Perigastric lymph nodes with metastasis in gastric cancer

BACKGROUND/AIMS: We analyzed the significance of metastasis to the subdivided perigastric lymph node stations according to the distance from the primary gastric cancer, and the appropriateness of the recent change in the Union Internacional Contra la Cancrum (UICC) tumor node metastasis (TNM) system. METHODOLOGY: Gastrectomy was performed in 753 patients with gastric cancer. The perigastric lymph nodes were divided into 6 stations according to the Japanese classification. These were subdivided into 2 categories according to the distance from the primary tumor: -1, nodes within 3cm of the edge of the tumor; and -2, nodes more than 3cm from the edge of the tumor. Survival rates were calculated with the Kaplan-Meier method, and the difference between each group was evaluated by the log-rank method. RESULTS: The frequency of metastasis to the subdivided perigastric lymph node stations, numbered 1-1 to 6-2, varied between 10.0% and 41.1%. The 5-year survival rate of the patients with positive 6-1 lymph node was higher than that of the patients with positive 6-2 lymph node (31.5% and 17.5%, P=0.0032). There were no statistically significant differences in survival between subgroups of patients who had metastatic lymph node in the other 5 stations. The frequency of metastasis to other regional lymph nodes in patients with N2 perigastric lymph nodes was higher than that in patients with N1 perigastric lymph nodes. CONCLUSIONS: Subdivision of the perigastric lymph nodes had little advantage. Elimination of the old system of classifying perigastric lymph nodes according to distance from the tumor is appropriate.