High incidence of papillary renal cell tumours in patients on chronic haemodialysis.

Papillary and nonpapillary renal cell tumours can be differentiated according to their genetic constitution. In this study, their incidence in end stage kidney disease has been investigated histologically. Nonpapillary renal cell carcinoma was observed in 22 cases (51.2%) whereas papillary renal cell tumours were diagnosed in 21 (48.8%) of the 43 patients with end stage kidney disease. The incidence of papillary renal cell tumours in end stage kidney disease is significantly higher (chi 2 = 31.9; P < 0.001) than in the general population (4.8%). Haemodialysis patients with nonpapillary and papillary renal cell tumours did not show significant differences in age, sex or size of tumour. However, patients with papillary renal cell tumours had received longer duration of haemodialysis than patients with nonpapillary renal cell carcinomas. These data suggest that not only different genetic events but also different aetiological factors are involved in the development of the two types of tumour in end stage kidney disease.