G. Söderqvist

Mammographic breast density during hormone replacement therapy: effects of continuous combination, unopposed transdermal and low-potency estrogen regimens.

Objective: The aim of this study was to evaluate the impact of different hormone replacement therapy (HRT) regimens on mammographic breast density. Study design: Mammographic density was recorded in women participating in a population-based screening program. At first mammogram, all women were non-users of HRT, and thereafter reported continuous use of the same HRT regimen. The study population comprised 158 women: a total of 52 women were using continuous combined HRT (conjugated equine estrogen 0.625 mg plus medroxyprogesterone acetate 5 mg); 51 women were using low-dose oral estrogen alone (estriol 2 mg daily); and 55 women were using unopposed transdermal estrogen given as a patch (estradiol 50 μg/24 h). Films were coded and analyzed for mammographic density by an independent radiologist blinded to treatments. Mammographic density was classified according to Wolfe. Results: An increase in mammographic density was much more common among women taking continuous combined HRT (40%) than for those using oral low-dose estrogen (6%) and transdermal (2%) treatment. The increase in density was already apparent at the first visit after starting HRT. During long-term follow-up, there was very little change in mammographic status. Conclusion: HRT regimens were shown to have different effects on the normal breast. There is an urgent need to clarify the biological nature and significance of a change in mammographic density during treatment and, in particular, its relation to symptoms and breast cancer risk.

Breast Cell Proliferation in Postmenopausal Women During HRT Evaluated Through Fine Needle Aspiration Cytology

The basis of breast cancer risk associated with hormonal therapies may lie in the regulation of cell proliferation. In a prospective, double-blind, randomized study postmenopausal women were given continuous combined hormone replacement therapy (HRT) either as estradiol valerate 2 mg/dienogest 2 mg, (E2V/DNG) or estradiol 2 mg/noretisterone acetate 1 mg (E2/NETA) for 6 months. Fine needle aspiration (FNA) biopsies were used for immunocytochemical analysis of breast cell proliferation before and during treatment. From 45 women completing the study 135 biopsies were obtained. In the total material there was a more than 4-fold increase in proliferation between baseline and 3 months (p < 0.001). The mean percentage of MIB-1 positive breast cells increased from 2.2 to 9.1%. In some individual women values were as high as 25%. No further increase was recorded at 6 months. While numerical values were somewhat lower in the E2V/DNG group, there were no significant differences between treatments. There was a positive correlation between breast cell proliferation (MIB-1%) and circulating levels of both estradiol (rs = 0.54, p < 0.01) and estrone (rs = 0.53, p < 0.01) after 3 and 6 months of treatment. No correlations with other endogenous hormones, proteins or with the two exogenous progestogens dienogest and norethisterone were observed. Increased breast cell proliferation should probably be regarded as an unwanted side-effect during HRT. Means to identify those women with the most pronounced proliferative response should be developed. The FNA biopsy technique may be a useful tool to monitor and evaluate the proliferative response to HRT in the normal breasts of postmenopausal women.

A comparative study of breast cell proliferation during hormone replacement therapy : effects of tibolon and continuous combined estrogen-progestogen treatment

Objectiveu2003To use the fine-needle aspiration (FNA) biopsy technique to compare the effects of tibolone, conventional hormone replacement therapy (HRT) and placebo on breast cell proliferation in postmenopausal women. Methodsu2003A total of 91 women were randomized to receive either estradiol 2u200amg plus norethisterone acetate 1u200amg (E2/NETA), tibolone 2.5u200amg or placebo for 6 months in a prospective double-blind trial. Breast cell proliferation was assessed using the Ki-67/MIB-1 monoclonal antibody. Resultsu2003From the 83 women who completed the study, a total of 166 FNA biopsies were obtained, and 118 of these aspirates (71%) were evaluable for MIB-1 content. Women with assessable biopsies were younger, had a lower body mass index, and had higher levels of sex hormone binding globulin and insulin-like growth factor-I than women in whom the cell yield was insufficient. During treatment with E2/NETA, there was an increase in proliferation (percentage of MIB-1) from a mean value of 2.2 to 6.4% after 6 months (pu2009<u20090.01). No significant changes were recorded during treatment with tibolone or placebo. There was a negative association between proliferation and serum levels of total (rsu2009=u2009−0.29, pu2009<u20090.05) and free (rsu2009=u2009−0.31, pu2009<u20090.03) testosterone. Conclusionsu2003Tibolone seems to have little influence on breast cell proliferation.

