Teaching Case

Primary tumours of the ureter are uncommon, accounting for only about 5% of all tumours of the upper urinary tract. We present a transitional cell carcinoma of the ureter diagnosed with ultrasonography.

We present a case of a 79-year-old patient, heavy smoker, with a hepatic transplant in 2000 due to cirrosis VHC positive and hepatocellular carcinoma. The patient was followed every year for a checkup and inmunosuppresive treatment with Mycophenolate Mofetil and Tacrolimus was applied correctly. Tacrolimus treatment produced a moderate renal insufficiency diagnosed in 2001. Creatinin levels did not exceed 1,6 (2009) and the mean levels since 2000 were 1,3. There was neither macroscopic nor microscopic haematuria.
During his follow-up a renal ultrasound was performed. The examination showed left hydronephrosis and dilation of the left ureter. No lithiasis was observed. Ultrasound examination of the left flank showed a thickening of the medium-distal transition of the left ureter. A soft tissue mass was observed inside the thickened ureter. A contrast enhanced CT (CECT) was performed to confirm the ureteral tumour suspicion. In the CECT a left hydronephrosis (grade IV/IV) with delayed contrast enhancement and elimination, dilation of the ipsilateral ureter and a 8mm long left ureter intraluminal soft-density lesion with slight stranding of the periureteral fat was confirmed. There was no evidence of lymphadenopathy in the abdomen.

Most tumours of the collecting system are malignant, with 91% being transitional cell carcinomas (TCC). TCC is found most frequently among patients in their 5th to 8th decades and it is rare in patients younger than 30. There is a male predominance 3-1. TCC is associated with several risk factors; the most important is smoking. Other risk factors are phenacetin abuse, caffeine abuse, Balkan nephropathy and the exposition to chemicals used in the chemical dye and plastic industries, where the prevalence of TCC is higher. TCC occurs in the urinary bladder, renal pelvis, and ureter with a relative frequency of 50 to 3 to 1. [1]
5% of urothelial tumors arise from the ureter, renal pelvis or calices, representing about 10% of upper urinary tract neoplasms. Typical presentation of patients with TCC is haematuria, which may be frank or microscopic. Almost 30% of patients complaint of flank pain or symptoms of acute renal colic. Rarely, TCC can manifest with distant metastases or be diagnosed incidentally at a radiologic examination. Just about 25% of the upper urinary tract tumours occur in the ureter, where 60%–75% of cases are found in the lower third. TCC spread can occur by mucosal extension or local, haematogenous or lymphatic invasion. The most frequent sites of metastases are the liver, bone, and lungs. [2]
Infiltrating tumours usually produce thickening and induration of the ureteral or renal pelvic wall. When the renal pelvis is involved, there is usually invasion in the renal parenchyma. However, renal cell carcinomas are typically expansive and have a infiltrative growth pattern that preserves the renal contour.
The diagnosis of upper tract TCC is usually made with excretory urography in patients undergoing investigation for haematuria. Excretory urography is the imaging study of choice for the pelvicaliceal system and ureters although CT urography is becoming more accurate and accepted as a primary diagnostic investigation. CT has been shown to be more sensitive than either ultrasound or excretory urography in the detection of small renal mass lesions and urinary tract calculi.
In the ultrasonography, a renal pelvic TCC is observed as a central soft-tissue mass in the renal sinus with or without hydronephrosis. Ultrasonographycal evaluation of ureteral TCC is not easy; the ureters are rarely visualized in their entirety, even if they are dilated. If they are visualized, intraluminal soft-tissue mass with proximal distention of the ureter is typically observed.
CT is the best technique for preoperative staging of the upper tract TCC. The CT offers a single breathhold coverage of the kidney and urinary tract with a good soft tissue resolution that can demonstrate the longitudinal extent of the lesion and permits assessment for multicentric tumours. When diagnosed with CT a TCC can be seen like an eccentric or circumferential thickening of the ureteral wall or as a intraluminal soft tissue mass. [3]