For example, evaluation of gene expression patterns of 176 candidate genes between primary tumors without lymph node metastasis and those with 10 or more positive lymph nodes revealed differences in gene expression, with significantly higher expression of ERBB2 (P < .0001) in tumors from node-positive compared to node-negative tumors [18]. This evidence concerns the gene ERBB2 and metastatic malignant neoplasm in the lymph nodes.