Use of RT-PCR for CK20 and CEA mRNA to Detect of Micrometastasis in the Draining Venous Blood and the Peritoneum in Gastric Cancer Patients

ABSTRACT

PURPOSE: The benefits of the "no-touch" isolation technique that is usually performed to prevent the circulation of tumor cells are not evident. The aim of this study was to determine whether the no-touch isolation technique for treating gastrointestinal cancers could prevent the circulation of tumor cells detected by reverse transcriptase polymerase chain reaction (RT-PCR). Matrials and Methods: By using RT-PCR to amplify mRNAs for two specific epithelial markers, carcinoembryonic antigen (CEA) and cytokeratin 20 (CK-20), we examined 34 gastric cancer patients who had been histologically diagnosed and 22 patients had undergone serosal and peritoneal brushing. RESULTS: In 10 (29.4%) of the 34 gastric cancer patients, we detected CK20 mRNA before manipulation, and in 17 (51.5%) of those patients, after we detected it. The density of the CK20 mRNA band was increased in 11 cases (33.3%) and the density was decreased in 2 cases (6.1%). In 16 (48.5%) of the 34 gastric cancer patients, we detected CEA mRNA before manipulation, and in 17 (51.5%) patients after we detected it. The density of the CEA mRNA band was increased in 8 cases (24.2%) and decreased in 3 cases (9.1%). CONCLUSION: These result suggest that the "no-touch isolation technique" might be useful when operating on advanced gastric cancer patients and that serosal or Douglas pouch brushing can be used to determine the status of micrometastasis.