ERBB2 and breast cancer: Treatment strategies for this type of breast cancer are limited, due to the lack of hormone receptor expression (oestrogen receptors and progesterone receptors) and the absence of amplification for the gene coding for the Human Epidermal Growth Factor Receptor 2 (HER2) protein, in tumor cells.[1] As a result, patients diagnosed with TNBC cannot benefit from endocrine therapy or anti-HER2 therapy.