HER2 positive breast carcinoma (MONDO_0006244) is a biologic subset of breast carcinoma defined by high expression of HER2, GRB7, and TRAP100, and by lack of expression of estrogen receptor (ER). Also known as: ERBB2 Overexpressing subtype of breast carcinoma, HER2 Overexpressing breast carcinoma, HER2 Overexpressing subtype of breast carcinoma, HER2 Positive breast cancer, Her2-receptor positive breast cancer.