NQO1 and Balkan nephropathy: It is namely noteworthy that NQO1-polymorphism (the genotype NQO1*2/*2) seems to predispose patients suffering from BEN to the development of urothelial malignancy of the upper urinary tract (OR=13.75, 95%CI 1.17-166.21) (Toncheva et al., 2004).