Steroid Receptor Determinations in Mammary Carcinoma in Women

Abstract

It is now accepted that the determination of specific steroid-binding proteins in mammary carcinoma tissue allows a forecast of the success of endocrine therapy (Jensen et al., 1971; Savlov et al., 1974; Maass et al., 1975). The content of receptor protein varies and depends on the tumour tissue itself, e.g., primary tumour or metastases, on the endocrinological condition of the woman, and finally on the method of determination. It is important for the clinician to know whether the mammary carcinoma has definite steroid-binding proteins, especially oestradiol receptors (ER), or not. The limit of analytical detection is about 3 fmol/mg cytosol protein. We describe carcinomata as ER-positive if more than 5 fmol oestradiol/mg cytosol protein is bound. In the endocrine treatment of mammary carcinoma, it is striking that ER-positive tumours have shown remission in only about 60% of the cases. It seems therefore that the determination of the ER alone is not sufficient as a marker. In the search for other markers it has been shown that the determination of progesterone receptors (PR) in addition to ERs allows a more accurate statement on the hormone dependence of the tumour.