Abstract: Objective To establish a method for quantitative detection of CEA mRNA in the peripheral blood and lymph nodes of patients with cdorectal cancer.Methods Real-time RT-PCR was taken to detect the CEA mRNA comparative expression in lymph node,as well as in the peripheral blood.and ECLIA was taken to detect the value of CEA.Results 50 cases of colorectal cancer CEA mRNA positive expression in peripheral blood before surgery was 84%,and the normal control group(10 persons without positive),the difference was statistically significant(P＜0.01);CEA-positive rate of 22% compared with the positive expression rate of CEA mRNA difference was statistically significant(P＜0.01);CEA mRNA lymph node positive rate 32.3%,compared with the positive rate in peripheral blood CEA mRNA difference was statistically significiant(P＜0.01).Conclusions The method of SYBRGREEN real-time PCR is established for the detection of CEA mRNA expression in patients with colorectal cancer.The positive rate of CEA mRNA is relatively higher in peripheral blood of preoperative patients than that in lymph nodes,and is relatively higher than the value of CEA.It is useful for the preoperative diagnosis of patients with colorectal cancer.

Key words: CEA mRNA, CEA, Real-Time PCR, ECLIA, Peripheral blood, Lymph nodes