Estrogen and progesterone receptor status in breast cancer in Kuwait female population.

The levels cytosol estrogen (ERc) and progesterone (PRc) receptors were determined in 315 primary breast cancers of female Arab patients aged 23-80 years. Most of breast cancers (78%) occurred in women aged 21-50 years, and only 22% were in women aged 51-80 years. Breast cancers containing ERc and PRc concentrations in the range 5-50 fmol/mg of cytosol protein (mg c.p.) were found with similar frequency in women aged under or over 50 years (53% for ERc and 43% for PRc, respectively). On the other hand, breast cancers with ERc values of > 50 and > 100 fmol/mg c.p. were twice as frequent in women aged over 50 years as in women aged under 50 years. The frequency of breast cancers with PRc level of over 50 fmol/mg c.p. in women aged over 50 years was only half that in those aged under 50 years. In breast cancers of Kuwait Arab women the higher values of ERc (> 100 fmol/mg c.p.) and PRc (> 50 fmol/mg c.p.) were less frequent than in other populations reported in literature. The low frequency of breast cancer in postmenopausal Kuwait women is associated with low proportions of tumors with higher ERc and PRc contents. In contrast to this, data from literature indicate that in the North Western European and American populations the postmenopausal incidence rise of breast cancers is associated with increased proportions of tumors with higher ERc and PRc levels.

Relations between epidermal growth factor receptor and oestrogen and progesterone receptors in breast cancers of premenopausal and postmenopausal patients in Kuwait.

The levels of cell membrane epidermal growth factor receptor EGFR and cytosol (c) and nuclear (n), oestrogen (E) and progesterone (P) receptors (R) were determined in 132 specimens of primary breast cancers. In the tumours of postmenopausal women an inverse significant correlation was demonstrated between the concentrations of EGFR vs. ERc, ERn, and PRc while no such correlation was noted in the tumours of premenopausal women. Premenopausal and postmenopausal EGFR positive tumours (> or = 10 fmol/mg membrane protein) could be regarded as homogenous with respect to the concentration of ER and PR whose mean values were low and without being significantly different. EGFR negative tumours were heterogeneous with respect to the ER and PR concentrations. Postmenopausal EGFR negative (< 10 fmol/mg membrane protein) tumours had evidently higher mean values of ER and PR than premenopausal EGFR negative tumours, but these differences were statistically significant for oestrogen receptors only. The levels of ER and PR of premenopausal EGFR negative tumours were approximated to the corresponding levels of EGFR positive tumours.

Estrogen receptor in human breast cancer in relation to tumor morphology and endocrine therapy.

The presence of estrogen receptors (ER) was determined in 111 human breast cancer specimens. In 61% of the tumors, specific estrogen binding was found and in 39% of the tumors ER was absent. In 69 tumors no correlation was found between the histological grading of the tumor and the level of ER. The values of ER in tumors from patients over 50 years of age were usually much higher than those for patients under 50 years of age. Different methods of endocrine therapy were applied in 20 patients. In 10 of 15 patients with ER positive tumors, endocrine therapy resulted in remission. Only 1 of 5 patients with ER negative tumors responded with remission. It is concluded that estimation of ER in tumor tissue is helpful in the selection of patients for endocrine therapy.

Estimation of high affinity estradiol binding sites in the human breast cancer.

The specific estrogen binding capacity of the cytosol has been investigated in 51 human breast cancers (49 women, 2 men). The estrogen binding sites of the cytosol has been analysed by Korenman's dextrancoated charcoal technique. Several methods have been used in order to distinguish the specific estrogen binding sites and the unspecific binding: temperature differentiation and saturation of the binding sites with nonlabelled estrogen or its antagonist Clomid. It has been concluded that the differentiation of the estradiol binding sites (specific or unspecific) with the elevated temperature effect or the additon of Clomid may be helpful only as a qualitative test. The elevated temperature of Clomid may influence the increase of the unspecific estradiol binding. The most suitable method to eliminate the unspecific binding of estradiol is the saturation of cytosol from control samples with non-radioactive estradiol-17-beta. The specific estrogen binding capacity of the cytosols of different tumours varied over a wide range (0--840 fM E2/mg protein). It has been found that among 51 persons there were 31 patients (61%) with measureable amounts of high affinity estradiol binding sites in cancerous tissues. In 20 cases (39%) the existence of estradiol specific binding sites could not be observed.