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. Fifty patients operated on for CRCC by radical nephrectomy were included. Clinical and histologic parameters were studied. VEGF expression and VEGF pattern in tumor cells was immunohistochernically recorded. pVEGF levels and platelet count were analyzed in relation to clinical and histologic parameters. Intraturnoral VEGF expression associated with a cytoplasmic VEGF pattern was significantly higher in patients with high pVEGF levels (P =.01). Both VEGF expression and pVEGF levels were significantly correlated with Fuhrman grade (P =.002 and P =.01, respectively) and tumor stage (P =.006 and P.008, respectively). In addition, VEGF expression was also correlated with tumor necrosis (P =.001) and progression (P=.001). We demonstrated thatin CRCC with tumornecrosis, VEGFexpression, pVEGF levels, and platelet count were significantly higherthan in CRCC with no turriornecrosis (P=.001, P.03, and P =.001, respectively). Our results revealed that cytoplasmic VEGF expression and pVEGF levels are associated with usual prognostic factors and progression in CRCC, which may allow VEGF to be used as a prognostic marker for CRCC, especially in patients with VEGF-targeted therapy. (c) 2007 Elsevier Inc. All rights reserved.