High Level Expression of Platelet-derived Endothelial Cell Growth Factor predicts Good Prognosis in Colorectal Cancer Patients

Platelet-derived endothelial cell growth factor (PD-ECGF) is one of the angiogenic factors. PD-ECGF expression is elevated in colorectal carcinoma, but its prognostic value does not reach a consensus. The aim of this study is to clarify the prognostic value of the PD-ECGF expression in colorectal carcinomas. PD-ECGF expression was measured by enzyme- linked immunosorbent assay in frozen materials from 71 colorectal cancer patients who had recived curative resection. Patients were divided into high expression and low expression groups based on cut-off value. Correlations among PD-ECGF expression, clinicopathologic features, and disease-free interval were studied by univariate and multivariate analysis. To evaluate the origin of PD-ECGF, serial sections of 71 tumors were stained for PD-ECGF and CD68. PD-ECGF expression in normal mucosa was 34.4 ﾂｱ 15.5 (Units/mg protein) and the cut-off value was 65.4 (mean+2SD). There were no significant correlations between clinicopathological features and PD-ECGF expression. The disease-free interval for high PD-ECGF expression group was significantly longer than that of low expression group (P=0.006). A multivariate Cox\u27s regression analysis revealed a high PD-ECGF expression as an independent factor for better outcome. In immunohistochemical study, almost all tumor cells were negative for PD-ECGF, but stromal macrophages were predominantly positive for PD-ECGF. In conclusion, the PD-ECGF expression measured in this study was derived from stromal macrophages. High PD-ECGF expression was a predictor for favorable outcome after curative resection for colorectal cancer