Endocrine therapy has long been employed as adjuvant therapy after surgery in those with oestrogen receptor (ER)- and/or progesterone receptor (PR)-positive tumours and is very effective in reducing recurrences and death (Early_Breast_Cancer_Trialists’_Collaborative_Group, 2001, 2005; Baum et al, 2002). This evidence concerns the gene PGR and neoplasm.