[Study of para-aortic lymph node metastasis for advanced gastric cancer on consecutive lymph node slices].

Para-aortic lymph nodes (No. 16) from 21 patients with advanced gastric cancer who underwent extensive lymph node dissection, were sliced consecutively at intervals of 50 mu to study minute metastasis of No. 16 lymph nodes. Twenty-six of 30 metastatic lymph nodes had minute involvement, in which carcinoma cells were detected in marginal sinus of lymph node, microscopically. The rate of the metastases to No. 16 lymph nodes was 19% among N0-3 cases by conventional method (not consecutive slices). On the contrary, the percentage of metastasis to No. 16 lymph nodes by consecutive slices was 33% among N0-3 cases. Therefore, No. 16 nodes are involved in metastasis at high rate at operation and the extensive lymph node dissection including No. 16 nodes (R4) will be recommended to prevent lymph node recurrence caused by such a minute metastasis.