Parenchymal Renal Carcinoma: The Role of the Pathologist

Renal Cell Carcinoma (RCC) comprises 85% of all primary renal neoplasms. They are frequently diagnosed in an advanced stage and approximately 25% of patients present with metastases at the time of first diagnosis. In RCC pathologists are faced not only with morphologic problems, but also with evaluating parameters that could be utilised in monitoring the clinical course and in prognosis. At present staging, nuclear grading and study of DNA content provide information of prognostic value. However other biological markers are under study: AgNOR, growth fraction, oncogene and tumor-suppressor gene expression and adhesion molecules could provide new valuable information with therapeutic and prognostic implications. There is also a need for the development of sensitive molecular markers for the early detection of RCC: recently nephrocalcin and a guanidinbenzoatase have been proposed as such. The advances in molecular biology and in cytogenetics have shed some light on the pathogenesis of RCC. Alterations in tumor-suppressor genes on chromosome 3 and on chromosome 17 have been frequently observed in most RCC.