ERBB2 and ductal breast carcinoma in situ: When the comparison was performed among PMBC, MBC+DCIS+IDC, MBC+IDC and MBC+IMPC, significant differences were identified in lymph node metastasis (p = 0.023), Her2 positivity (p = 0.014), high Ki-67 index (p = 0.008), chemotherapy (p = 0.011) and anti-Her2 targeted therapy (p = 0.002) (Table 2).