The relationship between mammographic density and duration of hormone therapy: effects of estrogen and estrogen-progestin

BACKGROUND: The purpose of this study was to examine the effects of duration of hormone therapy (HT) and treatment regimens on mammographic density. METHODS: A retrospective study was carried out of of 467 post-menopausal women who received estrogen or estrogen-progestin and had regular mammographic density determination by the Breast Imaging Reporting and Data System between 1994 and 2001. RESULTS: The fraction of women using HT who had an increase in mammographic density became more important over time. Further analysis of the effects of regimens after 4 years of HT shows that the increase in mean density was much greater in women receiving combined HT than in those receiving estrogen alone. The incidence of increased mammographic density showed significantly progressive increases over the duration of combined HT from 7.5 to 22.4%. CONCLUSIONS: Although most women using HT maintained breast density at pre-treatment levels, there is a note of caution for women using long-term HT, especially those using combined estrogen-progestin.     

Mammographic breast density changes after 1 year of tibolone use

Hormone replacement therapy (HRT) is widely used with a large variety of regimens and medications. For each of these regimens the goal is the same but there is always a fear about side effects, especially on breast. Mammographic screening is a standard tool for all women receiving hormone replacement therapy. Breast density is very important, because it interferes with the sensitivity of the evaluation and it is also a predictor of malignity. OBJECTIVE: We planned a study to investigate the effects of tibolone on mammographic breast density. DESIGN AND METHODS: We studied 70 postmenopausal women who started tibolone therapy (2.5 mg per day) after initial mammography and blood samples taken for biochemical examinations. None of the women used any hormone replacement therapy before. Eleven of them either discontinued the therapy or lost contact. After 1 year, we evaluated 59 women by mammographic status, using Wolfe classification. Mammographies were analyzed by two independent radiologists. RESULTS: Mammographies of 59 women were compared with the initial ones. While in the low density patterns, there was a slight increase (15%; P < 0.05); in the higher density groups, there was a decrease of 25% as observed by one radiologist, and 16% according to the other (P < 0.05). None of the women had a diffuse, high density pattern. There was no statistically significant inter-observer variation between two radiologists (P < 0.05). CONCLUSIONS: Wolfe classification allows easy interpretation of mammographic evaluation and the results are reproducible. Tibolone, as a tissue-specific steroid, does not have an estrogenic effect on breast cells. We found that it might limit, even reverse breast density increase, especially in postmenopausal women with high breast density.     

Effects of hormone therapy on estrogen synthesis from E1S in the mammary gland of postmenopausal women

OBJECTIVES: To investigate the effect of hormone therapy (HT) on the expression of hormone receptors and the ex vivo estrogen biosynthesis in the breast. METHODS: Comparative studies were carried out in breast tissue from 28 postmenopausal women undergoing breast surgery due to breast cancer (BC). Glandular breast tissue at least 1cm distant from the tumor was analyzed. Groups included patients having received HT (n=18), and non-user of HT (controls, n=10) prior to BC diagnosis. Steroid sulfatase (STS) activity was evaluated by incubating homogenized breast tissue with [3H]-estrone sulfate. Thin layer chromatography was performed to separate the products estrone (E1) and estradiol (E2). Histomorphometry for breast tissue composition and immunohistochemistry for expression of estrogen receptor (ER) alpha and beta as well as progesterone receptor (PR) were performed. RESULTS: In all groups, significantly more E2 than E1 was produced. Local E2 formation was higher in women having been treated with estrogen and progestogen (p< or =0.05). Local EZ formation was positively correlated with ER alpha expression (r(s)=0.5; p=0.03). Histomorphometrical and immunohistochemical outcomes did not differ between groups. However, the amount of vessels was higher in women having been treated with HT compared to controls (p=0.09). CONCLUSIONS: Long-term HT increases local estrogen formation in normal human breast tissue.     

