ERBB2 and metastatic malignant neoplasm in the lymph nodes: The proportion of IMPC-B cases with histological grade III accounted for 33.2%, which was significantly higher than that of IDC-B (15%); the rate of lymph node metastasis was higher than IDC-B (43.5% vs. 30.9%), which is consistent with previous studies [6, 14]; IMPC-B is more common in HR+/HER2-, which is consistent with previous reports [15], and this study found that HER2-positive rate of IMPC-B patients was higher than that of IDC-B, 19.6% vs. 9.0%, and HR+/HER2+ were more common.