Breast tumors growth is regulated by female sex steroid hormones. The level of the estrogen and progesterone receptors (ER and PR) expression by the malignant cells is important for the evaluation of the tumor prognostic and the benefit of a hormonal therapy. The aim of our study was to identify the expression of estrogen and progesterone receptors in primary breast tumors and in the corresponding axillary lymph nodes metastases, in 24 cases. The results showed that more than 30% of poorly differentiated breast carcinomas lost their expression of hormone receptors from the primary tumors to axillary metastases, an event which can be associated with an aggressive tumoral behaviour and resistance to hormonal therapy.