Stage I colorectal carcinoma: VEGF immunohistochemical expression, microvessel density, and their correlation with clinical outcome

Tumor-node-metastasis (TNM) stage I colorectal cancer is commonly characterized by a good prognosis, with 5-year survival around 80-90%; nonetheless, it undergoes disease progression in a percentage of cases, although the causes of adverse clinical course still remain to be elucidated. In the present study, we analyzed and compared the immunohistochemical expression of the pro-angiogenic vascular endothelial growth factor (VEGF) as well as the microvessel density (MVD) in a series of 27 surgically resected colorectal carcinomas obtained from patients deceased because of disease progression and in a cohort of 25 colorectal cancers from patients still alive with no evidence of disease progression 5 years after the initial diagnosis. The prognostic value of VEGF expression and of MVD on the overall survival to colorectal cancer was investigated. A variable VEGF immunoexpression was demonstrated in all the analyzed cases. High VEGF expression was significantly more frequent among patients deceased of the disease. These patients also displayed significantly higher MVD counts in their cancer in comparison to the patients alive after 5 years from surgery. Moreover, both high VEGF expression and MVD appeared as significant negative prognostic markers related to a shorter overall survival to stage I colorectal carcinoma, with VEGF representing an independent variable at multivariate analysis. VEGF assessment might be used in order to select those patients with a higher progression risk and to submit them to adjuvant therapies useful to prevent adverse outcome.