In the case of complementary therapy, radiation therapy was more likely to be performed in patients with B-HER2 negative luminal breast cancer, in divergence from Cintra et al.,5in which radiotherapy was more related to luminal subtype A. In this sense, Pires et al.21reported that radiation therapy has locoregional control of the disease as its main indication and its use is more common in the postoperative period to decrease the chances of recurrence; however, in some cases, it is used preoperatively to reduce tumor volume. The gene discussed is ERBB2; the disease is breast carcinoma.