Clinical usefulness of intraoperative sentinel-node biopsy in gastric cancer

Minimally invasive surgery has been used to improve the quality of life after operation in patients with gastric cancer. Sentinel-lymphnode biopsy can help to limit the extent of lymph node dissection, but the diagnostic and therapeutic usefulness of this technique has not been accurately evaluated in gastric cancer. This study was designed to clarify the role of intraoperative sentinel-node biopsy in patients with gastric cancer.

We were conducted to evaluate 1) mapping sentinel nodes according to tumor location 2) comparison sentinel node metastases as assessed by frozen section, permanent section (HE stain) and immunohistochemical diagnoses, and 3) comparison non-sentinel node metastases as assessed by permanent section (HE stain) and immunohistochemical diagnosis.

All sentinel nodes were identified in the regional perigastric lymph node group close to the tumor. Four of the 43 sentinel lymph nodes were positive for metastasis. Similar diagnostic results were obtained by the 3 different procedures. Lymph node metastasis was found in 10 (4 sentinel nodes and 6 non-sentinel nodes) of 779 lymph nodes (1.28%) on HE staining. Immunohistochemical studies revealed a similar number of positive sentinel nodes as that obtained on HE staining, but identified metastases in 15 in non-sentinel nodes in 2 patients, as compared with only 6 nodes on HE staining. In one patient, sentinel nodes at No. 1 and No. 3 were negative for metastasis, whereas non-sentinel lymph nodes at NO. 3 were positive for metastasis. The other patient had negative sentinel nodes at No. 3 and No. 4d, but positive non-sentinel nodes at No. 4d.

The results of this small study do not yet provide a firm basis for recommending that sentinel-node biopsy is used to reduce the extent of lymph node dissection.