They found that patients with luminal A and B like breast cancer had a small benefit from radiotherapy in addition to endocrine treatment (luminal A: HR = 0.4, p = 0.11; luminal B HR = 0.51, p = 0.18), whereas patients with Her2-positive and triple negative disease had a larger advantage from radiotherapy in terms of locoregional relapse (HER2-positive/“triple negative”: HR = 0.13, p = 0.0015). Here, ERBB2 is linked to breast carcinoma.