The blocking effect research of complete block technique applied in radical gastrectomy for gastric antrum cancer        WANG Jun，GUO Feng-hua，MAO Xiang，et al.  Department of General Surgery，Huashan Hospital，Fudan University，Shanghai 200040，China
Corresponding author：WANG Zhi-ming，E-mail：wzhm824@126.com
Abstract    Objective    To study the effect of complete block technique for gastric antrum cancer on preventing intraoperative metastases of tumor cells. Methods    Seventy-six cases of gastric antrum cancer admitted between July 2008 and September 2010 at Huashan Hospital of Fudan University were selected in the study. All the cases were randomly divided into two groups and  performed radical gastrectomy with complete block technique (blocking group) and traditional radical gastrectomy (conventional group) respectively. Blood samples from the portal vein and peritoneal wash samples were obtained immediately after laparotomy and during surgical resection. RT-PCR was used to determine levels of carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20). Carbon nanoparticles were injected into the subserosa of the blocked region before resection to determine lymph flow out of the region or not in blocking group. Results    Before tumor resection，the positive rate of CEAmRNA and CK20 mRNA expression in portal vein blood was 10%（4/40）and 15%（6/40）in blocking group respectively and 8.3%（3/36）and 11.1% (4/36) in conventional group respectively. There was no significant difference between two groups (P>0.05). During tumor resection，the positive rate of CEA mRNA and CK20 mRNA expression in portal vein blood was 7.5%（3/10）and 15.0%（6/40）in blocking group respectively and 30.5% (11/36) and 36.0%（13/36）in conventional group respectively. There was significant difference between two groups (P<0.05). The difference was not statistically significant for peritoneal washes. Lymph nodes in the blocked area were fully black dyed while those out of the blocked region were normal. Conclusion    Complete block technique can effectively prevent free tumor cells being shed into blood and lymph circulation caused by surgical mobilization to reduce intraoperative metastases.