[Features of metastasis in different lymph node groups and their significance in lymph node dissection in total gastrectomy for gastric cancer].

OBJECTIVE: To summarize the features of metastasis in different lymph node groups (from 1 to 16 groups) in gastric cancer patients treated by total gastrectomy, and evaluate their clinical significance in lymph node dissection. METHODS: The data of 73 gastric cancer patients with total gastrectomy and lymph node dissection from January 2004 to April 2006 were analyzed retrospectively. The lymph nodes were divided into 16 groups according to the 13(th) edition of gastric cancer treatment guideline of JGCA (The Japan Gastric Cancer Association). The metastatic rate and degree of dissected lymph nodes in these patients were compared. RESULTS: The metastatic rates of lymph node groups in these patients from lower to higher were as follows: group 15, 13/16, 14v, 12, 10, 9, 11, 8, 2, 6/7, 5, 1, 4, 3. The lowest was the 15(th) group lymph nodes (1.4%), the highest was the 3rd group (65.8%), with a statistically significant difference between those two groups (P < 0.01). The metastatic degrees of the lymph node groups from lower to higher were as follows: 13, 16, 1, 7, 6, 5, 12, 4, 11, 8, 2, 15, 9, 3, 10, 14v. There was a statistically significant difference between the lowest group of lymph node (13(th) group, 10.7%) and the highest (14v(th), 56.3%, P < 0.01). CONCLUSION: In the radical total gastrectomy for patients with gastric cancer, it is suggested that the regional lymph nodes with higher metastatic rate should be resected necessarily, and the group with a higher metastatic degree should be dissected completely. If the result of sentinel lymph node biopsy in the 3(rd) or 14v(th) group is negative, the operation extent can be reduced. If positive, it should be extended. When the biopsy result in the 13(th) or 16(th) is positive, palliative operation may be indicated. However, if the biopsy result is negative in the 13(th) or 16(th), but positive in the 14v(th) group, extended operation is indicated.