Fibromatosis of the breast: age-correlated morphofunctional features of 33 cases

OBJECTIVE: To predict if antiestrogenic agents are useful in the treatment of breast fibromatoses, we undertook an immunohistochemical study of sex steroid hormone receptors (estrogen receptor, progesterone receptor, and androgen receptor) and protein pS2 in 33 cases. METHODS: The morphologic and immunohistochemical findings were correlated to patient menstrual status, which was categorized as childbearing age (n = 15), perimenopausal (n = 8), and postmenopausal (n = 10). RESULTS: Fibromatoses in women of childbearing age were more cellular, more mitotically active, and displayed a larger proportion of cells with mild atypia than those in perimenopausal and postmenopausal women. The hormonal status of these 3 groups does not explain the morphologic variations observed in these groups, inasmuch as no immunostaining for any of the hormone receptors was detected in the tumors. CONCLUSIONS: The absence of estrogen receptor and pS2 in breast fibromatoses suggests that antiestrogenic agents are unlikely to be beneficial in the management of these tumors. Assessment of the hormone receptor profile is a useful adjunct in the diagnosis of spindle cell lesions of the breast. Although most spindle cell carcinomas as well as fibromatoses of the breast do not express estrogen or progesterone receptors, the absence of androgen receptor reactivity would favor a diagnosis of fibromatosis over that of myofibroblastoma.     

Curcumin inhibits MPA-induced secretion of VEGF from T47-D human breast cancer cells

OBJECTIVE: Recent clinical trials show that women who receive combined estrogen and progestin hormone therapy (HT) have a higher risk of breast cancer than women who receive estrogen alone or placebo. We have shown that progestins stimulate expression of vascular endothelial growth factor (VEGF), a potent angiogenic factor, in human breast cancer cells that express the progesterone receptors and mutant p53 protein. Because increased levels of VEGF promote tumor progression, compounds that prevent progestin-induced expression of VEGF could be clinically useful. The objective of this study was to examine whether the polyphenol compound curcumin has the capacity to block progestin-induced secretion of VEGF from T47-D human breast cancer cells. DESIGN: The estrogen and progesterone receptor containing T47-D human breast cancer cells was exposed to 10 nM progesterone or synthetic progestins and varying concentrations of curcumin to determine whether curcumin blocks progestin-dependent production of VEGF from tumor cells. RESULTS: Curcumin (0.001-10 microM for 18 h) reduced medroxyprogesterone acetate (MPA)-induced secretion of VEGF from T47-D cells in a dose-dependent manner. Secretion of VEGF from cells treated with progesterone or progestins other than MPA was unaffected by curcumin. CONCLUSIONS: MPA is the most widely used progestin in HT. Curcumin may therefore provide a clinically useful tool for the suppression of MPA-induced elaboration of VEGF by tumor cells. We propose therefore that clinical trials to assess the beneficial effects of curcumin in postmenopausal women are warranted.     

Mammographic changes associated with raloxifene and tibolone therapy in postmenopausal women: a prospective study

OBJECTIVE: The prolonged use of estrogen therapy is associated with a slightly increased risk of breast cancer. Alternative therapies that are effective in the prevention of menopause, having associated morbidities but no unwanted effects, are of primary interest in the pharmacologic research. The aim of this study was to evaluate the effect of two alternative to estrogens drugs, the selective estrogen receptor modulator raloxifene and the tissue-specific tibolone, on the mammographic appearance of the breast. DESIGN: The study group comprised 131 postmenopausal women aged 41 to 67 years. The women were at least 2 years postmenopausal, free of climacteric symptoms, and at the time of entry to the study had not had therapy for at least 9 months. Women with risk factors for osteoporosis or cardiovascular disease were allocated either to tibolone (n = 56) or raloxifene (n = 48) therapy. Women with no risk factors and women who either did not qualify for or denied treatment (n = 27) served as controls. The study duration was 12 months. Women received a baseline mammogram before commencing therapy and a repeat mammogram at the end of the study period. Mammogram findings were classified according to the modified Wolfe criteria by two expert radiologists. RESULTS: No difference was identified between groups with respect to baseline characteristics associated with breast cancer risk. Similarly, no difference was detected between groups concerning the modified Wolfe classification of baseline mammographic findings. In the tibolone group, 10.7% of the women showed an increase in breast density in the 12-month reevaluation. The respective figure in the raloxifene group was 6.3%, whereas no woman in the control group showed an increase in breast density. Differences in the increase in breast density between groups did not, however, reach statistical significance. Accordingly, 10.7% of women in the tibolone group and 18.8% of women in the raloxifene group exhibited involutionary changes in the repeat mammogram, whereas 25.9% of women in the control group revealed a decrease in breast density in the 12-month examination. The percentages were not significantly different between groups. CONCLUSIONS: Breast density as shown by mammography was stable in a majority of patients and changed in a minority of cases for both tibolone and raloxifene. In most patients, these drugs are not likely to interfere with mammogram interpretation. Larger long-term studies are needed to confirm the impact of prolonged tibolone or raloxifene administration on mammography.     

