VEGF-C and VEGF-D overexpression is more common in left-sided and well-differentiated colon adenocarcinoma

Tumour vessel network formation, including blood and lymph vessels, is a major step involved in the process of carcinogenesis. The discovery of vascular growth factors has led to a better understanding of tumour biology, thus, creating new possibilities for cancer treatment that targets angiogenesis within tumour-associated stroma, including therapy for colon cancer patients. The present study evaluated the relationships between increased expression of lymphangiogenic factors (VEGF-C and VEGF-D) and vessel density in the tumour-surrounding stroma, patient survival and other standard prognostic factors. The expression of VEGF-C and VEGF-D and vessel density were immunohistochemically assessed in 114 primary tumour specimens from colon adenocarcinoma patients after surgical resection between January 1, 2003 and December 31, 2008. Concomittant overexpression of VEGF-C and VEGF-D was found in 51 (44.7%) colon tumours and low expression was observed in 63 (55.3%) cases. Mean vessel density was 52.87/field. A significant correlation was found between the expression of factors influencing lymph vessel growth and increased vessel density in the tumour-surrounding stroma (p=0.03). A relationship between lymphangiogenic factor overexpression and left-sided tumour location was also found (p=0.00002). Overexpression of these factors was likely to occur in well-differentiated tumours (p=0.003). No association between patient survival and the expression levels of lymphangiogenic factors was observed. The study results indicate that the overexpression of lymphangiogenic factors tends to be associated with tumours of favourable prognosis, i.e. well-differentiated and those localized in the left-side of the colon.