ESTROGEN AND PROGESTOGEN CYTOSOL RECEPTORS IN HUMAN BREAST CARCINOMA

Abstract

The authors have studied Estrogen (RE) and Progestin (RP) cytosol receptors in 379 human breast carcinomas: 281 tumors suitable for surgery, 26 pseudo‐inflammatory tumors, 52 metastases and 20 recurrences. They have used an exchange technique with estradiol for RE and a synthetic compound, R 5020, for RP. The results point out that high rates of RE correlate with post‐menopausal women and high rates of RP with pre‐menopausal women. Tumours are considered receptor‐positive when the binding sites concentration exceeds 100 fmoles/g tissue. Using this as a base 32% of the tumors are RE and RP negative. Considering only the positive tumors, 54% contain both receptors, 31% only RE and 15% only RP. The percentages are also given in terms of the hormonal state of the patients. The results are discussed in terms of Mc Guire's hypothesis that both receptors are necessary to obtain a positive response to hormonal therapy. Correlation between histology and receptors is also discussed.