Associations between mammographic density and body composition in Hispanic and non-Hispanic white women by menopause status

OBJECTIVE: To evaluate the associations of body composition, including percentage of lean and fat mass, with the percentage of mammographic density and mammographic dense area among pre- and postmenopausal Hispanic and non-Hispanic white women. DESIGN: In this cross-sectional study, a total of 238 women aged 41 to 50 or 56 to 70 years were recruited from local mammography clinics and community health centers. Postmenopausal status was defined as an absence of any menstrual cycle within the past 12 calendar months or having a follicle-stimulating hormone level between 22 and 138 mIU/mL. The participants' most recent mammograms were used for the mammographic density analysis. Body composition was measured by dual-energy x-ray absorptiometry. The associations between the percentage of mammographic density or mammographic dense area and body composition components were analyzed using logistic regression. RESULTS: Mammographic dense areas were similar in Hispanic and non-Hispanic white women. The percentage of mammographic density varied by ethnicity in premenopausal (P = 0.023), but not in postmenopausal women. Body composition, both higher lean mass and lower fat mass, was associated with a higher percentage of mammographic density (P < 0.05). Interestingly, a higher percentage of total body fat mass and a lower percentage of total body lean mass were correlated with larger breast dense areas in premenopausal women but with lower breast dense areas in postmenopausal women. These relationships between body composition and mammographic density measurements were not significantly affected by factors such as age, ethnicity, and body weight. CONCLUSIONS: Body composition is highly correlated with mammographic density and should be examined as a possible confounding factor in studies involving mammographic density measurements and breast cancer risk.     

Bone mineral density in breast cancer patients with positive estrogen receptor tumor status

AIM: The aim was to investigate bone mineral density (BMD) in breast cancer patients with positive estrogen receptor (ER) tumor status. METHODS: The participants were 110 postmenopausal breast cancer patients with positive estrogen receptor (ER+) tumor status. Two hundred and sixty-one age-matched, healthy postmenopausal women, all of whom were selected from our pooled data, served as controls. Age, age at menopause, years since menopause (YSM), height, weight, and body mass index (BMI, wt/ht(2)) were recorded. Lumbar spine (L2-4) BMD and Z-score were assessed by dual-energy X-ray absorptiometry. RESULTS: Bone mineral density in breast cancer patients was significantly higher than that in controls (0.89+/-0.12 g/cm(2) versus 0.84+/-0.16 g/cm(2), P<0.01). The Z-score in breast cancer patients was also higher than that in controls (110+/-13.6% versus 100+/-9.8%, P<0.001). Higher BMD and Z-score in breast cancer patients remained significant after adjusting for age, YSM, and BMI (P<0.05). CONCLUSIONS: Postmenopausal breast cancer patients with positive ER tumor status have higher BMD. Positive ER tumor status may be associated with higher cumulative exposure to estrogen.     

TFF3 is a normal breast epithelial protein and is associated with differentiated phenotype in early breast cancer but predisposes to invasion and metastasis in advanced disease

The trefoil protein TFF3 stimulates invasion and angiogenesis in vitro. To determine whether it has a role in breast tumor metastasis and angiogenesis, its levels were measured by immunohistochemistry in breast tissue with a specific monoclonal antibody raised against human TFF3. TFF3 is expressed in normal breast lobules and ducts, at higher levels in areas of fibrocystic change and papillomas, in all benign breast disease lesions, and in 89% of in situ and in 83% of invasive carcinomas. In well-differentiated tumor cells, TFF3 is concentrated at the luminal edge, whereas in poorly differentiated cells polarity is inverted and expression is directed toward the stroma. Expression was high in well-differentiated tumors and was associated significantly with low histological grade and with estrogen and progesterone receptor expression, accordant with induction of TFF3 mRNA by estrogen in breast cancer cells. Paradoxically, TFF3 expression was associated with muscle, neural, and lymphovascular invasion and the presence and number of involved lymph nodes, and it was an independent predictive marker of lymphovascular invasion and lymph node involvement. Consistent with an angiogenic function, TFF3 expression correlated strongly with microvessel density evaluated with CD31 and CD34. In conclusion, TFF3 is expressed in both the normal and diseased breast. Although associated with features of good prognosis, its profile of expression in invasive cancer is consistent with a role in breast tumor progression and tumor cell dissemination.     

