Efficacy Of Inferior Mesenteric Artery Low Ligation With D3 Lymph Node Dissection In Sigmoid And Rectal Cancer Surgery:A Systematic Review And Meta-analysis

Objective: To compare low inferior mesenteric artery(IMA)ligation with D3 dissection(LLD3)with high IMA ligation(HL)for the treatment of colorectal cancer by evaluating survival benefit and safety.Methods: PubMed,Embase,the Cochrane Library,Web of Science,CBM,CNKI,VIP and WanFang were systematically searched for relevant articles which compared HL and LLD3 for sigmoid or rectal cancer published from the inception to May 2019.All statistical analyses were performed using Stata 14.Results: Fifteen studies were included in this analysis,eight Chinese and seven English literature..In oncology: there were no differences between groups for the number of harvested lymph nodes,either total or around root of IMA(WMD=0.08;95%CI=-1.16~1.32,WMD=-0.13;95%CI=-0.41~0.16,respectively).The number of harvested positive lymph nodes around root of IMA(WMD=1.407;95%CI=-1.53~4.34)and patients with metastatic lymph nodes root of the IMA(OR=1.302;95%CI=0.69~2.44),local recurrence rate(OR=1.17,95%CI=0.44~3.12),the 5-year OS(HR=1.21,95%CI=0.93~1.59),the 5-year DFS(HR=1.20,95%CI=0.62~2.34),pathological proximal margin(SMD=0.10;95%CI=-0.27~0.42),pathological distal margin(SMD=0.15;95%CI=-0.14~0.45)were not detected significant differences between two groups.In Safety : the incidence of anastomotic stenosis(OR=4.30;95%CI=0.96~19.32),the incidence of anastomotic hemorrhage(OR=1.02;95%CI=0.25~4.20)and the incidence of surgical-site infection(OR=0.81;95%CI=0.57~1.15),blood loss(SMD=0.01;95%CI=-0.08~0.10),time of first postoperative exhaust(SMD=0.07;95%CI=-1.12~1.27)were also not detected significant differences between two groups.The incidences of anastomotic leakage,urination dysfunction and ileus were significantly lower in patients treated with LLD3 than in those treated with HL(OR=1.69,95%CI=1.29 to 2.23;OR=2.45,95%C = 1.39 to 4.33;OR=1.54;95%CI=1.02 to 2.31,respectively).However,longer operation time was required in LLD3 group(WMD=-6.82,95%C =-12.58 to-1.06).Conclusions: LLD3 could obtain similar lymph node harvested and short-term efficacy,equivalent survival benefit to HL,and associates with lower incidence of leakage,urination dysfunction and ileus.So based on the current available evidence,LLD3 has been proven to have the advantages of the two standard ligation methods,and is more suitable for sigmoid and rectal cancer surgery.