Prognostic Significance of Ratio of Metastatic Lymph Nodes (MLNR) to Total Lymph Nodes Harvested in Squamous Cell Carcinoma of Esophagus

Introduction Esophageal cancer is an aggressive disease with features of poor prognosis and increasing incidence. Survival varies widely according to cancer location, extent, spread and treatment. Presence of lymph node (LN) metastases in patients with esophageal cancer has important prognostic implications. Despite the prognostic significance of identifying LN metastases in patients with esophageal cancer, the minimum number of LNs that need to be removed during surgery is controversial. Recently Metastatic Lymph Node Ratio (MLNR) is considered as an important prognostic factor. Aim and objectives- To know the prognostic significance of MLNR in patients with carcinoma of esophagus and to compare TNM staging based OS with MLNR based OS, and to study if MLNR based OS is significant as compared to TNM based OS Material and methods This study is an experimental, Prospective and retrospective clinical study during a period of 3 years from between January 2012 and December 2015 at a tertiary cancer center in South India. All patients were staged in accordance to the 7th edition of AJCC. All patients were operated by Trans Hiatal Esophagectomy (THE). Patients were grouped according to N stage which was further sub grouped as N0, N1, N2 and N3 depending on number of positive LN. Patients were also grouped according to MLNR into three subgroups as L0, L1, and L2, depending on MLNR. OS was calculated in all subgroups of N and all subgroups of L. Result- results of this study showed that MLNR as an important prognostic factor for OS of esophagus cancer. OS according to TNM staging was found to significant among all four subgroups of N (N0, N1, N2, N3). OS according to MLNR was also found to significant among all three subgroups L (L0, L1, L2). Comparison of OS in TNM and MLNR groups was found to be significant. Different patients in the same TNM group showed different OS based on their MLNR. Hence MLNR can be considered as an important prognostic factor in determining OS in esophagus cancer.