Expression of CEA mRNA and CK-20 mRNA in peritoneal washings of patients with gastric cancer and its clinical significance

Objective To explore the clinical value of CEA mRNA and CK-20 mRNA expressions in peritoneal washings for gastric cancer.Methods Peritoneal irrigating solution or abdominal dropsy was collected from 80 patients with gastric cancer and 10 patients with benign lesion of stomach.Nested RT-PCR and cytopathological examination were used to determine the CEA mRNA and CK-20 mRNA expressions.Meanwhile,the gastric cancer cell line SGC-7901 served as a positive control.Results Positive expression of CEA mRNA was in 42 patients(52.5%),of CK-20 mRNA was found in 46 patients(57.5%),and of CK-20 mRNA and CEA mRNA was in 56 patients(70.0%) by nested RT-PCR.However,positive expression of both CEA mRNA and CK-20 mRNA was found in 22 patients(27.5%)by cytopathological examination.There was a close correlation between CEA mRNA and CK-20 mRNA expressions lymph node metastasis and TNM staging in gastric cancer patients(P0.05).Conclusions Detecting CEA mRNA and CK-20 mRNA in peritoneaI washings by nested RT-PCR can improve the sensitivity and specificity of intraperitoneal free cancer cells(IFCCs) detection in peritoneal washings,and it is promising as a valuable method for predicting peritoneal metastasis in gastric cancer,then it can provide the basis for therapy.