Objective: To investigate the clinical significance of the changes of D-dimer levels in patients with esophageal cancer. Methods: The plasma levels of D-dimer were measured pre- and postoperatively in 33 patients with esophageal cancer and 30 healthy subjects served as controls by the method of quantitative enzyme-linked immunosorbent assay (ELISA). Results: The mean preoperative plasma levels of D-dimer in the patients with esophageal cancer (1.98 mg/L(0.34 mg/L) were significantly higher than that of controls (0.33 mg/L(0.12 mg/L) (P<0.01). The D-dimer levels were remarkably elevated on the 1st day after operation (2.41 mg/L(0.55 mg/L) (P<0.0l). On the 3rd day the level of D-dimer began to stepwise descend and on the 14th day near to control. The preoperative levels of D-dimer were significantly correlated with the tumor size but had no association with tumor location. A stepwise increase in the mean DD levels was found with the tumor stage. Conclusion: The hypercoagulation and fibrinolysis have occurred in patients with esophageal cancer. The operative trauma could enhance the fibrinolysis in the patients with esophageal cancer. The measurement of the preoperative DD levels is considered to be useful for the preoperative staging of esophageal cancer. Objective: To investigate the clinical significance of the changes of D-dimer levels in patients with esophageal cancer. Methods: The plasma levels of D-dimer were measured pre- and postoperatively in 33 patients with esophageal cancer and 30 healthy subjects served as controls by The method of quantitative enzyme-linked immunosorbent assay (ELISA). Results: The mean preoperative plasma levels of D-dimer in the patients with esophageal cancer (1.98 mg/L (0.34 mg/L) were significantly higher than that of controls (0.33 Mg/L (0.12 mg/L) (P<0.01). The D-dimer levels were remarkably elevated on the 1st day after operation (2.41 mg/L (0.55 mg/L) (P<0.0l). On the 3rd A level of D-dimer began to stepwise descend and on the 14th day near to control. The preoperative levels of D-dimer were significantly correlated with the tumor size but had no association with tumor location. A stepwise increase in the mean DD levels Was found with the tumor stage. Conclusion: The hypercoagulation and fi The bridging has occurred in patients with esophageal cancer. The operative trauma could enhance the fibrinolysis in the patients with esophageal cancer. The measurement of the preoperative DD levels is considered to be useful for the preoperative staging of esophageal cancer.