ERBB2 and ductal breast carcinoma in situ: Contrary to in the breast cancer alone groups, in the breast cancer with PD groups, the HR status (P = 0.182 in PD‐IDC and P = 0.371 in PD‐DCIS), HER2 status (P = 0.788 in PD‐IDC and P = 0.643 in PD‐DCIS), and combined molecular subtype (P = 0.196 in PD‐IDC and P = 0.853 in PD‐DCIS) were not found to affect disease prognosis.