In fact, 47% of pT1a pN0 HER2-positive breast cancer patients (46 out of 97 patients with pT1a tumors) received adjuvant systemic therapy with trastuzumab, because other bio-pathological and clinical characteristics had an impact on the treatment choice, such as proliferation index, age, and hormone receptor status. This evidence concerns the gene NR4A1 and breast carcinoma.