The hypothesis on cancer stem cells assumes the existence of small subpopulation of cells that possess the ability to undergo self-renewal and can give rise to the diversity of differentiated cells that form the tumour. It has been accepted that CD44(+)/CD24(-/low) phenotype is one of the features characterizing breast cancer stem cells. The aim of our study was to assess (1) prognostic significance of CD44/CD24 expression as well as (2) a relation between the above-mentioned phenotype and breast cancer subtypes [based on estrogen (ER), progesterone receptors, human epidermal growth factor receptor 2 and Ki67 status] and expression of selected markers such as fascin, laminin-5 gamma-2 chain, cytokeratin (CK) 5/6 and 8/18, epidermal growth factor receptor (EGFR), smooth muscle actin, P-cadherin and lymphocytic infiltration in invasive ductal breast cancer patients (T ≥ 1, N ≥ 1, M0), who underwent mastectomy followed by chemotherapy (with taxanes and/or anthracyclines) or/and hormonotherapy. We noted that most cancers with CD44-/CD24- and CD44-/CD24+ phenotype were ER positive. The majority of CD44-/CD24-, CD44-/CD24+ and CD44+/CD24- tumours were characterized by CK5/6 and EGFR negativity. In univariate analysis we demonstrated that patients with pN1/pN2 and with CD44 +/CD24- carcinomas had significantly lower risk of progression or cancer-related death than those with pN3 or tumours characterised by other CD44/CD24 expression patterns. We also found 100 % DFS in 12 patients with CD44+/CD24-/CK5/6+/ER- phenotype. Other analysed parameters were insignificant. We conclude that tumours with immunophenotypes: CD44+/CD24- and CD44+/CD24-/CK5/6+/ER- might be more sensitive for chemotherapy based on taxanes and/or anthracyclines.