Molecular detection of circulating cancer cells during surgery in patients with biliary-pancreatic cancer

Background: It remains unclear whether surgical treatment for biliary-pancreatic cancers provokes the hematogenous dissemination of cancer cells. The aim of this study was to detect circulating cancer cells in the blood stream before and during tumor resection for biliary-pancreatic cancer. Methods: We analyzed blood samples obtained perioperatively from the portal vein, peripheral artery, and superior vena cava, using a carcinoembryonic antigen (CEA)-specific nested reverse transcriptase-polymerase chain reaction. Results: CEA-mRNA expression was detected in the blood of 21 (52.5%) of 40 patients with biliary-pancreatic cancer. The patients with detectable CEA-mRNA expression included 8 (42.1%) of 19 with bile duct cancers and 13 (61.9%) of 21 with pancreatic cancers. CEA-mRNA expression was not detected in blood obtained from 15 healthy volunteers and 15 patients with benign disease. The positive rate of CEA-mRNA of advanced clinical stage (TNM pStage III and IV) showed higher than that of early stage (pStage I and II; P <0.05). Tumor resection increased significantly the positive rates of CEA-mRNA in the blood stream of three kinds of vessel. Conclusions: Surgical procedures provoke the hematogenous dissemination of cancer cells perioperatively. Therefore, new strategies during operations to prevent liver metastases are needed to improve the survival of patients with biliary-pancreatic cancer.