Objective:To investigate the effects of anesthesia and postoperative analgesia with different methods on the differentiation of human helper T cells in the esophageal carcinoma patients undergoing thoracic surgery. Methods:Sixty esophageal carcinoma patients,classified as ASA physical status Ⅰ~Ⅱ,scheduled for elective thoracic surgery were randomly divided into three groups with 20 cases in each group:groupⅠreceived general anesthesia during thoracic surgery and patient-controlled intra-venous analgesia(PCIA) with fentanyl postoperatively;groupⅡunderwent general anesthesia plus thoracic epidural anesthesia(TEA) during thoracic surgery and received the same analgesia method as groupⅠpostoperatively; group Ⅲ were anesthetized as groupⅡ and received patient-controlled epidural analgesia(PCEA) with fentanyl and ropivacaine postoperatively. Venous blood samples for measurement of IFN-γ(as a marker of Thl cells) and IL-4(as a marker of Th2 cells)were taken before the induction of anesthesia and at set intervals until 48 h postoperatively. T helper cell subsets were quantified by using flow cytometry,and the ratio of Thl to Th2 cells was calculated. Results:The analgesial effects were similar among the groups. The Thl/Th2 ratio in all groups were decreased significantly after completion of surgery compared with baseline levels(P < 0.05). Group comparison,at T2 the Thl/Th2 ratio in GroupⅡ and Ⅲ higher than that in groupⅠ. In group Ⅲ the Thl/Th2 ratio at T3 and T4,were higher than those in groupⅡ. Conclusion:These findings show that general anesthesia combined with thoracic epidural anesthesia and PCEA may inhibit Th0 cells to differentiate into Th2 cells.