MKI67 and breast carcinoma: In this work, we used the simplified classification of luminal breast carcinoma to define luminal A tumors that displays high level of ER and PR expression and low expression of proliferation (Ki67 <14%) and growth factor receptor, and luminal B tumors that displays low level of ER and PR expression or PR absent and higher expression of proliferation (Ki67≥14%) and growth factor receptor [25].