Balkan endemic nephropathy (BEN) is a chronic tubulointerstitial disease prevalent in Croatia, Romania, Bulgaria, Bosnia and Herzegovina, and Serbia. In addition to renal disease, an increased incidence of upper urothelial carcinomas (UUCs) has been observed in the foci of BEN. Carcinoma may occur alone or in combination with BEN. Immunosuppression is associated with an increased risk for development of different malignancies. There are no data in the literature about the outcome of patients with BEN after transplantation.We performed a retrospective evaluation of the database and review of the charts and pathology reports of 601 renal transplant recipients treated at our institution.From January 1995 to December 2004, kidney transplantations were performed in nine patients with BEN. One-year graft survival was 100%. A man, who was transplanted in 1997 died 2 years after transplantation with a functioning graft due to disseminated cancer from the pelvis of his own kidney. A female patient developed UCC 2 years after transplantation. They were both treated with a bolus of methylprednisolone before transplantation, because of four HLA-mismatches. A male patient developed UCC in the native and transplanted kidneys. He underwent a native nephroureterectomy with partial nephroureterectomy of transplanted kidney. His graft function was preserved with decreased immunosuppression. Three years later a urinary bladder carcinoma was discovered on a regularly performed multislice computed tomography. One patient developed a skin malignancy. Other patients have had uneventful posttransplantation courses with excellent graft function. Thus, 33.3% of patients with BEN developed UUC, compared with a 0.67% prevalence of urinary tract tumors among transplanted patients with other causes of end-stage renal disease.Patients with BEN are at increased risk for the development of UCC after transplantation. Regular screening for early detection of malignancy is mandatory. Longer follow-up and results from other transplant centers are needed to further investigate the relationship between BEN and UCC after renal transplantation.