High HER2 concordance between primary tumors and recurrent or metastatic tumor has been shown in many studies.[13,14] In this study, the positive expression rate of HER2 in primary breast cancer was 19.8%, the positive expression rate in recurrent and metastatic breast cancer was 23.8%, and the expression discordance rate was 10.6% (11/104). This evidence concerns the gene ERBB2 and breast cancer.