[Balkan nephropathy and urothelial cancer].

In Bulgaria, the frequency of tumors of the renal pelvis and of the ureter is very high in the regions affected by Balkan nephritis. An increased frequency of these tumors is also reported in Yugoslavia, though to a lesser extent; however, these urothelial tumors are frequent in the endemic regions affected by Balkan nephritis, but a less significant frequency of cases is also noted in neighboring, non-endemic regions. The geographic distribution of these diseases of the urinary tract is studied, as well as the related issues of urothelial carcinogenesis.