Abstract: Objective:To investigate the dynamic change of peripheral blood prostaglandin E2(PGE2) level before and after operation and its clinical significance in patients with colorectal carcinoma.Methods:Sixty-one patients with colorectal carcinoma were divided into Non-distant metastasis group 46 cases and distant metastasis 15 cases,thirty healthy people formed the control group.Among 61 patients,forty-one,eleven and nine cases were treated with resection,palliative resection and laparotomy,respectively.The PGE2 levels of peripheral blood and tumor tissue before and after operation in patients and normal colorectal mucosa and peripheral blood in healthy people were detected.Results:The PGE2 levels of peripheral blood before operation in patients with colorectal carcinoma were obviously increased,the PGE2 levels of patients with stage D were significantly higher than that in stage A,B and C(P 0.01).The level of peripheral blood PGE2 in patients with Non-distant metastasis was positive correlation with tumor size(P 0.01).The level of PGE2 in tumor tissue was significant higher than that in normal colorectal mucosa(P 0.01).The PGE2 levels of peripheral blood after were operation decreased significantly,the PGE2 level difference between the patients treated with resection and healthy people was not statistical significance(P 0.05).The PGE2 levels of patients treated with palliative resection and laparotomy were significantly higher that in control group(P 0.01).Conclusions:The high PGE2 level of peripheral blood in patients with colorectal carcinoma originated from the tumor.The dynamic detection of peripheral blood PGE2 may be considered as an auxiliary index in predicting the recurrence and metastasis of colorectal carcinoma after radical resection.