Fig. 3

Examples of various immunohistochemical stainings of breast primary tumor and corresponding metastases. These samples were from the same patient, variant ER expression was seen in the primary tumor cores (a, b, c, d and e), different ER expression was also found in the corresponding metastatic sites (f, g, h, i and j). This case shows various ER expressions among different tissue cores from the same primary lesion and every individual metastatic lymph node