Sentinel node concept in gastric carcinoma

To assess the applicability of the sentinel node concept to gastric carcinoma. The location of metastatic lymph nodes was analyzed retrospectively in 119 patients with gastric carcinoma in whom metastasis was limited to one or two nodes. Intraoperative lymphatic mapping was attempted in 62 patients using indocyanine green injected endoscopically into the gastric submucosa adjacent to the tumor. Metastatic lymph nodes were distributed beyond the perigastric area in 4% of patients with a single node involved. The positive node was located along the greater curvature in 21% of the patients with a tumor on the lesser curvature. Two patients had a metastatic node totally occupied by cancer tissue. In 16% of patients with two nodes involved, a positive node was located on both the lesser and greater curvatures. Lymphatic mapping was successful in all subjects. A larger number and wider distribution of green-stained nodes were observed in patients injected with 8 ml of indocyanine green solution than in those injected with 4 ml. No metastasis was observed in any nodes in 47 (96%) of the 49 patients who had no metastasis in green nodes. In one patient showing metastasis in non-green nodes without metastasis in green nodes, the positive nodes were totally occupied by cancer tissue. Our results showed the complexity of lymphatic streams within and from the stomach. Lymphatic mapping using indocyanine green can be a tool for identifying sentinel nodes in gastric carcinoma although lymph nodes occupied by cancer tissue may not be detected by this technique.