[Prognostic value of metastatic lymph node ratio in gastric cancer patients undergoing radical gastrectomy]

To assess the prognostic value of metastatic lymph node ratio in gastric cancer patients undergoing radical gastrectomy (D2).

Prognostic analysis of 1042 gastric cancer patients undergoing radical gastrectomy (D2) was performed based on metastatic lymph node ratio (MLR), the N staging in the 6th and 7th edition of UICC staging system respectively. Homogeneity, discriminatory ability, and gradient monotonicity of these three staging methods were compared using linear trend χ(2), likelihood ratio χ(2) statistics and Akaike information criterion (AIC) calculations, respectively. The area under the ROC curve (AUC) was calculated to compare the prognostic value of these three staging methods.

The 5-year survival rate of 1042 patients was 47.5%. The metastatic lymph node ratio (P<0.01) and N staging of the 7th edition UICC (P<0.05) were independent prognostic factors according to univariate and multivariate analyses. The AUC was 0.754 in MLR staging group, higher than that in N staging of the 6th (0.692) and 7th (0.705) edition of UICC group. Compared to the 6th and 7th edition of UICC N staging group, homogeneity and linear curve were better and AIC value was lower in MLR staging group (7240.017 vs. 7364.073 and 7325.731).

Prognostic value of MLR staging is better than that of UICC N staging for patients undergoing radical gastric cancer resection. The MLR staging can be a new method of lymph node staging for gastric cancer patients.