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Transitional cell carcinoma of the upper urinary tract after cystectomy.

OBJECTIVE
To assess the incidence, characteristics and outcome of upper urinary tract tumors (UUTTs) that developed in patients who underwent radical cystectomy for urothelial carcinoma.


METHODS
We performed an analysis of original and review articles that were related to post-cystectomy UUTTs. The articles were published from 1984 through 2011 and were identified by searching the Pub Med database.


RESULTS
The incidence of post-cystectomy UUTT ranges from 2-6% and is stable over time. The primary risk factors include a tumor in the distal ureter in the cystectomy specimen and signs of multifocal disease (e.g., multiplicity, a history of non-muscle-invasive bladder tumor, diffuse carcinoma in situ and the presence of a tumor in the prostatic urethra). The median time between cystectomy and UUTT exceeded three years in 70% of the reviewed cases. Even with regular radiological follow-up visits, over 50% of cases were diagnosed after clinical onset, and over 70% were in an advanced stage. Currently, a multidetector computed tomography urography is the standard technique for studying the upper urinary tract. In patients with urinary diversion, the maximum yield of cytology can be obtained when this technique is used to confirm a clinical or radiological suspicion of UUTT. Nephroureterectomy is the treatment of choice for these tumors. The high prevalence of high-grade and stage UUTT results in endourological treatment being restricted to only selected cases. Despite surgery, fewer than 30% of post-cystectomy UUTT patients experience prolonged survival.


CONCLUSIONS
Post-cystectomy UUTT is rare and usually has a late onset. A distal ureteral tumor and the presence of multifocal disease are its primary risk factors. Most cases of post-cystectomy UUTT are diagnosed clinically and in advanced stages.