ERBB2 and metastasis: Brain metastasis (HER2−/HoR+ vs HER2+/HoR− vs HER2+/HoR+ vs HER2−/HoR−: 1.2% vs 3.4% vs 1.6% vs 5.1%, respectively) and lung metastasis (HER2−/HoR+ vs HER2+/HoR− vs HER2+/HoR+ vs HER2−/HoR−: 11.0% vs 28.1% vs 17.1% vs 33.1%, respectively) were more likely to occur in women with a HER2−/HoR− status.