Lymphatic Routes of Gastric Cancer Metastasis Elucidated by Triple Lymph Node Analysis

Abstract

Background: Although the development of lymphatic invasion by gastric cancer has been solved using 'solitary lymph node metastasis' research, few facts are known about the sequential flow following the sentinel station. Aim: In this study, we investigate the lymphatic spread of gastric cancers using 'triple lymph nodes metastases' analysis. Methods: During January 2001 and December 2015, 402 subsequent patients with gastric cancer underwent gastrectomy with standardized lymph node dissection at our institute. Among them, lymph node involvement was revealed in 234 patients by a histopathological study. The lymphatic spread of gastric cancer was analyzed theoretically based on the probability of additional lymph node metastases from each station. Results: The numbers of cases were 64, 41, 17, 23, 17, 13 and 59 according to the number of metastases of 1, 2, 3, 4, 5, 6 and 7 or more, respectively. The lesser curvature lymph node (#3) was the key station and skip metastasis was sometimes seen in lymph nodes of the intermediate region at the solitary lymph node metastasis stage. Some lymphatic flows were demonstrated by double and triple lymph node metastasis analysis, especially many flows from perigastric toward intermediate regions. Conclusion: This study demonstrated theoretically a lymphatic route for gastric cancer cells using a novel methodology. The results may be applicable to making preoperative diagnosis and for deciding on optimal lymph node dissection in gastric cancer surgery.