[Studies on para-aortic metastatic lymph nodes in gastric cancer after endoscopic injection of activated carbon particles].

When activated carbon particles are injected into the tissues, they are absorbed into the lymphatic capillary and reach to the regional lymph nodes. Utilising this property of the activated carbon, we injected small sized carbon particles (CH-44) around the gastric cancer using endoscope to examine para-aortic lymph node metastasis. Sixty eight patients with gastric cancer existing serosal invasion were subjected to extended radical gastrectomy dissecting para-aortic lymph nodes as well as regional lymph nodes. Twenty patients (29.4%) had para-aortic lymph node metastasis. Cumulative 5-year survival rate of these patients after surgery was 20.0 per cent. High incidence of metastasis in para-aortic lymph nodes was found in the lymph nodes larger than 4mm in diameter, but 15.9 per cent of lymph nodes less than 2mm in diameter had metastasis. Large lymph nodes occupied almost wholly by cancer cells were stained scarcely by activated carbon particles, but lymph nodes with moderate or slight metastasis were stained black well and this method was very useful for lymph node dissection, even for micro-lymph nodes which seemed to escape from naked eye at surgery.