Multi-institutional HER2 testing was performed on 5,305 diverse cancers including non–small-cell lung (n = 1,175), breast (n = 1,040), and colon cancers (n = 566; N = 3,926 tested for CNV; N = 1,848, mRNA; N = 2,533, IHC). This evidence concerns the gene ERBB2 and malignant colon neoplasm.