TP53 mutations in exons 4 to 11 have been reported in 10 % to 37 % of pure DCIS cases [44, 54, 75–79] and 20 % to 33 % of mixed DCIS cases [78, 79] and associated with high nuclear grade [54, 77] and HER2 subtype [54]. Here, ERBB2 is linked to ductal breast carcinoma in situ.