Conclusions: Positive preoperative voided urine cytology is an independent predictor for bladder recurrence after radical nephroureterectomy for UUT-UC.

Because of the difficulty in obtaining adequate biopsies from UUT lesions, cytologic examination is the most practical method of diagnosis.

Furthermore, our study indicates a high level of MSI in TCC-UUT, although it is a rare event in bladder cancer.

For all techniques, more research has to be conducted before these techniques can be implemented in the routine management of UUT-UC.

The convergence of molecular epidemiological and experimental data establishes a clear causal association between exposure to the human carcinogen AA and UUT.