Serum VEGF during chemo-radiotherapy and its clinical significance in esophageal squamous cell carcinoma

Background: Many studies have focused on the relationship between dynamic changes in serum vascular endothelial growth factor (VEGF) and the prognosis of esophageal cancer (EC) patients undergoing chemo-radiotherapy (CRT). Few studies have reported the appropriate time-point for the measurement of VEGF during radiotherapy. In this study, we aimed to identify the appropriate time-point for VEGF measurement during radiotherapy among EC patients. Methods: Serum VEGF in 76 EC patients was determined before, during (per 10 Gy) and after radiotherapy. The levels were categorized into three groups depending on the VEGF changes: increased, stable and decreased. Results: The 1-year overall survival (OS) and progression-free survival (PFS) rates of the patients were 55.7% and 51.4%, respectively, with median OS of 15.8 months [95% confidence interval (CI): 10.4–21.2 months] and 12.5 months (95% CI: 7.6–17.5 months), respectively. There were 13 cases of recurrence within 2 years post-treatment. The 1-yr OS rates of the patients with increased, stable and decreased VEGF were 31.6%, 60.0% and 71.4%, respectively (P=0.034). Significant differences were noticed in the 1-yr PFS rates among those with increased, stable and decreased VEGF (P=0.039). The 1-yr local control (LC) rates showed no significant differences (P=0.306). Compared to those before radiotherapy, the serum VEGF levels of 19 patients were found to be increased at approximately 20–30 Gy during radiotherapy or post-radiotherapy. VEGF decreases were noticed in 21 cases at 20–30 Gy during radiotherapy. Conclusions: Serum VEGF changes could be used to predict the prognosis of EC patients undergoing CRT. It is appropriate to determine serum VEGF at 20–30 Gy during radiotherapy and post-radiotherapy among EC patients.