Differentiated expression of estrogen receptors (ER) and progesterone receptors (PgR) in ductal breast cancers.

Contents of estrogen receptors (ER) and progesterone receptors (PgR) in cells of breast cancers represent strong predictive factors. The higher is the contents of ER and PgR in breast cancer, the higher is a probability of obtaining a response to hormonal therapy and prognosis for the patient is better. In a routine manner, all tumours of mammary gland are subjected to evaluation of ER and PgR expression using immunohistochemistry. Forty ductal breast cancers (pT2N0) were subjected to an immunohistochemical evaluation (IHC) aimed at detection of ER and PgR expression. From every tumour three samples were taken for immunohistochemical studies: the lateral one from the side of axilla (ER-1; PgR-1); the median one (ER-2; PgR-2) and the medial one from the side of sternum (ER-3; PgR-3). The levels of both ER and PgR expression proved to be highly differentiated between the medial zone of the tumour and its periphery. The distinct expression of ER and PgR in ductal breast cancers, dependent on evaluated zone of the tumour, confirms its heterogeneous character and exerts an effect on the type of applied treatment.