The significance of vascularisation/angiogenesis for the prognosis of colorectal cancer

Background: Angiogenesis is essential for tumor growth and metastasis and t he vascular density is known as an independent prognostic factor in several tumor entities. The aim of this paper was to examine the vascular density and to test its prognostic relevance in colorectal cancer. Methods: The population included 146 patient who were treated surgically fo r cure. Sections of these tumors were immunostained with the monoclonal ant ibody JC70, an endothelial cell marker, and with an monoclonal antibody dir ected against bFGE Microvessel quantification was assessed with a light mic roscope. All of the slides were scanned at a low magnification and individu al microvessel counts were made on a X200 field in the area of the most den se neovascularization. Results: Vascular density was 75 +/- 27/visual field which was independent of age, sex, pT and pN-category, occurrence of recurrence and overall survi val. Only recurrence-free survival was significantly shorter in tumors with higher density (> 70) than in tumors with lower density (< 70). The angiog enetic factor bFGF was only expressed in 17.1% of all patients and independ ent of tumor stage, differentiation and prognosis. Conclusions: Our results confirm that the growth of a tumor is accompanied by the onset of neovascularization. The immunostaining of tumor sections wi th JC70 is an objective and reproducible method to quantify the vascular de nsity in colorectal cancer. We could show that the quantification of angiog enesis is of little importance in clinical riskstratification for patients with colorectal cancer.