Ultrasonographic findings of multicentric malignant lymphoma involving the urinary bladder in a dog: Diagnosis and monitoring during chemotherapy.

A 5.5-year-old spayed female cane corso dog was presented for recurrent hematuria and dysuria. Abdominal ultrasound demonstrated severe hypoechoic urinary bladder wall thickening with irregular mucosal surface and polypoid-like lesions protruding into the lumen, abdominal polyadenomegaly, and splenic honeycombing. High-grade lymphoma was diagnosed on urinary bladder wall cytology. Clinical signs and ultrasonographic findings initially improved following a modified CHOP-based chemotherapy protocol, but the multicentric lymphoma then progressed with thoracic spread, leading to the dog's death at 9 wk post-diagnosis. Key clinical message: This case report describes the ultrasonographic features of malignant lymphomatous infiltration of the urinary bladder and emphasizes the importance of including lymphoma in the differential diagnosis for parietal urinary bladder lesions. It also describes the endoscopic findings of such an infiltration that have not yet, to the authors' knowledge, been described or illustrated in the veterinary literature. Finally, this case report underlines the poor prognosis of multicentric lymphoma involving the urinary bladder, with rapid progression of the disease and short survival time despite chemotherapy.