Indeed, the latest evidence in BC adjuvant therapies concerns escalation targeted strategies addressed to high-risk patients, defined by lymph node-positive disease, residual disease after neoadjuvant therapy, higher Ki67, and/or selected using a composite score, such as the clinical and pathological stage (CPS) and estrogen-receptor status and histologic grade (EG) (CPS + EG scoring system), and the analysis of pathogenic mutated genes [81]. This evidence concerns the gene ESR1 and breast cancer.