Comparison of monoclonal immunocytochemical and immunoenzymatic methods for steroid receptor evaluation in breast cancer

The production of monoclonal antibodies against estrogen receptor (ER) and progesterone receptor (PR) has permitted the development of the enzyme immunoassay (EIA) and immunocytochemical assay (ICA) for steroid receptor determination. The results obtained with these two techniques, using the same monoclonal antibodies, were compared in a large series of breast carcinomas (187 for ER and 100 for PR). The correlation between these methods was significant for ER (rs = 0.54) and PR (rs = 0.55) (P less than 0.001) but was lost when the receptor concentrations determined by EIA were less than or equal to 15 and less than or equal to 30 fmol/mg protein for ER and PR, respectively. When these values are considered as cutoffs, the concordance between the two methods was 84.5% for ER and 73% for PR. An analysis of discordant results revealed that low epithelial cellularity generally was present in ICA-positive, EIA-negative specimens, whereas only focal positivity with ICA, or positivity of only normal peripheral mammary ducts and lobules, frequently was found in ICA-negative, EIA-positive tumors. In conclusion, there is good correlation between the results obtained by EIA and ICA methods for detection of ER and PR. The authors suggest that biochemical and histochemical methods for steroid receptors could be considered complementary and used together for the analysis of breast cancer.     

Sebaceous carcinoma of the breast

Sebaceous carcinoma (SC) of the breast is a rare malignant tumor and only nine cases, including the present one, have been reported in the English-language literature. The present report describes a case of mammary SC in a 50-year-old Japanese woman. The tumor was gray–white on cut surface and separate from the skin and the nipple. Microscopically, lobules encircled by a fibrous envelope and cords or small cell nests in the stroma were noted. These two types of structures were composed of dark cells and clear foamy cells. The dark cells had large nuclei and amphophilic cytoplasm. The clear foamy cells had numerous lipid vacuoles, confirmed on immunostaining with anti-adipophilin antibody and electron microscopy. In the lobules the gradual transitions from basal dark cells to central clear foamy cells and comedo-like necrosis were observed. The tumor cells were positive on immunohistochemistry for cytokeratins (CAM5.2, AE1/AE3), Her2/neu and androgen receptor but negative for estrogen and progesterone receptors. This is the first case of an androgen receptor-positive mammary SC to be reported, and therefore contributes to the understanding of the clinicopathological features of SC of the breast.     

Effects of testosterone and estrogen treatment on the distribution of sex hormone receptors in the endometrium of postmenopausal women

OBJECTIVE: Our aim was to investigate the effects of the addition of testosterone to estrogen compared with those of estrogen alone on the expression and distribution of sex hormone receptors in glands and stroma of the endometrium of postmenopausal women. DESIGN: An open, randomized clinical study with parallel group comparison was performed in the Women's Health Research Unit at a university hospital. Thirty-one postmenopausal women were given oral estradiol valerate (2 mg daily) or estradiol valerate in combination with testosterone undecanoate (40 mg every 2 days) for 3 months. Before and at the end of treatment, endometrial biopsy samples were obtained, and expressions of estrogen receptor (ER)-alpha, ER-beta, progesterone receptor isoforms A and B, and androgen receptor (AR) were evaluated by immunohistochemical analysis. RESULTS: At baseline, expressions of ER-alpha and progesterone receptors were stronger in glands than in stroma, whereas the immunostaining of AR was stronger in stroma than in glands. After treatment, expressions of ER-alpha and progesterone receptors were up-regulated in both glands and stroma by both treatments, but to a lesser extent in glands by combined treatment. The expression of ER-beta in glands was significantly higher with combined treatment than with estrogen alone. Moreover, AR immunostaining was significantly higher after combined treatment than after treatment with estrogen alone. CONCLUSIONS: Expressions of AR and ER-beta were stronger in glands of the endometrium of postmenopausal women after treatment with testosterone added to estrogen than after estrogen alone. In contrast, expressions of ER-alpha and progesterone receptors were up-regulated in the endometrium with estrogen-alone treatment, whereas these expressions were less increased in glands after combined treatment. These data indicate that testosterone is involved in the regulation of sex hormone receptor expression in the postmenopausal endometrium and may therefore influence endometrial proliferation and differentiation.     

