Metastatic Lymph Node Ratio (Nratio) is an Independent Parameter of TNM Classification in Gastric Cancer Prognosis

Abstract

Objective: Lymph node metastasis is known to be an important prognostic factor in the gastric cancers. In different staging classifications, the nodal involvement is evaluated in terms of the location and/or number of the metastatic lymph nodes. However, in the Western countries the minimum number of 15 lymph nodes required for an evaluation has been obtained in only 30% of the radical resections performed in the gastric cancer cases; and due to the heterogeneous survival responses in the same stage patients and the phase shifts, use of the metastatic lymph node ratio (N-ratio) rather than of the total number of positive nodes has recently been recommended for the nodal evaluation. In this study, our main objective is to retrospectively analyze the effect of the prognostic parameters to the five-year survival in the gastric cancers, and to particularly investigate the prognostic value of the N-ratio.