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Renal-cell carcinoma – novel concepts of classification

Abstract Renal cancer, according to the Polish National Cancer Registry, was the cause of 4% of cancer cases in men and 3% of cases in women in 2010. Most often it affects men over 65, although it may also concern infants. In 2010, the number of reported cases for men was 2,700 and 1,900 for women. For the last three decades – up to 1990, the incidence of kidney cancer has increased significantly. Currently, it remains at the stable level of morbidity. One of the most significant issues of modern diagnostics and treatment of renal cancer is the problem of its heterogeneity brin-ging many difficulties in systematization and categorization of this neoplasm. The World Health Organization Classification of Renal Tumors has been published in 2004 and is currently supplemented with new classification units, which, according to ISUP (International Society of Urological Pathology), should be considered as separate groups of kidney epithelial cancers.