The 70-gene profile MammaPrint was established as a powerful predictor of disease outcome in breast cancer. The St Gallen 2009 recommendations include gene-expression signatures as an indicator for adjuvant therapy. Here we determined in an international cohort how MammaPrint could assist in patient management. Fresh tumor samples (n = 877) from breast cancer patients (T1–4N0–1M0) were collected from 23 hospitals in Europe, 2 in New Zealand and 1 in Japan between 2007 and 2010 by core needle biopsy or from a surgical specimen (study protocol MP090). We assessed agreement between the treatment advice as recommended by the 2009 St Gallen Highlights and classification according to MammaPrint.For the majority (93%) of these 877 breast cancer patients from international hospitals the St Gallen 2009 either recommends or suggests considering treatment with cytotoxic adjuvant therapy for whom MammaPrint indicates a low risk of recurrence in 38% of cases.
