PAX8 and breast neoplasm: Therefore, the size of the lump on imaging is smaller than those on physical examination while the metastatic lesions are usually consistent with clinical imaging.[41] Immunohistochemical markers are also significant and the combined use of multiple markers can provide more sufficient diagnostic evidence.[3] WT-1, PAX-8, and GCDFP-15 play a major role in differentiation between primary breast tumors and breast metastasis from ovarian tumors.