The median length of time between a patient’s initial BC diagnosis to craniotomy of the sequenced BrM was 43.35 months and varied by inferred intrinsic subtype (p = 0.042; LumA (n = 10) subtype 40.15 months, LumB (n = 6) 77.50 months, HER2-Enr (n = 12) 35.50 months, Basal (n = 9) 46.60 months, and Normal (n = 2) 111.0 months (Fig. 6a). Here, ERBB2 is linked to breast cancer.