Sentinel lymph node mapping for gastric adenocarcinoma.

The optimal extent of regional lymphadenectomy for gastric adenocarcinoma remains a controversial topic. Traditional approaches have focused on various anatomical nodal stations to define the extent of resection. In this prospective trial, we update our experience with sentinel lymph node (SLN) mapping and biopsy to augment resection of nodal metastasis in gastric carcinoma. Twenty-seven patients with gastric cancer were enrolled. SLNs were identified with isosulfan blue, resected, and sent fresh to pathology for staining and evaluation. The procedure then continued with radical gastrectomy and celiac node dissection. SLNs were identified in all cases. The average patient age was 65 years, with 12 women and 15 men. Eighteen patients had pathology-confirmed nodal metastasis. Positive SLN were found in 15 (83%); three patients had a false negative SLN mapping procedure (17%). Accuracy rate was 88.9 per cent. SLN mapping and biopsy for gastric carcinoma is feasible. However, the negative predictive value is 75 per cent, and therefore caution should be considered in using lymphatic mapping to determine extent of regional lymphadenectomy. Additionally, our study shows no utility in identifying micrometastatic disease with immunohistochemical techniques. Although a promising modality, we do not recommend the clinical use of SLN mapping for gastric cancer.