ERBB2 and ductal breast carcinoma in situ: Several studies have evaluated the prognostic significance of biomarkers including oestrogen receptor (ER) expression, progesterone receptor (PR) expression and HER2/neu expression as predictors in DCIS but most of these studies were limited due to the number of patients included, variations in treatment and short follow-up (Ringberg et al, 2001; Provenzano et al, 2003; Cornfield et al, 2004).