Figure 2.

Negative Predictive Value vs. Number of Negative Lymph Nodes Sampled. Plot demonstrates the theoretical negative predictive value (NPV) for lymph node metastatic disease based upon the number of lymph nodes sampled, assuming each node sampled is negative for metastatic disease. The plot is based upon the equation presented in the text with the expectations that the average colonic resection contains a total of 90 lymph nodes and the average case of metastatic disease contains nine positive nodes. These expectations are based upon reference 39