[Correlation of microvascular density and clinicopathological factors in different subtypes of renal cell carcinoma]

The aim of this study was to evaluate the expressions of CD34, CD31 and microvessel density (MVD) in different subtypes of renal cell carcinoma (RCC) as well as the relationship between MVD and clinicopathological factors.

Expressions of CD31 and CD34 were detected in 149 patients with RCC using SP immunohistochemical staining. The MVD was studied by Weidner's method.

The expressions of CD31 and CD34 in the clear cell renal cell carcinoma (CCRCC) (98.35 +/- 55.05, 128.04 +/- 46.44) were significantly higher than those in chromophobe renal cell carcinoma (ChRCC) (30.70 +/- 17.72, 48.55 +/- 14.09) and papillary renal cell carcinoma (PRCC) (21.60 +/- 9.38, 38.12 +/- 10.98) (P < 0.01). The MVD value marked by CD31 (30.70 +/- 17.72, 21.60 +/- 9.38) was much lower than that marked by CD34 (48.55 +/- 14.09, 38.12 +/- 10.98) between ChRCC and PRCC (P < 0.01). Smaller and immatured microvessels and even single endothelial cells could be clearly seen. The MVD values marked by CD31 and CD34 were negatively correlated with the pathological grades (r(CD34) = -0.618, P < 0.01; r(CD31) = -0.442, P < 0.01) and clinical stages (r(CD34) = -0.283, P < 0.05; r(CD31) = -0.256, P < 0.05) in CCRCC. But no association was found in non-CCRCC (P > 0.05).

MVD is significantly correlated with different types of endothelial labeling. The microvascular endothelial cells could be shown clearly by its related antigen labeling such as CD34 and CD31. CD34 is more sensitive than CD31. The MVD of CCRCC is significantly higher than that in non-CCRCC. The expressions of CD31 and CD34 are not correlated with tumor grade and stage in ChRCC and PRCC, while there is a negative correlation in CCRCC.