Detection And Prognosis Of “Cancer Leakage” In Laparoscopic Distal Gastrectomy

Objectives:To conform the existence of Metastasis V and that gastric mesentery had a barrier effect on tumor cells.To prove that D2 + CME can ensure the integrity of gastric mesentery.Methods: Gastric mesentery resected by D2+CME were collected,pathology slice were used to search metastasis V and to check the integrity of gastric mesentery.The serosa layer of gastric mesentery was obtained and used as a barrier for the cell migration assay to conform whether the tumor cells could pass through the serosa.Results: The Metastasis V was found by HE staining in the mesentery of gastric cancer patients.By HE and Masson staining,it was found that the serosa layer on the surface of gastric mesentery was intact.Through cell migration assay,we found that tumor cells could pass through the chamber in the absence of membranes,but not in the area covered by membranes.Conclusions: There exists Metastasis V in the gastric mesentery.The gastric mesentery has a barrier effect on tumor cells.Laparoscopic D2+CME can ensure the integrity of the mesentery.Objectives: To compare the incidence of "cancer leakage" in laparoscopic D2 and(D2+CME)for distal gastric cancer,and explore the risk factors affecting "cancer leakage" and prognosis of patients.Methods: Patients with gastric cancer who had a conventional D2 or(D2+CME)laparoscopic distal gastrectomy between April 2015 and April 2018 were included in the study.Intraoperative peritoneal washings were collected before and after tumour resection.Reverse transcriptase–quantitative real-time PCR for carcinoembryonic antigen(CEA)was used to assess the presence of gastric cancer cells.Patients were followed up regularly and the survival rates of patients undergoing D2 and(D2+CME)laparoscopic distal gastrectomy were compared by Kaplan-Meier survival curve analysis.Multivariate analysis was used to determine the independent prognostic indicators affecting the "cancer leakage" and prognosis of these patients.Results: 210 eligible patents between April 2015 and April 2018 were enrolled in this study,including 103 patients in the D2 group and 107 in the D2+CME group,respectively.Of the 210 peritoneal fluid samples obtained before gastrectomy,119 had low CEA expression indicative of no cancer cells,including 60 and 59 in the D2 group and D2+CME group respectively.After gastrectomy,high CEA expression was detected in 23 of the 60 samples(38.3 percent)from patients in the D2 group,and in 9 of the 59 samples(15.3 percent)from the D2+CME group(P=0.005),and the mean CEA expression level after gastrectomy was lower in the D2+CME group than in the D2 group(P=0.046).In patients with low CEA expression before gastrectomy,disease-free survival and overall survival in the D2+CME group were better than those in the D2 group(P=0.016,P=0.044).Surgical procedure,depth of tumor invasion and lymph node metastasis are independent risk factors affecting “cancer leakage”;surgical procedure,“cancer leakage” and depth of invasion are independent risk factors for gastric cancer patients.Conclusions:D2+CME can reduce the “cancer leakage” during curative surgery.surgical procedure and “cancer leakage” affect the prognosis of patients,and can be used as an important prediction factor for gastric cancer patients prognosis.Objectives: To compare the difference of cytology,immunohistochemistry,cellcollector and RT-PCR in detecting intraperitoneal free cancer cells in patients with gastric cancer.Methods: Intraoperative peritoneal washings were collected before and after laparoscopic gastrectomy.Cell collector,immunohistochemistry and RT-PCR were used to assess the presence of gastric cancer cells.Results: Intraoperative peritoneal washings were collected from 18,15 and 8 patients before and after gastrectomy.Intraperitoneal free cancer cells were detected by cytology,immunohistochemistry,cellcollector and RT-PCR.Of the 18 patients,the detection rates of intraperitoneal free cancer cells by RT-PCR were 44.4% and 72.2% before and after surgery,while the detection rates by cytology were only 22.2% and 11.1% before and after surgery in the same patients,which were significantly lower than that by RT-PCR.Of the 15 patients,the detection rates of intraperitoneal free cancer cells by RT-PCR were 46.7% and 66.7% before and after gastrectomy,while the detection rate by immunohistochemistry were 20.0% and 13.3%,which were significantly lower than that by RT-PCR.Then,we validated the feasibility and sensitivity of cell collector in detecting tumor cell lines in vitro,and conformed that CEA and CK20 could be used as tumor markers in this method.Cell collector was used in the 8 patients.The results showed that there was no significant difference between cell collector and RT-PCR in detecting intraperitoneal free cancer cells.Conclusions:The efficiency of cytology and immunohistochemistry in detecting intraperitoneal free cancer cells of patients with gastric cancer was lower than that of RT-PCR,but there was no significant difference between cell collector and RT-PCR.