Breast epithelial proliferation in postmenopausal women evaluated through fine-needle-aspiration cytology

Objective: The aim was to evaluate fine-needle-aspiration (FNA) cytology as a method of following breast epithelial proliferation in postmenopausal women during hormone replacement therapy (HRT). Methods: Twelve healthy postmenopausal women were recruited and randomized to two different types of sequential HRT during 4 months of treatment. The women were administered continuous estradiol 50 μg/24 h with the addition of progestogen sequentially in the form of either vaginal progesterone gel 8 mg every 2nd day or medroxyprogesterone acetate 5 mg/day orally during 12 days per month for the complete treatment period. Fine-needle-aspiration biopsies were performed twice during the estrogen phases and twice during the estrogen plus progestogen phases of treatment. Breast epithelial proliferation was analyzed in these samples by immunocytochemistry to measure the content of the nuclear antigen Ki-67/MIB-1, which is expressed in proliferating cells. Results: From the 12 women, a total number of 47 FNA biopsies were taken. Thirty-eight of these aspirates, 19 from each of the estrogen and the estrogen plus progestogen phases, were evaluable for MIB-1 content (81%). There was a nonsignificant increase in levels of proliferation during the combined estrogen-progestogen phase (2.1%) compared with the estrogen-only phase (1.4%). These values were similar to those previously observed during the menstrual cycle in young fertile women. Conclusions: We conclude that the FNA biopsy technique is feasible for studying proliferation not only in young, normally cycling women but also in the postmenopausal breast.

Associations between serum testosterone levels, cell proliferation and progesterone receptor content in normal and malignant breast tissue in postmenopausal women

Progestogens and progesterone receptors (PR) may play an important role in increased breast proliferation following combined estrogen/progestogen hormone therapy, while androgens may counteract this effect. In 50 untreated healthy postmenopausal women and 48 untreated postmenopausal breast cancer patients, we measured serum levels of testosterone (T), sex hormone-binding globulin (SHBG), estrone (E1) and adrenal androgens; and additionally, in the breast cancer patients, cortisol and corticosteroid-binding globulin and endocrine data related to breast proliferation (assessed using the Ki-67/MIB-1 monoclonal antibody) and PR levels (determined by enzyme immunoassay) in the breast cancer tissue. In the healthy women the percentage of MIB-1+ cells showed significant negative correlations with serum levels of total T, calculated free T (fT) and the fT/E1 ratio; while in the breast cancer patients PR content showed significant negative correlations with fT level, the fT/E1 ratio and the T/SHBG ratio. No other correlations were found in any of the groups. Our findings in healthy women confirm previous reports of an antiproliferative effect of androgens in breast tissue and our finding in breast cancer patients suggests that this antiproliferative effect may be mediated via downregulation of PR.

p53 expression in breast and endometrium during estrogen and tamoxifen treatment of surgically postmenopausal cynomolgus macaques

Estrogens are important for both normal cell growth and malignant proliferation in the mammary gland as well as in the endometrium. Tamoxifen is a non‐steroidal anti‐estrogen widely used in breast cancer treatment. In recent years reports have been made of an increased risk of endometrial carcinoma during tamoxifen treatment. We used surgically menopausal cynomolgus macaques to study proliferation and p53 expression during hormonal replacement therapy (HRT) and tamoxifen treatment. Animals were treated continuously for 35 months with either conjugated equine estrogens (CEE; n = 20); medroxyprogesterone acetate (MPA; n =17); the combination of CEE + MPA (n = 13) or tamoxifen (n = 17) for 35 months. We found an increased expression of p53 in normal breast and endometrial tissue linked to CEE but not tamoxifen treatment. In the breast alveoli there was an association between proliferation measured by morphometry and p53 expression in all groups. However, in the endometrium CEE induced significantly more p53 positivity than tamoxifen, 9/20 vs. 3/17 in glands and 9/19 vs. 0/17 in stroma, respectively. If indeed long‐term treatment with tamoxifen as in the present study could inactivate the tumor‐suppressive function of p53, endometrial cells might thereby become more susceptible to genetic lesions associated with carcinogenesis.

