These results indicate that serum HMGB, IDO, CEA and SCC-Ag may have similar roles in predicting the progression of ESCC, the combined detection of serum HMGB1 and IDO has a higher predictive value than the combined detection of CEA and SCC-Ag, and the combined detection of the four is more valuable in predicting the progression of ESCC. This evidence concerns the gene IDO1 and esophageal squamous cell carcinoma.