Paraffin-embedded tissue is less accurate than frozen section analysis for determining VHL mutational status in sporadic renal cell carcinoma.

Introduction: Literature controversies exist regarding the prognostic value of VHL mutations. The objective was to compare paraffin-embedded and frozen section specimens for VHL mutations detection and to evaluate the reliability of DNA analysis in formalin-fixed tissues.

Methods: Seventy-six patients with clear cell renal cell carcinoma (RCC) previously assessed for VHL status from frozen samples were included.

Plasma level and tissue expression of vascular endothelial growth factor in renal cell carcinoma: a prospective study of 50 cases.

Vascular endothelial growth factor (VEGF) is the major factor involved in angiogenesis. Although it is known that one of the functions of VEGF is to regulate neovascularization in renal cell carcinomas, the relationship between the production of VEGF in tumor tissue and its concentration in blood has not yet been studied. The aims of this study were to determine, in a series of conventional renal cell carcinoma (CRCC) cases, (1) VEGF expression and VEGF pattern in tumor cells, (2) the relationship between VEGF expression/pattern and VEGF levels in plasma (pVEGF), and (3) the association with usual clinical and pathologic prognostic factors.