The same rationale would apply to women with HoR-positive, HER2-negative invasive breast cancer with 1–3 positive lymph nodes.6 Several prognostic factors, including clinical-pathological features such as age, tumour size, percentage of ER- and PR-positive cells as well as Ki67-index,7–9 predict the risk of recurrence and can help identify women who would benefit the most from chemotherapy. This evidence concerns the gene ERBB2 and invasive breast carcinoma.