In contrast, the 3 major dendrogram arms were primarily distinguished by their different proportions of ErbB2-positive cancers, with the first showing almost exclusively ErbB2-positive cancers (6/7), the second showing very few ErbB2-positive cancers (3/9), and the smallest and most heterogeneous of these arms showing only ErbB2-positive cancers (4/4). Here, ERBB2 is linked to cancer.