Elevated tumour markers in patients with Balkan endemic nephropathy

Balkan nephropathy (BEN) is commonly associated with urothelial cancer. Urothelial cancer is manifested in the advanced stage of disease. The aim of this study was to facilitate early detection of urothelial cancer in BEN patients and their family members living in an endemic region by using tumour markers, carcinoembryonic antigen (CEA) and tissue polypeptide antigen (TPA), and a putative marker, ferritin. Fifteen BEN patients with normal renal function, 17 with renal failure (BEN-RF), 13 healthy members of their families (HFM), 14 patients with glomerulonephritis (GN) and 12 healthy controls (C) were studied. Serum CEA levels in BEN patients were within normal limits, however, in BEN-RF patients they were significantly increased over HFM (p<0.05). Serum TPA levels in BEN and BEN-RF patients were significantly higher than in the C and HFM groups (p<0.05). Urinary CEA was not significantly different between the groups studied. Urinary TPA levels in HFM (median 125 U/l, BEN (236 U/l) and BEN-RF (275 U/l) were significantly increased over C (30 U/l), however, TPA levels were increased also in GN patients (437 U/l). None of the BEN patients studied developed urothelial cancer during the ten years' follow-up. Markedly elevated urinary TPA-like levels in all patients studied (HFM, BEN, BEN-RF, GN) suggest that urinary TPA may not be a reliable tumour marker. However, the clinical relevance of high TPA levels in BEN patients should be evaluated.