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.