Kidney tumours form a broad spectrum of distinguished histopathological and molecular genetic entities. The last WHO classification is dated to 2004.
Current classification has been published in October 2013 by ISUP (International Society of Urological Pathology). There were 5 new epithelials tumours: tubulocystic renal cell carcinoma (RCC), acquired cystic disease-associated RCC, clear cell (tubulo-)papillary RCC, the MiT family translocation RCCs (in particular t(6;11) RCC), and hereditary leiomyomatosis RCC syndrome-associated RCC.
Another 3 subtypes of RCC were added as "provisional" entities: thyroid-like follicular RCC; succinate dehydrogenase B deficiency-associated RCC; and ALK translocation RCC. Modifications were performed in already existing entities: multicystic clear cell RCC (formerly multilocular cystic RCC) is newly included as a subcategory of clear cell RCC with low malignant potential.
Oncocytic papillary RCC (PRCC) has not been recognized as a distinctive subcategory of PRCC yet. Hybrid oncocytic-chromophobe tumour was placed within the chromophobe RCC category.
Recent advances related to collecting duct carcinoma, renal medullary carcinoma, and mucinous spindle cell and tubular RCC were elucidated. Outside of the epithelial category, current approach to our understanding of angiomyolipoma, including the epithelioid variant and angiomyolipoma with epithelial cysts was clarified.
Cystic nephroma and mixed epithelial and stromal tumour were considered as a spectrum of one entity. Synovial sarcoma was placed within the sarcoma group.
The new classification is to be referred to as the International Society of Urological Pathology Vancouver Classification of Renal Neoplasia.