Many studies have aimed to identify an immunohistochemical profile that can act as a surrogate for gene array analysis (Makretsov et al, 2004; Nielsen et al, 2004; Matos et al, 2005), and it appears that a five-marker panel of oestrogen receptor (ER), progesterone receptor (PR), Her2, CK5/6 and EGFR shows promise in its ability to categorise invasive cancers to their molecular subtype (Cheang et al, 2008). Here, PGR is linked to cancer.