Primary Ureteral Lymphoma Presenting with Acute Flank Pain

Ultrasonographic diagnosis of a lymphomatous lymph node presumptively infiltrating the ureter causing hydronephrosis in a 3-year-old dog

A 3-year-old male neutered mixed breed dog was presented for chronic vomiting and diarrhea. Abdominal ultrasound revealed a large amorphous, heterogeneous mass within the left mid to caudal abdomen most consistent with medial iliac lymph node. It appeared to invade the left ureter and extend distally causing ureteral obstruction and hydronephrosis. Concurrent additional ultrasound findings were consistent with metastatic or multicentric neoplasia. Fine needle aspirates of the lymph node and spleen both confirmed large cell lymphoma. These findings present evidence of lymphoma invading directly from an organ into the ureter which has not previously been reported in dogs.

Ureteric lymphoma as a rare cause of right lower ureteric obstruction

Primary lymphoid neoplasms of the urinary tract are exceedingly rare, with only 21 cases being reported and comprising less than 5% of all primary extranodal lymphomas. We report a case of a 45-year-old man who presented with right flank pain and weight loss, and who was found to have a stricture in the right lower ureter causing ureteral obstruction. Histopathology revealed lower ureteric non-Hodgkin lymphoma, which, on further evaluation, was found to be isolated ureteric lymphoma. The patient was doing well after six cycles of R-CHOP chemotherapy. This case is being reported as a rare cause of distal ureteric obstruction.