[Interesting development of 4 cases of urothelial carcinoma of the upper urinary tract].

The authors submit a report on four patients with urothelial carcinomas of the upper urinary pathways, as in each of them the development of the disease was interesting. They draw attention to the fact that it is important to consider other possible causes of complaints of these patients, although the urologist thinks in these dispensarised patients, due to the nature of their disease, above all of the development of another urothelial tumour or spread of the original tumour.