OS according to tumor subtype showed that patients with brain metastases from triple negative breast cancer experienced the shortest survival (median OS: 5 months; 95% CI: 4—not estimable), whereas patients with HR-positive and HER2-positive presented a median OS of 6 months (95% CI 2—not estimable) and those with HR-positive/HER2-negative had a median OS of 13 months (95% CI: 3–46 months; p = 0.19). Here, ERBB2 is linked to neoplasm.