Hormonal regulation of the normal breast

The breast is a target organ for reproductive hormones but basic knowledge on hormonal effects is very poor. Available data indicate that the breast is regulated in a specific manner which is distinct from the endometrium and other target organs. It seems clear that the breast undergoes cyclic changes during the menstrual cycle and that in vivo there is a direct stimulatory action of progestogens on the breast. In surgically postmenopausal female macaques continuous combined estrogen/progestogen therapy was found to induce greater proliferation than estrogen alone.

Estrone - a partial estradiol antagonist in the normal breast.

Abstract Oral hormone replacement therapy (HRT) based on estradiol-17β (E2) greatly increases circulating estrone (E1) levels. E1 is an estrogen receptor agonist but may also be a partial E2 antagonist. We investigated the effects of circulating E1 on the association between circulating E2 and the increase in mammographic density (∂MD) in 46 healthy post-menopausal women treated with E2 2u2009mg and norethisterone acetate 1u2009mg daily. MD and serum E1 and E2 were measured before and after 6 months of treatment. At high E1 levels, ∂MD showed significant positive correlations leading to increase (∂-values) in both E1 and E2. Lowering the upper serum E1 limit strengthened the correlations to ∂E2 while the significant correlations to ∂E1 disappeared. E1 at high concentrations may act as a partial E2 antagonist also in the normal breast in vivo and disturb relationships between circulating E2 and biological estrogen effects. When investigating the relations between circulating steroids and their effects, structurally related compounds, which may act as partial antagonists, have to be considered, at least when they are present in higher concentrations. Chinese abstract 口服激素替代治疗（HRT）基于17β-雌二醇（E2）大大增加了循环的雌酮（E1）的水平。E1是一种雌激素受体激动剂，但也可能是一个E2的部分拮抗剂。我们研究了46名健康绝经后女性每天口服E2 2mg和醋酸炔诺酮1mg后循环中E1在循环中E2与乳腺密度增加之间关系中的作用。治疗前和治疗6个月后分别测定乳腺密度及血清E1和E2。E1高水平时，乳腺密度与E1和E2的增加呈密切正相关。不断降低血清E1至上限，与E2的相关性加强而与E1的相关性消失。E1在高浓度时可能是体内正常乳腺组织内E2的部分拮抗剂，干扰了循环中E2和雌激素生物效应之间的联系。当研究循环中类固醇和它们作用的时候，结构相关的化合物具有较高浓度的时候必须要考虑，因为它们可能是部分拮抗剂。

So similar and so different: Circulating androgens and androgen origin in bulimic women

Hyper androgen state frequently can be diagnosed in bulimic women. Eating disorder not otherwise specified (EDNOS) recognized as a less severe form of bulimia nervosa (BN). The objective of the study was to determine whether androgen levels and androgen origin differs in bulimic women compared to control subjects. Forty-six women with bulimia nervosa (BN), 31 with eating disorder not otherwise specified, purging type (EDNOS P) and 56 matched healthy controls were studied with respect to serum testosterone (T), 5alpha-dihydrotestosterone (DHT), sex hormone-binding globulin (SHBG), deyhydroepiahndrosterone sulfate (DHEAS) and luteinizing hormone (LH) and to ovarian morphology. Despite all groups had almost identical androgen and SHBG levels; there were differences in the origin of circulating T and DHT. Correlation analysis suggest major differences in the formation of circulating testosterone (T) and 5α-dihydrotestosterone (DHT) with BN being more like the control subjects with peripheral formation from 4-androsterne-3,17-dione (A-4), dehydroepiandrosterone sulfate (DHEAS) and also from T. While in EDNOS group a possible direct ovarian T secretion and a DHEAS modulating action of androgens on pituitary gonadotropin secretion is present. The origin of circulating T and DHT differs between bulimics. Our findings do probably not reflect direct actions of circulating DHT on pituitary LH secretion in the women with EDNOS, but rather the effect of A-4, T via conversion to DHT in the central nervous system, indicating psych/endocrine differences between the two groups of bulimic women.