Microvessel density in prostate carcinoma

Abstract

The objective of this work was to assess the correlation between microvessel density (MVD), pathological stage and disease recurrence in a series of patients who underwent radical prostatectomy for prostate cancer. Pathological material from 75 consecutive radical prostatectomies performed before 1994 without neoadjuvant treatment, in which sufficient follow-up data were available, was reexamined. Paraffin embedded material was re-cut and hematoxylin and eosin (H&E) stained. Areas of maximal angiogenesis within tumor were identified. Expression of CD34 was investigated by using the monoclonal antibody MY 10. Within the areas of maximal angiogenesis, microvessels expressing CD34 were counted and specimens were divided into two groups, one showing a count of less than 90 microvessels per microscopic field at 2006magnification (MVD < 90), the second more than 90 microvessels (MVD > 90). The MVD was then related to pathological stage, Gleason score (GS) and outcome of the disease. Mean followup was 84 months. Clinical or biochemical progression was observed in 38.6% of patients. In low GS cases, MVD was always < 90, whereas in GS 5 -6, half had MVD < 90 and half were > 90. In high GS MVD was always > 90. MVD was positively associated with a higher pathological stage. Progression of the disease was observed in 20% of MVD < 90 and in 51% in MVD > 90 (P ¼ 0.006). MantelHaensz test showed a correlation between MVD and time to progression (P < 0.05). Although problems exist in methods of counting and in the cut-off number of vessels, which can discriminate the risk categories, it may be concluded that microvessel counts, using CD34 monoclonal antibody, can accurately predict the outcome of radical prostatectomy.

Impaired access of lymphocytes to neoplastic prostate tissue is associated with neoangiogenesis in the tumour site

“…To address this issue, we related numbers of newly formed vessels in foci of carcinoma and benign tissue to patterns and extent of leukcocyte infiltrates assessed according to common and subset-specific markers. In concordance with previous reports (Bono et al, 2002;Strohmeyer et al, 2004), we detected increased numbers of microvessels in the vicinity of malignant glands (Figure 1). Tissue-infiltrating leukcocytes were found in both adenocarcinoma and NHPG specimens; however, the malignant and benign prostate tissues markedly differed in pattern of infiltration (Figure 2).…”

“…Neoangiogenesis is an integral part of tumour progression, where a vasculature in primary neoplastic lesion undergoes 'angiogenic switch' and converts into a chaotic network of rapidly proliferating blood vessels displaying marked structural and molecular abnormalities (Bono et al, 2002;Ryschich et al, 2002;Strohmeyer et al, 2004;Ozawa et al, 2005). Studies employing experimental murine tumour microcirculation models and intravital fluorescent microscopy techniques demonstrated impaired interactions between circulating leucocytes and endothelial cells, thus implying the existence of a barrier function in tumour-associated blood vessels (Ryschich et al, 2002;Dirkx et al, 2003;Garbi et al, 2004).…”

“…In course of this disease, the numbers of newly formed microvessels progressively increase (Montironi et al, 1993;Mazzucchelli et al, 2000;Bono et al, 2002;Strohmeyer et al, 2004;Ozawa et al, 2005). However, it is not known whether these neovessels may attenuate migration of lymphocytes to malignant lesions and if so, whether vascular CAMs are involved.…”

Effects of androgen suppression and radiation on prostate cancer suggest a role for angiogenesis blockade

“…17,22 Increases in VEGF, as well as in other angiogenic factors, have been shown to correlate with a worse prognosis in multiple solid tumours and direct measurement of angiogenesis via microvessel density (MVD) assays has also correlated negatively with prognosis in multiple cancers, including prostate. [23][24][25][26][27] VEGF expression and intratumoural MVD both correlate with decreased survival in men with prostate cancer, and MVD correlates with disease progression after radical prostatectomy. [26][27][28] There is evidence that plasma levels of VEGF are increased in patients with metastatic prostate cancer 29,30 and that anti-VEGF antibodies can prevent the growth of in vivo prostatic tumour models beyond the initial prevascular growth phase.…”

“…[23][24][25][26][27] VEGF expression and intratumoural MVD both correlate with decreased survival in men with prostate cancer, and MVD correlates with disease progression after radical prostatectomy. [26][27][28] There is evidence that plasma levels of VEGF are increased in patients with metastatic prostate cancer 29,30 and that anti-VEGF antibodies can prevent the growth of in vivo prostatic tumour models beyond the initial prevascular growth phase. 31,32 The effects of hormones and hypoxia on angiogenesis Data addressing the stimulatory effect of androgens on angiogenesis suggest a possible role for androgens themselves as angiogenic survival factors in prostate cancer.…”