A kidney cancer is based on malignant changes in kidney cells. If the cancer develops from different cells of the kidney tissue, this is called renal cell carcinoma. Renal cell carcinoma is the most common type of kidney tumor in adults, accounting for more than 80 percent of cases. Generally speaking, however, renal cell carcinomas are quite rare, accounting for only about three percent of all cancer cases.
The remaining types of kidney cancer develop from the urinary tract or from lymphatic tissue. It is also possible that kidney tumours are metastases (daughter tumours) of other cancers in the body.
In Germany, there are more than 6,500 new cases in women and more than 10,000 new cases in men every year. The incidence of the disease increases sharply with age - the average age of onset is 67 for men and 71 for women.