Abstract
Sentinel lymph node biopsy (SNB) can be false negative in some cases. In our institution, SNB has been performed by injecting a combination of a radioactive tracer (RI) and a blue dye since April 2010 and a total of 235 patients underwent the combination biopsy procedure until April 2012. Of these 235 patients, there were three patients whose positive (hot and blue) lymph nodes (LN) on the combination RI and blue dye biopsy did not contain cancer cells, but negative LNs on the both RI and blue dye biopsies had metastasis. In all three patients, no metastases were identified in the hot and blue LNs but only nearby LNs contained cancer cells. True false negative cases are reported to include LN metastasis cases in which LNs are replaced with cancer except for skip metastasis. In these three cases, the metastatic LNs were also replaced with cancer. It is suggested for such cases that true sentinel lymph node can be negative on both the dye and RI biopsies and that blue dye and RI can be seen in the nearby LNs. We should avoid gaining false negative results for macrometastasis. A further decrease in the incidence of false negative results would contribute to more correct diagnosis and treatment.
