RESUMO
Papillary transitional cell tumors of the renal pelvis and ureters occur more frequently in the Balkan countries than in other areas in the world. The populations involved are the same as those who are at risk to develop Balkan endemic nephropathy (BEN). Seventy-seven patients were treated in the Urology Clinic for papillary cell tumors of the renal pelvis and ureters (UTT) from 1986 to 1988. Forty-four of the patients were from areas where BEN is endemic. The at-risk population is estimated to be less than 2% of the control population. Eleven of the 77 were on hemodialysis when UTT were detected, and all but one of those were from BEN areas. This finding emphasizes the need for continual monitoring of end-stage renal disease patients for evidence of these tumors. Comparing the frequency of the tumors from our study (1986 to 1988) with that of early studies indicates that the risk of developing the tumors remains very high in the BEN areas. We conclude that the causative agent(s) is still prevalent in the involved areas.