Abstract: To study the changes and clinical significance of serum carcinoembryonic antigen (CEA), squamous cell carcinoma-associated antigen (SCC) and vascular endothelial growth factor (VEGF) levels before and after intensity-modulated radiotherapy in patients with esophageal cancer, 50 cases of esophageal cancer treated by radiotherapy from January 2016 to December 2017, in our hospital were taken as the study group and 30 cases of healthy people as the control group. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum CEA, SCC, and VEGF levels in patients before and after radiotherapy. the changes of the above indicators before and after intensity-modulated radiotherapy were analyzed, as well as their relationship with clinical TNM stage and tumor infiltration. The results showed that the serum CEA, SCC, and VEGF levels of patients before IMRT were significantly higher than those after radiotherapy (p<0.05). After treatment, the serum levels of the above-mentioned indicators were significantly decreased (p<0.05), but still higher than that of the control group. TNM patients with different clinical stages have significant differences in the above indicators, of which stage III is the highest; patients with different tumor invasion depths also have significant differences in the above indicators, of which T4 stage is the highest (p<0.05). These indicate that the serum levels of CEA, SCC, and VEGF in esophageal cancer patients are different in the depth of tumor invasion, different clinical TNM stages, and before and after intensity modulated radiotherapy. It's important for formulating personalized treatment plans for esophageal cancer patients and observing the therapeutic effect.

Key words: Esophageal cancer, Radiotherapy, CEA, SCC, VEGF