ERBB2 and breast cancer: In order to verify the composition of metastatic breast cancer, we have added some known breast markers which include estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor-2 (HER-2), GATA-binding protein 3 (GATA-3), Mammaglobin A, gross cystic disease fluid protein 15 (GCDFP15) and E-cadherin.