Ratio of Metastatic to Examined Lymph Nodes, a Helpful Staging System and Independent Prognostic Factor of Esophagogastric Junction Cancer

BACKGROUND The incidence of the esophagogastric junction cancer is growing rapidly. The purpose of this study is to clarify the outcome of the ratio between metastatic and examined lymph nodes in esophagogastric junction cancer patients with or without 7 examined lymph nodes. METHODS A total of 3,481 patients who underwent operation are identified from the Surveillance, Epidemiology, and End Results database. Different lymph nodes resected groups are analyzed to test the lymph nodes ratio factor. RESULTS There are 2522 patients with 7 or more lymph nodes resected and 959 patients with less than 7 lymph nodes resected. Lymph nodes ratio and lymph node involvement are independent prognostic factors. But the lymph nodes ratio categories have a better prognostic value than the lymph node involvement categories. Compared with lymph node involvement categories, lymph nodes ratio categories represent patients with more homogeneous overall survival rate. CONCLUSIONS This study defines that the lymph nodes ratio is an independent prognostic factor for esophagogastric junction cancer. The lymph nodes ratio can prevent stage migration and may be a helpful system to predict the prognosis of esophagogastric junction cancer patients.