Prognostic impact of metastatic lymph node ratio on gastric cancer after curative distal gastrectomy

AIM:To investigate the prognostic impact of metastatic lymph node ratio(rN) on gastric cancer after curative distal gastrectomy.METHODS:A total of 634 gastric cancer patients who underwent curative resection(R0) of lymph nodes at distal gastrectomy in 1995-2004.Correlations between positive nodes and retrieved nodes,between rN and retrieved nodes,and between rN and negative lymph node(LN) count were analyzed respectively.Prognostic factors were identif ied by univariate and multivariate analyses.Staging accuracy of the pN category(5th UICC/TNM system) and the rN category was compared according to the survival rates of patients.A linear regression model was used to identify the relation between rN and 5-year survival rate of the patients.RESULTS:The number of dissected LNs was related with metastatic LNs but not related with rN.Cox regression analysis showed that depth of invasion,pN and rN category were the independent predictors of survival(P < 0.05).There was a signif icant difference in survival between LN stages classif ied by the rN category or by the pN category(P < 0.05).However,no signif icant difference was found in survival rate between LN stages classif ied by the pN category or by the rN category(P > 0.05).Linear regression model showed a signif icant linear correlation between rN and the 5-year survival rate of gastric cancer patients(β = 0.862,P < 0.001).Pearson's correlation test revealed that negative LN count was negatively correlated with rN(P < 0.001).CONCLUSION:rN category is a better prognostic tool than the 5th UICC pN category for gastric cancer patients after curative distal gastrectomy.Increased negative LN count can reduce rN and improve the survival rate of gastric cancer patients.

Superiority of metastatic lymph node ratio to the 7th edition UICC N staging in gastric cancer

AIM:To compare and evaluate the appropriate prog-nostic indicators of lymph node basic staging in gastric cancer patients who underwent radical resection.METHODS:A total of 1042 gastric cancer patients who underwent radical resection and D2 lymphadenectomy were staged using the 6th and 7th edition International Union Against Cancer(UICC)N staging methods and the metastatic lymph node ratio(MLNR)staging.Ho-mogeneity,discriminatory ability,and gradient mono-tonicity of the various staging methods were compared using linear trend χ2,likelihood ratio χ2 statistics,and Akaike information criterion(AIC)calculations.The area under the curve(AUC)was calculated to compare the predictive ability of the aforementioned three stag-ing methods.RESULTS:Optimal cut-points of the MLNR were cal-culated as MLNR0(0),MLNR1(0.01-0.30),MLNR2(0.31-0.50),and MLNR3(0.51-1.00).In univariate,multivariate,and stratified analyses,MLNR staging was superior to the 6th and 7th edition UICC N stag-ing methods.MLNR staging had a higher AUC,higher linear trend and likelihood ratio χ2 scores and lower AIC values than the other two staging methods.CONCLUSION:MLNR staging predicts survival after gastric cancer more precisely than the 6th and 7th edi-tion UICC N classif ications and should be considered as an alternative to current pathological N staging.

Prognostic impact of metastatic lymph node ratio in advanced gastric cancer from cardia and fundus

AIM: To investigate the prognostic impact of the metastatic lymph node ratio (MLR) in advanced gastric cancer from the cardia and fundus. METHODS: Two hundred and thirty-six patients with gastric cancer from the cardia and fundus who underwent D2 curative resection were analyzed ret- rospectively. The correlations between MLR and the total lymph nodes, positive nodes and the total lymph nodes were analyzed respectively. The influence of MLR on the survival time of patients was determined with univariate Kaplan-Meier survival analysis and mul- tivariate Cox proportional hazard model analysis. And the multiple linear regression was used to identify the relation between MLR and the 5-year survival rate of the patients. RESULTS: The MLR did not correlate with the total lymph nodes resected (r = -0.093, P = 0.057). The 5-year overall survival rate of the whole cohort was 37.5%. Kaplan-Meier survival analysis identified that the following eight factors influenced the survival time of the patients postoperatively: gender (χ2 = 4.26, P = 0.0389), tumor size (χ2 = 18.48, P < 0.001), Borrmann type (χ2 = 7.41, P = 0.0065), histological grade (χ2 = 5.07, P = 0.0243), pT category (χ2 = 49.42, P < 0.001), pN category (χ2 = 87.7, P < 0.001), total number of re- trieved lymph nodes (χ2 = 8.22, P = 0.0042) and MLR (χ2 = 34.3, P < 0.001). Cox proportional hazard model showed that tumor size (χ2 = 7.985, P = 0.018), pTcategory (χ2 = 30.82, P < 0.001) and MLR (χ2 = 69.39, P < 0.001) independently influenced the prognosis. A linear correlation between MLR and the 5-year survival was statistically significant based on the multiple lin- ear regression (β = -0.63, P < 0.001). Hypothetically, the 5-year survival would surpass 50% when MLR was lower than 10%. CONCLUSION: The MLR is an independent prognostic factor for patients with advanced gastric cancer from the cardia and fundus. The decrease of MLR due to adequate number of total resected lymph nodes can improve the survival.