Pooled analysis of prospective European studies assessing the impact of using the 21-gene Recurrence Score assay on clinical decision making in women with oestrogen receptor–positive, human epidermal growth factor receptor 2–negative early-stage breast cancer

PURPOSE: The 21-gene Recurrence Score assay (Oncotype DX) provides prognostic/predictive information in oestrogen receptor positive (ER+) early breast cancer, but access/reimbursement has been limited in most European countries in the absence of prospective outcome data. Recently, two large prospective studies and a real-life 5-year outcome study have been reported. We performed a pooled analysis of prospective European impact studies to generate robust data on impact of use in different clinical subgroups. METHODS: The analysis included four studies (French, German, Spanish, and British) in ER+ human epidermal growth factor receptor 2-negative breast cancer patients (n = 527). Node-positiv…