ERBB2 and metastatic neoplasm: These findings were also confirmed by the results of a subset analysis of brain metastases in a large meta-analysis, which explored the receptor discordance between the primary lesions and metastatic tumors, and the conversion rates of ER, PR, and HER-2 between the primary lesions and brain metastatic lesions were 20.8, 23.3, and 12.5%, respectively (11).