Current insights in renal cell cancer pathology

In recent years molecular biologists and pathologists have described new entities of renal cell cancer (RCC) with a totally different morphology and biology among the histotypes of renal carcinoma, but always referring to the same renal cancer disease. The evidence of a distinct biological behavior and long-term prognosis among these makes the correct pathological diagnosis of renal cancer critically important for the clinician. Advances in understanding of the pathogenesis, behavior, and importance of prognostic factors for RCC have paved the way for a revision of its classification and staging. We reviewed the role of histological classification, microscopic tumor necrosis, microscopic venous invasion, lymph node involvement and, particularly, pathological stage. In our series of patients who underwent renal surgery for neoplasm, a retrospective study established the predictive role of tumor size on recurrence rate, compared with other known prognostic factors, and we conclude that histological grade, pathological stage and tumor size remain relevant prognosticators in early stage RCC patients. In order to optimize the management of patients with RCC it is necessary to develop an interdisciplinary approach (surgeon, radiologist, pathologist, oncologist) and find new prognostic parameters at molecular and cellular levels. Many efforts are ongoing to integrate molecular data (from tissue microarrays) and clinical data (traditional prognosticators) into a molecular integrated staging system. In the postgenomic era, new tumor-associated antigens and molecules can be identified at the protein level using proteomics, providing a major opportunity for screening and finding novel targets that are the basis of new emerging therapies for RCC.