Secondary sentinel lymph node tracing technique: a new method for tracing lymph nodes in radical gastrectomy for advanced gastric cancer

Objective： To explore the feasibility and clinical value of secondary sentinel lymph node （SSLN） tracing technique in radical gastrectomy for advanced gastric cancer （AGC）. Methods： From January 2009 to June 2011,247 patients who suffered from gastric angle cancer with metastasis in No. 3 group lymph nodes were divided randomly into groups A and B. Methylthioninium chloride was injected into the peripheral tissue of the metastatic No. 3 group lymph nodes of 138 patients in group A before tumor resections. SSLNs were traced and individual lymphadenectomies were carried out based on the biopsy results of the SSLNs. Standard D2 radical gastrectomies were carried out directly on 109 patients in group B. Postoperative follow-up and survival analysis were carried out for patients in both groups. Results： SSLNs were found in 114 （82.6%） patients in group A. Ninety of those patients （78.9%） demonstrated existing metastasis in SSLNs. According to Kaplan-Meier＇s method, the postoperative 3-year cumulative survival rates were 63.5% and 47.5%, and the median survival time were 40 and 36 months for the patients of groups A and B, respectively （P〈0.05）. Conclusions： The SSLN tracing technique is feasible in radical gastrectomy for AGC. It gives surgeons important information about the terminal status of lymph node metastasis and provides some scientific basis for individual lymphadenectomy.

New method of lymph node tracing in gastrectomy for advanced gastric carcinoma

Objective： The aim of this study was to explore a new method of lymph node tracing in radical gastrectomy for advanced gastric carcinoma （AGC）. Methods： Ninety-two patients who suffered from gastric angle carcinoma with metastasis in No. 3 group lymph nodes were carried out radical gastrectomy. During the operation methylene blue was injected inside or around the circum of the metastatic No. 3 group lymph nodes. Secondary sentinel lymph nodes （SSLNs） were the near- est blue lymph nodes to No. 3 group lymph nodes that were searched in 5 to 10 rain after injecting methylene blue. These SSLNs were resected and carried out hematoxylin-eosin （HE） staining as well as immunohistochemistry （IHC） staining to demonstrate whether there were metastasis. Results： SSLNs were found successfully in 76 patients with a positive rate of 82.6% （76/92） by methylene blue staining, among which, 34 patients were demonstrated existing metastasis in SSLNs by HE staining, 26 patients were demonstrated existing metastasis in SSLNs by IHC staining which were not demonstrated exist- ing metastasis by HE staining. Totally, 60 patients were demonstrated existing metastasis in SSLNs by HE staining and IHC staining with a positive rate of 78.9% （60/76）. 136 SSLNs were found in total and 104 SSLNs were demonstrated existing metastasis with a positive rate of 76.4% （104/136）. There were 14, 18, 10, 80, 6 and 8 SSLNs in No. 4, No. 5, No. 6, No. 7, No. 8 and No. 9 group lymph nodes respectively. And there were 10, 18, 8, 62, 2 and 4 SSLNs were demonstrated existing metastasis with a positive rate of 71.4%, 100%, 80.0%, 77.5%, 33.3% and 50.0% in No. 4, No~ 5, No. 6, No. 7, No. 8 and No. 9 group lymph nodes respectively. However, there were no significant correlations between the tumor＇s size and the positive rate of SSLN as well as the degree of tumor＇s differentiation and the positive rate of SSLN. Conclusion： The technique of SSLN tracing expands the application range of sentinel lymph node （SLN） tracing and provides a new thinking for researching of SLN in AGC.