This uses a combination of ER, HER2, CK5 and EGFR to generate four groups, which in this study gives a frequency of basal-like cancers in this cohort similar to that described earlier (van de Rijn et al, 2002; Abd El-Rehim et al, 2004; Nielsen et al, 2004; Matos et al, 2005). Here, EGFR is linked to cancer.