Renal Pelvic and Ureteral Tumors
As in the bladder, the preponderance of renal pelvic and ureteral tumors are urothelial transitional cell carcinomas (TCCs). Incidence is considerably lower than in the bladder--such tumors represent only about 4% of all urothelial tumors. However, there is an unexplained predisposition for inhabitants of the Balkans to develop upper urinary tract TCC (Balkan nephropathy); in that population, half of all renal pelvic tumors are TCC. The incidence of concurrent bilateral TCC tumors is 10 times higher than in inhabitants of other geographic areas. The biology of these tumors, including their metastatic behavior, is similar to that of TCC of the bladder.
Symptoms, Signs, and Diagnosis
Hematuria is the most common presenting symptom of renal pelvic and ureteral tumors. Retrograde urography performed in conjunction with cystoscopy remains the most definitive imaging study for characterizing these lesions.
Ureteral tumors uncommonly cause renal colic symptoms (unless a blood clot functions as an intermittently obstructive foreign body); however, retrograde urography commonly shows ureteral tumors as obstructive lesions with varying degrees of hydronephrosis above.
Renal pelvic tumors less commonly cause hydronephrosis (unless the tumor obstructs the ureteropelvic junction). On intravenous urography, a filling defect in the renal collecting system is seen. On CT, the major differential diagnosis is between TCC of the renal pelvis and adenocarcinoma of the renal parenchyma.
Although x-ray imaging of these lesions is critical for initial diagnosis (in contrast with diagnosis of bladder cancer), cytologic or histologic confirmation of the diagnosis is imperative before treatment. Endoscopic catheterization of the ureter for cytologic collections, usually after fluoroscopically controlled endoscopic brushing of the lesion, is usually performed with anesthesia. Miniaturized ureteroscopes permit direct visualization and biopsy of these lesions.
Treatment
Renal pelvic lesions are treated surgically with total nephroureterectomy. Radiation therapy has no role because of the poor tolerance of renal parenchyma to external beam radiation therapy. However, newer techniques permit renal preservation. Low-grade ureteral lesions (and also renal pelvic lesions clearly not contiguous with renal parenchyma) can be fulgurated with laser energy transmitted by fiber through a ureteroscope. Distal high-grade lesions can be managed by partial ureterectomy with reconstruction (including bowel interposition), unless multifocal carcinoma in situ demands total nephroureterectomy. Although the biologic risk and rationale for adjuvant chemotherapy for high-grade invasive disease of the renal pelvis and ureter is similar to that of the bladder, the rarity of this disease has precluded a full evaluation of its clinical effect. Management of metastasis is essentially identical to that of bladder cancer.
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