Selective estrogen receptor modulators (SERMs) and retinoids in breast cancer chemoprevention

Tamoxifen has been shown to decrease the risk of invasive breast cancer by 49% and noninvasive breast cancer by 50%. Tamoxifen is also associated with a threefold increased risk of endometrial cancer. Raloxifene, a second-generation selective estrogen receptor modulator (SERM), has not been associated with endometrial cancer risk, and is currently under study in a large, multi-institutional, randomized Study of Tamoxifen and Raloxifene (STAR) for breast cancer prevention in postmenopausal women. A pilot trial of raloxifene in premenopausal women to assess the safety, tolerability, effects on bone mineral density, mammographic density, and other biological endpoints is ongoing. The retinoids have been shown to decrease mammary tumors in rodent carcinogenesis models. The Italian trial of fenretinide (4-HPR) in women with stage I breast cancer randomized women to fenretinide or no intervention. This study did not show an overall effect of decreasing the risk of contralateral breast cancer. However, a protective effect was suggested in premenopausal women. It has been suggested that this effect may be related to insulin-like growth factor 1 (IGF-1), which has been shown to be modulated by fenretinide in premenopausal but not postmenopausal women. Pilot studies of SERMs alone and in combination with retinoids or other agents provide a model for testing the safety and tolerability, pharmacokinetics and pharmacodynamics, and biomarker modulation in high-risk women. These studies can provide information as to both the pathophysiology of carcinogenesis and the mechanism of action of chemopreventive agents, and help select agents and doses for testing in large randomized studies.     

Androgen receptor expression in estrogen receptor-negative breast cancer. Immunohistochemical, clinical, and prognostic associations

We sought to determine the prevalence of androgen receptor (AR) expression in a predominantly estrogen receptor (ER)-negative subset of breast cancers and delineate the immunohistochemical and clinical associations, including whether AR expression has prognostic significance in ER-negative tumors. We identified 69 ER-negative and 19 ER-positive breast cancer cases with concurrent immunohistochemical prognostic panels (ER, PR, HER-2/neu, Ki-67, and p53); immunohistochemical analysis was performed for AR using standard techniques. Clinical data were extracted from medical records. chi 2 tests were used to assess associations between variables. AR was found in 49% (34/69) of ER-negative and 89% (17/19) of ER-positive cases. In ER-negative tumors, AR was associated with increased age (P = .02), postmenopausal status (P < .001), tumor grade (P = .03), tumor size (P = .03), and HER-2/neu overexpression (P = .003). In ER-positive tumors, AR was associated with progesterone receptor expression (P < .03). In univariate analysis of ER-negative tumors, patients with AR-positive tumors had significantly better disease-free survival (P = .049). AR is expressed in a significant number of ER-negative cases and shows significant associations with important clinical and pathologic prognostic factors.     

Postmenopausal hormone therapy before and after breast cancer: clinical experiences

Conventional oestrogen-based hormone therapy (HT) increases the incidence of breast pain and tenderness, mammographic density and the risk of breast cancer. Combined oestrogen plus progestogen therapy (EPT) increases the risk of breast cancer to a greater degree than oestrogen alone (ET). Attention must therefore be focused on identifying women at risk of breast cancer or on producing a HT that has fewer breast side effects. Randomised controlled trials have shown that while EPT induces breast tenderness or pain in up to 50% of women and increases mammographic density in up to 70% during the first year of treatment, only about as many as one-tenth women report breast tenderness or pain with tibolone and increases in mammographic density are rare, occurring with a similar incidence as seen in untreated controls. Many women with breast cancer suffer vasomotor symptoms rather than risk recurrence with conventional HT. However, in a small randomised controlled trial in women with early breast cancer undergoing adjuvant tamoxifen treatment, tibolone reduced hot flushes, night sweats and improved quality of life compared with placebo.     

