Clinical Value Of Sentinel Lymph Node Biopsy Combined With Surrounding Lymph Node Sampling In Reducing False Negative Rate In Breast Cancer

Objective The birth of sentinel lymph node biopsy(SLNB) technology is a milestone in the development of breast cancer surgery, it becomes an important part of the standard treatment of clinical early breast cancer. However, the problem of false-negative in a certain extent hinders the SLNB in clinical promotion. In the domestic and international study, the false-negative rate of SLNB was about 10%. The American Society of Breast Surgeons established a task force to suggest acceptable standards in SLNB. These recommendations are that the identification rate for SLNB was 85% or higher, and that a false-negative rate was 5% or less.This study aimed to explore the meaning of samplingperipheral surrounding tissue of sentinel lymph nodes(SLN) to reducefalse negative rate of SLNB and the phenomenon of ‘skip metastasis' on the influence of false negative rate of SLNB.Methods A total of 596 patients were examined using radiocolloid combined with blue dye tracer SLNs at Shandong Cancer Hospital and Institute from March 1, 2012 to June 30, 2015. The entry conditions included(1) breast cancer was confirmed by fine needle aspiration or biopsy;(2) preoperative clinical examination and imaging examination were confirmed as c N0 patients;(3) no anti-cancer therapy was offered before surgery;(4) after the SLNs and peripheral lymph node were resected, whether or not there was a metastasis, patients underwent Level I combined with Level II lymph node dissection or complete axillary lymph node dissection(Level I, II, III).Remove the SLNs first, and then remove suspicious lymph nodes in SLNs around5 cm diameter range detected under the condition of without destroying peripheral vascular and nerves, axillary lymph node dissection or Level?and? dissection last.The SLNs, suspicious lymph nodes and the rest of axillary lymph nodes detected into three groups sent to pathological examination, Analysis the correlation of metastasis in this three groups.Results The identification rate of 596 patients was 95.1%(567/596),the metastasis rate of axillary lymph nodes was 33.7%(191/567),the false negative rate of SLNB was 9.9%(19/191),11 cases in 19 False negative patients were detected metastasis lymph nodes from surrounding tissues, incorporating SLNs and suspicious lymph nodes together, the false negative rate was 4.2%(8/191), The rate of decline showed a significant difference(P = 0.028). The patients were divided into 4 groups of n=1,2,3 and ?4 according to the number of detected SLNs. The false negative rate was19.6%?9.8%?7.3% and 2.3% respectively, The difference is statistically significant(P= 0.049). After suspicious lymph nodes clearing, The false negative rate of decline for n?3 group showed a significant difference(12.2% VS. 4.7%;P=0.021), and n?4 group has no statistical significance(P = 1.000). In this study, the ‘skip metastasis' rate was2.52%(15/596),the false negative rate which‘skip metastasis' caused was 2.09%.Conclusions False negative rate of SLNB is related to the number of detected SLNs,with an increased number of SLNs, the false-negative rate of SLNB decreased.Expanding dissection surrounding tissue of SLNs can make the false negative rate of SLNB reduced to less than 5% of the acceptable Level for the patients who detected no more than 3 SLNs. For the patients with ? 4 detected SLNs, we believe SLNB can predict the state of axillary lymph nodes, and it is not necessary to carry out peripheral lymph node sampling. Due to the existence of ‘skip metastasis' and the phenomenon of ‘individualized metastasis', the false negative rate of SLNB could not disappear entirely.