 dogs with presumed primary renal lymphoma. MATERIALS AND METHODS: Retrospective analysis of medical records of dogs with suspected primary renal lymphoma from 11 institutions. RESULTS: All dogs were substage b, and lethargy and gastrointestinal signs were common presenting complaints, as were azotaemia (n=25; 86%) and erythrocytosis (n=15; 51%) on biochemical testing. Ultrasonography typically revealed bilateral renal lesions (n=23; 79%), renomegaly (n=22; 76%) and abdominal lymphadenopathy (n=14; 48%). Chemotherapy was the only treatment in 23 dogs, of which 11 responded, all considered partial responses. For all dogs the median progression-free survival and median overall survival times were 10 days (range: 1 to 126) and 12 days (range: 1 to 212), respectively, and for dogs that responded to chemotherapy 41 days (range: 10 to 126) and 47 days (range: 10 to 212), respectively. CLINICAL SIGNIFICANCE: Primary renal lymphoma in dogs appears to be associated with a poor prognosis and short-lived response to chemotherapy.