Effect Of Total Lymph Node Dissection On Survival And Prognosis Of N1 Gastric Cancer Patients

Objective: To investigate the effect of total number of lymph nodes dissection on survival and prognosis of N1 stage gastric cancer patients,and to establish the minimum requirement of total number of lymph nodes dissected in N1 stage gastric cancer patients.Methods:The clinicopathological data of 243 gastric cancer patients with pathological stage N1 treated in the First Affiliated Hospital of Hainan Medical University from January 2012 to December 2020 were retrospectively collected.The total number of lymph node dissection in all gastric cancer patients was greater than or equal to 16.According to the number of lymph node dissection,the patients were divided into 4 groups: 16-20 in group A,21-25 in group B,26-30 in group C,and more than 30 in group D.To analyze the effect of total number of lymph node dissection on survival and prognosis of gastric cancer patients.Chi-square test was used to verify the correlation of clinicopathological features of each group.Kaplan-meier method was used to analyse the survival,log-rank method was used for significance test,Cox model was used for multivariate prognostic analysis.The prognostic factors of stage N1 gastric cancer were analyzed and the minimum number of lymph node dissection was determined.Results: 1.The clinicopathological characteristics of 243 patients with N1 stage gastric cancer in different lymph node dissection groups were analyzed.The results showed that there was no statistical significance in gender,age,maximum tumor size,Borrmann classification,histological type,T stage,TNM stage and tumor deposit in the four groups.2.Univariate survival analysis showed that age,Borrmann type,T stage,total number of lymph nodes and tumor deposit were significantly correlated with prognosis of N1 gastric cancer patients(P <0.05),the 5-year cumulative survival rates of group A,B,C and D were 29.3%,53.4%,60.2% and 67.0%,respectively.The prognosis of group A was worse than that of group B,C and D,and there was no statistical difference in the prognosis of group B,C and D.Multivariate prognostic analysis of all patients showed that age(HR=2.160,95%CI:1.442-3.235,P<0.001),total number of dissected lymph nodes(HR=0.745,95%CI:0.626-0.888,P<0.001),and tumor deposit(HR=2.475,95%CI: 1.674-3.657,P<0.001)were independent prognostic factors for N1 patients.Conclusions: In N1 stage gastric cancer patients,increasing the total number of lymph nodes dissection can improve the survival prognosis of gastric cancer patients,and at least 21 lymph nodes should be dissected in N1 patients.