ESR1 and breast cancer: Retrospective analyses from randomized trials have suggested that the recurrence score of a 21 gene assay [28,29] could identify a subset of ER + /HER-2 negative BC patients with positive nodes who did not derive a significant benefit from chemotherapy: Albain et al. [30] and Dowsett et al. [31] found low risks of distant metastases in luminal low recurrence score N+ disease and luminal low recurrence score disease with 1 to 3 nodes involved respectively.