In line with this, a poorer outcome has been observed in African and African-American patients (Wojcik et al, 1998; Ikpatt et al, 2002) when compared with breast cancers among Caucasians, with differences in the spectrum of tumour characteristics and prognostic features such as the presence of tumour necrosis, low ER positivity rate, high HER2-positive rate, and a high frequency of basal-like features (Mbonde et al, 2001; Ikpatt et al, 2002; Carey et al, 2006; Nalwoga et al, 2006, 2007; Morris et al, 2007; Bird et al, 2008). This evidence concerns the gene ERBB2 and breast cancer.