Expression of Vascular Endothelial Growth Factor in Cancer Tissues and Serum of Gastric Cancer Patients: Correlation with Clinicopathologic Findings and Prognosis

ABSTRACT

PURPOSE: Vascular endothelial growth factor (VEGF) is known to be produced by various malignant tumors and thought to be involved in microvascular permeability and angiogenesis. However, the clinicopathologic significance of the expression of VEGF in gastric cancer remains unclear. METHODS: To examine the relationship between VEGF expression in gastric cancer and clinicopathologic factors or patient survival, tumor VEGF expression was assessed by immunohistochemical study in 144 gastric cancer patients. In addition, serum VEGF (S-VEGF) level was measured by enzyme-linked immunosorbent assay in 116 patients and in 32 healthy controls. RESULTS: Positive staining for VEGF was observed in 68.8% (99 out of 144) of gastric cancers, and its expression was observed more frequently in patients with intestinal type and serosal invasion tumors. However, there was no significant correlation between the patients' survival and VEGF positivity. Significant differences in preoperative S-VEGF level were found between healthy controls and patients with gastric cancer (P=0.014), whereas there was no significant difference in the S-VEGF level between control and curative resection group. When S-VEGF levels were compared between groups categorized by different clinicopathologic vari-ables, a significant correlation was found between a high S-VEGF level and a tumor size greater than 5 cm, serosal invasion, lymph node and distant metastasis. Moreover, postoperative S-VEGF levels were significantly elevated as compared to preoperative levels (P=0.000). When the median S-VEGF level was used as a cutoff level, the survival rate of patients with elevated S-VEGF levels was significantly lower than that of patients with low levels (P=0.001). CONCLUSION: These results demonstrate that a high preoperative S-VEGF level is associated with tumor progression, metastasis and a poor outcome in patients with gastric cancer. Further studies are warranted to determine the clinical value of S-VEGF as an tumor marker and an indicator of tumor angiogenesis in gastric cancer.