Expression of thymidine phosphorylase and VEGF in esophageal squamous cell carcinoma

The purpose of this study was to determine the role of TP and VEGF in angiogenesis and its clinical significance in prognosis of patients with esophageal carcinoma. Expressions of TP and VEGF, microvascular density and cell proliferation activity were evaluated by using 40 immunohistochemically stained resected esophageal carcinoma tissues, and the survival rate of the patients was analyzed. Significant positive correlation and regression were found between the VEGF expression level of tumor and microvascular density (r=0.73, p<0.0001). Not statistically strong but significant positive correlation and regression were found between the TP expression level of tumor and microvascular density (r=0.32, p=0.046). No significant relationships were found between TP and VEGF expressions. Pathological T-factor and pathological N-factor were significant prognostic factors. Tumor length, site of lesion, gender, age, and Ki67 labeling index were not significant prognostic factors. The VEGF expression level was one of the unfavorable prognostic factors (risk ratio =1.035, 95% CI=1.007-1.065, p=0.01). The patients with high TP expression showed a tendency for unfavorable prognosis, but it was not statistically significant (RR=1.017, 95% CI=0.996-1.042, p=0.1). The prognosis of patients in the TP/VEGF[+/+] group was significantly poorer than that of the patients in the TP/VEGF[-/-] group and TP/VEGF[+/- or -/+] group (RR=0.488 for TP/VEGF[-/-] group, =0.717 for TP/VEGF[+/- or -/+] group, p=0.005). In conclusion, VEGF and TP expression seems to have a relationship with tumor angiogenesis, and co-expression of TP and VEGF seemed to be one of the unfavorable prognostic factors.