PGR and neoplasm: Since BrC is a very heterogeneous disease with well-defined morphologies, molecular attributes, prognoses, and treatment options, clinical decisions are mainly made on the basis of the tumour stage, lymph-node status, and the expression of molecular determinants, represented clinically by oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and the proliferation marker Ki67 [8].