During the last decades, systemic treatment methods have evolved extensively, leading to improved survival22,23 and better locoregional control.22–26 The overview of the Early Breast Cancer Trialists’ Collaborative Group (EBCTCG) illustrated that treatment with tamoxifen diminished the LR rates by nearly 50% compared with placebo,23 and the use of aromatase inhibitors decreased the LR rates even further.27 Treatment with cytotoxic CT and targeted therapy improved locoregional control to an even greater extent.28–31. The gene discussed is CYP19A1; the disease is breast cancer.