Biology of renal cell carcinoma: changing concepts in classification and staging.

Advances in our understanding of the pathogenesis, behavior, and importance of prognostic factors for renal cell carcinoma (RCC) have paved the way for increased sophistication in its classification and staging. In the past, lack of consistent classification and terminology for RCC histology and staging has complicated comparability of clinical studies looking at patient prognosis and response to treatment. In this review, the results of international consensus efforts to achieve uniform classification systems for RCC are outlined and some future directions are considered.