Abstract

Angiogenesis is essential for the growth of solid tumors. Microvessel counts, which represent a measure of tumor angiogenesis, have been correlated with the overall survival of patients with a variety of malignancies. However, the significance of angiogenesis in renal cell carcinoma remains controversial. To determine whether angiogenesis correlates with prognosis of patients with renal cell carcinoma, we counted the microvessels within the primary tumors and compared their numbers with patients' prognosis. Tumor specimens from 42 patients were investigated. Microvessels were stained with anti-CD34 and anti-factor VIII-related antigen monoclonal antibodies. Significant correlation between microvessel counts for two antibodies was observed (r=0.875, p<0.01), although microvessel counts for CD34 were approximately two times higher. Microvessel counts were higher in clear cell than in non-clear cell carcinoma (p<0.05). These results suggest that immunostaining with anti-CD34 antibody may provide a more sensitive and accurate measure of tumor angiogenesis. There was no correlation between microvessel counts and nuclear grade, or TNM stage. In univariate analyses, nuclear grade and TNM stage were significantly associated with patient survival (p<0.01). But further studies on tumor angiogenesis of renal cell carcinoma are needed before it can be adopted as a prognostic marker.

• Keywords: Angiogenesis;Renal cell carcinoma;CD34;Factor VIII-related antigen