[Sentinel node concept and its application for cancer surgery].

The sentinel node is the first lymph node that drains a primary tumor. A negative sentinel lymph node accurately predicts the absence of metastasis to any other regional lymph nodes. A higher rate of feasibility, sensitivity, specificity, and diagnostic accuracy in sentinel lymph node mapping has been demonstrated of cancer of the breast, penis, and vulva and in malignant melanoma. Intraoperative endoscopic lymphatic mapping, which we developed for gastric cancer in 1994, was also useful in accurately predicting nodal status in 163 early-stage gastric cancer patients: the rate of sensitivity, specificity, and accuracy was 91%, 100%, and 98%, respectively. Therefore if the sentinel lymph node biopsy is free of metastasis, limited surgery such as wedge resection, segmental resection, pylorus-preserving gastrectomy, or proximal gastrectomy is indicated. The tumor-free sentinel lymph node allows dissection of regional lymph nodes to be avoided and results in an improved quality of life in postoperative patients. In addition, sentinel lymph node biopsy has the advantages of enhancing staging accuracy, detecting micrometastases, and identifying variations in the regional lymphatic basin. Further progress may change the mode of nodal dissection and the indications for adjuvant chemotherapy for cancer.