VEGF expression is associated with negative estrogen receptor status in patients with breast cancer

The aim of this study was to analyze the association between vascular endothelial growth factor (VEGF) expression on tumor cells and other clinicopathologic parameters in breast cancer that could give additional information on its prognostic significance. Immunohistochemical analysis of expression of VEGF, estrogen (ER) and progesterone receptor (PR), HER-2/neu, and Ki67 was performed in 233 breast cancers. VEGF expression estimated semiquantitatively was correlated with all the above-mentioned parameters as well as with clinicopathologic characteristics of breast cancer such as menopausal status of patients, tumor size, histologic and nuclear grade, vascular invasion, and lymph node status. Most of the tumor cells and some stromal components expressed VEGF. A higher percentage of VEGF-positive tumor cells was present in premenopausal patients and in ER-negative tumors. In postmenopausal patients tumors with a higher expression of VEGF were associated not only with ER-negative but also with HER-2/neu-positive tumor cells. These ER-negative tumors were characterized by a higher proliferative activity. Angiogenic switch as well as proliferative activity of breast cancer cells probably are unfavorably dependent on estrogen activity. This negative correlation between VEGF expression and ER status may not only shed more light on tumor biology but may also have future therapeutic implications.     

Progesterone receptor by immunohistochemistry and clinical outcome in breast cancer: a validation study.

Progesterone receptor is a surrogate marker of estrogen receptor activity in breast cancer and its utility in helping predict clinical outcome has been established using biochemical assays. However, most laboratories worldwide have switched to immunohistochemistry to assess progesterone receptor, but unfortunately no validated immunohistochemical assay exists for progesterone receptor. The purpose of this study was to develop and validate an immunohistochemical assay for progesterone receptor in breast cancer. The assay was based on monoclonal antibody 1294 (DakoCytomation) and slides were scored microscopically using the 'Allred score' on a scale of 0-8. The assay was compared to ligand-binding assay in 1235 breast cancers, and a subset (n=362) that received only hormonal therapy was used to define a cutoff for progesterone receptor-positive. Clinical utility was validated in an independent set of samples (n=423) from a clinical trial randomizing premenopausal breast cancer patients to tamoxifen+oophorectomy vs observation following surgery. A cutoff of >2 (corresponding to >1% positive cells) dichotomized patients with significantly better or worse clinical outcome (P=0.0014). Progesterone receptor by immunohistochemistry provided significantly better results than progesterone receptor by ligand-binding assay in predicting clinical outcome. In the clinical trial, a positive result in univariate analyses was associated with significantly improved disease-free and overall survival both in untreated (hazard ratios/P=0.656/0.060 and 0.479/0.005, respectively) and hormonally treated patients (hazard ratios/P=0.529/0.017 and 0.451/0.007, respectively). Positive progesterone receptor remained significant for improved disease-free and overall survival (hazard ratios/P=0.666/0.038 and 0.549/0.007, respectively) in multivariate analyses including the standard variables of tumor size, nodal status, treatment, histological grade, and HER-2/neu status. Estrogen and progesterone receptors are codependent variables and progesterone receptor was a weaker predictor of response to endocrine therapy than estrogen receptor when both were included in multivariate analysis. This is the first comprehensive study assessing the clinical usefulness of progesterone receptor by immunohistochemistry in archival tissue in breast cancer. Progesterone receptor assessed by immunohistochemistry provides useful information about clinical outcome and it is better than progesterone receptor measured by ligand-binding assay.     

