FDG PET/CT in a Case of Primary Lymphoma of the Ureter.

Primary lymphoma of the ureter is extremely rare. We describe the contrast-enhanced CT and FDG PET/CT findings in a case of diffuse large B-cell lymphoma transformed from mucosa-associated lymphoid tissue lymphoma limited to the left ureter. Contrast-enhanced CT showed 2 short-segment circumferential thickening and enhancement of the left pelvic and intramural ureteral wall. The thickened ureteral wall showed significantly increased FDG uptake mimicking urothelial carcinoma.