The MammaPrint® test (https://agendia.com, by Agendia Inc.)examines the 70 most significant genes linked to recurrence of BC, while EndoPredict (https://endopredict.eu/, by Myriad Genetics GmbH) is an RNA-based multigene test that predicts the likelihood of distant recurrence in patients receiving adjuvant endocrine therapy for ER + and HER2 breast cancer. This evidence concerns the gene ESR1 and breast cancer.