Abstract
Objectives
Currently D2 lymph node dissection is considered as minimal extent of dissection in curative resection of gastric cancer. This study was conducted to investigated the patterns of lymph node metastasis of gastric cancer and to validate extent of lympn node dissection.
Methods
Among 117 patients with gastric cancer, 35 patients with early gastric cancer and 45 with advanced gastric cancer underwent curative gastric resection were enrolled in this study. Removed lymph nodes were classified as N1(1~6), N2(7~11), N3(12~16) and the boundary of dissection was classified as D1, D2, D3, D3+α according to classification of stomach cancer research association in Korea.
Results
The priportion of early gastric cancer was 30%(35/117). Average number of metas-tatic lymph nodes was 2 in stage II, 6 in stage IIIa, 13 in stage IIIb, 21 in stage IV(p<0.05). 2 patients with early gastric cancer had metastatic lymph node(N1) and their lesions were over 3.0cm in size, depressed in shape. In terms of differentiation, 25(62%) patients with stage I, D1 dissection was carried out in two(5%), D2 dissection in eleven(28%), D3 or D3+α dissection in twenty seven (67%). In the patients with over stage II, there was no D1 dissection, D2 dissection was performed only in 3(7%), D3 or D3+α dissection in 37(92%). Extended lymph node dissection was significantly much higher in advanced cases than in early cases. The average number of resected positive lymph nodes were higher in BORRMANN type III or type IV than in type II(p<0.01, p<0.05 respectively). All patients with positive N2 or N3 lymph nodes revealed the positive N1 lymph nodes. There were 2(25%) skipped metastasis among 8 patients with positive N3 lymph nodes.
Conclusion
At least D2 lymph node dissection is needed for curative resection of gastric cancer in the patients with possible metastasis of N1 lymph nodes, even in the those we early gastric cancer. D3 or D3+α dissection should be performed in the patients with possible metastasis of N2 lymph nodes among advanced gastric cancer, even in the patients without metastasis of N2 lymph nodes selectiely because of skipped metastasis.