Following the results of four major adjuvant trials (NCCTG N9831, NSABP B-31, HERA and BCIRG-006),1, 2, 3 administration of adjuvant trastuzumab for 1 year concurrently to chemotherapy became the standard of care for patients with HER2-positive early breast cancer (eBC). This evidence concerns the gene ERBB2 and breast carcinoma.