Microvessel density and expression of vascular endothelial growth factor in clinically localized prostate cancer

Identifying biological differences between benign lesions and malignant prostatic cancer (PC) may facilitate precise indication for more aggressive post-operative treatment. Therefore, we examined immunohistochemically histological specimens from 140 PC patients treated with radical surgery. The mean age of the patients was 62.9 ±6.2 (range 49.0-77.0) years. There were 13 (9.3%) at pTNM stage 1, 78 (55.7%) at stage 2, 40 (28.6%) at stage 3 and 9 (6.4%) at stage 4. In the analysed group there were 75 (53.6%) well-differentiated, 53 (37.8 %) moderately differentiated and 12 (8.6%) poorly differentiated tumours.

The mean pre-operative prostate-specific antigen (PSA) level was 9.9 ±0.5 ng/ml. Concentration of serum PSA was significantly increased with pTNM stage (p = 0.011), Gleason score (p = 0.011) and tumour grade (p = 0.003). In 34 (24.3%) tumours vascular endothelial growth factor (VEGF) expression was not shown. In the analysed group of tumours the mean percentage of positive VEGF cells was 14.8 ±1.4% and was not correlated with tumour grade (p = 0.648) or Gleason score (p = 0.697). However, significantly higher values for the protein were observed in pTNM 3 (p = 0.035) and pTNM 4 (P = 0.037) than in pTNM stage 1. In the whole series of tumours the mean microvessel density (MVD) was 97.5 ±2.4 /mm². A non-significant decrease in the number of microvessels was observed in the highest pathological tumour volume (P = 0.631), Gleason score (p = 0.368) and tumour grade (p = 0.233). Prostate-specific antigen level was not associated statistically with either MVD (p = 0.466) or VEGF expression (p = 0.188). There was also no correlation between the immunohistochemical expression of VEGF and MVD (p = 0.925).