Immunohistochemical expression of gonadotropin releasing hormone receptor in human breast carcinoma

Gonadotropin releasing hormone (GnRH) analogs can cause regression of hormone-dependent breast carcinomas via the specific GnRH receptor (GnRH-R). In an attempt to obtain a better understanding of GnRH actions in human breast carcinoma, the expression of GnRH-R was examined immunohistochemically in 58 invasive ductal carcinomas and correlated with various clinicopathological parameters. GnRH-R was immunolocalized in the cytoplasm of carcinoma cells in 37 of 58 invasive ductal carcinoma cases (64%). Immunoreactivity for GnRH-R was also detected focally in the cytoplasm of morphologically normal glandular epithelia adjacent to the carcinoma. A significant correlation was observed between the immunohistochemical expression of GnRH-R and estrogen receptor labeling index (LI; P = 0.030) or progesterone receptor LI (P = 0.0074). There was a significant inverse correlation between GnRH-R immunoreactivity and Ki-67 LI (P = 0.012). No significant correlations were detected between GnRH-R and other clinicopathological parameters, including patient age, menopausal status, stage, tumor size, lymph node status, histological grade and prognosis. This study indicates that GnRH-R is widely distributed in human breast carcinoma cells and regulates GnRH actions locally. Breast carcinomas positive for GnRH-R maintain some hormonal regulatory mechanisms, and GnRH actions may lead to a low proliferative rate in human breast carcinoma.     

Interaction between menopausal status and obesity in affecting breast cancer risk

Obesity has a complex relationship to breast cancer risk that differs in premenopausal and postmenopausal women. Before the menopause, the level of adiposity is inversely related to risk, indicative of a protective effect, whereas in postmenopausal women, particularly the elderly, the association is a positive one, consistent with obesity being a risk factor. The importance of high estrogen production in adipose tissue, with consequent elevation of circulating biologically available estradiol, in the promotional effect of obesity on postmenopausal breast carcinogenesis is well established; the resulting tumors express both estrogen and progesterone receptors. The mechanism(s) for the protective effect in premenopausal women is less well understood, but the breast cancers that do develop in the presence of obesity are most often estrogen and progesterone receptor negative, consistent with the selection of non-estrogen-dependent tumor cells which are dependent on growth factors such as insulin, insulin-like growth factor-I and some adipokines. The influence of menopausal status on the relationships between adiposity and breast cancer appears to be modified within each category by age; the protective effect before the menopause may be limited to younger women (<35 years), and the adverse effect was found to apply specifically to older postmenopausal women. Although randomized trials of weight reduction for postmenopausal breast cancer prevention have not been performed, observational studies suggested that risk reduction does occur; in addition, other health benefits of weight control need to be considered regardless of menopausal status.     

Effects of different types of hormone replacement therapy on mammographic density.

OBJECTIVES: to evaluate the effects of different types of hormone replacement therapy (HRT) on mammographic density in postmenopausal women. METHODS: In a prospective 1-year study, 121 healthy postmenopausal women were allocated to one of the following five study groups: twenty-six women were treated with continuous transdermal 17beta-estradiol 50 mcg/die plus acetate nomegestrolo 5 mg/die sequentially added for 12 days per month (Group A); 25 women were treated with continuous transdermal 17beta-estradiol 50 mcg/die plus acetate nomegestrolo 2.5 mg/die added every day (Group B); 23 women were treated with continuous transdermal 17beta-estradiol 50 mcg/die (Group C); 24 women were treated with tibolone 2.5 mg/die (Group D); and 23 women not receiving any medication represented the control group (Group E). At the time of recruitment and after 12 months a two-view mammography was performed to evaluate mammographic density according to a quantitative method: type 1 (less than 25% of mammary gland covered by dense tissue), type 2 (from 25 to 75% of total glandular area covered by dense tissue), type 3 (more than 75% of mammary parenchyma covered by dense tissue). RESULTS: After 12 months of HRT, seven out of 20 patients (35%) in group A, nine of 21 patients (42.85%) in group B, four out of 19 patients (21%) in group C and two of 20 patients (10%) in group D, showed an increase in mammographic density. No variation of density was observed at the second mammographic test in the control group. The mammographic density increase which occurred in groups A, B and C was statistically significant (P<0.05) when compared with group E; no statistically significant difference (P=0.49) was found in mammographic density increase between group D and group E. When the different treatment types were compared each other, a statistically significant difference (P=0.04) was found only between the mammographic density increase occurring in groups B and D. CONCLUSIONS: HRT may cause an increase of mammographic density. The frequency of the density increase is related to the type of HRT and a replacement therapy including a progestin, especially in continuous combination with estrogen, leads to more evident mammographic changes. Tibolone does not significantly affect mammographic density.