Validation study of sentinel lymph node mapping using radio- and dye-guided methods in gastric cancer: 431 cases at a single institution.

Abstract

76 Background: Some papers have reported that sentinel lymph node (SLN) concept can be applied in patients with early gastric cancer, in particular clinically T1N0M0 or T2N0M0 with a tumor diameter of 4cm or less. Little is, however, available on the SLN study with the other criteria than listed above. The aim of the present work was to investigate the accuracy of the SLN biopsy of gastric cancer with various stages and evaluate the indication for SLN navigated gastrectomy. Methods: A total of 431 consecutive patients were diagnosed with operable gastric cancer during the period April 1999 through December 2007. Reasons for inclusion were, in principle, T1N0M0 or T2N0M0 gastric cancer. However, several patients diagnosed preoperatively with T3N0M0, T2N1M0, remnant gastric cancer, multiple gastric cancers and additional treatment after endoscopic therapy were also enrolled in this study according to their request. All patients underwent a radical gastrectomy with SLN mapping with an informed consent. The SLNs were identified using both radio-guided and dye-guided method. Results: Detection rate of hot and/or blue node was 95.8% (413/431). The accuracy of metastatic status based on SLN was 97.6% (403/413). In six of 10 false-negative cases, some clinical backgrounds and problems were present; scirrhous gastric cancer, the tumor penetration of serosa, multiple lesions, remnant gastric cancer after partial resection and the technical issue of tracer injection. Nine of these 10 false-negative cases had the metastatic lymph nodes within only the sentinel basins. Specifically, in the group of clinically T1N0M0 untreated gastric cancer with a tumor diameter of 4 cm or less, there were only 3 false- negative cases. In addition, all the metastatic lymph nodes of the 3 cases located within the sentinel basins. Conclusions: Our study suggested that SLN concept for untreated early gastric cancer could be validated. The sentinel basin dissection might be used to advantage to improve curativity for gastric cancer. No significant financial relationships to disclose.