The nodal tissue removed is examined and the individual lymph nodes are separated. One node, the sentinel node, should be quite hot, while its neighbors are much less so (Figure 10). In the example shown, lymph node A is labeled as the principal sentinel lymph node. Lymph node B is labeled as a sentinel node. Node C is not a sentinel node, as its counts are less than 10 percent of the principle sentinel node and it is not blue.