TP53 mutations were, unsurprisingly, common across cancer types (71.7% overall across ERBB2alt tumors among the five major ERBB2mut tumor types) but co-occurred more frequently with ERBB2 amplification than with ERBB2 mutation (66.2%–91.4% vs. 31.2%–65.6%, respectively). Here, ERBB2 is linked to cancer.