Low-dose Estradiol Research Articles

Prolactinoma induced by estrogen and cyproterone acetate in a male-to-female transsexual

To report a case of a microprolactinoma in a male-to-female transsexual treated with estrogens and cyproterone acetate. Case report. Endocrinology unit in a university hospital. A 33-year-old male-to-female transsexual with prolactin level of 10 ng/mL. Treatment with equine-conjugated estrogens (2.5 mg/day, orally) and cyproterone acetate (100 mg/day, orally) during 6 months. Her levels of prolactin were repeatedly found to be elevated to a maximum of 133 ng/mL, and magnetic resonance imaging (MRI) revealed a pituitary mass of 5x4x4 mm. Discontinuation of the cross-sex hormone treatment did not reduce the levels of prolactin. The use of dopaminergic-agonist therapy normalized them and reduced the size of the microadenoma. After sex-reassignment surgery, she was treated with low-dose estradiol transdermal patches and presented normal levels of prolactin and appropriate levels of 17beta-estradiol and testosterone with a stable image in MRI. We report a case of prolactinoma after treatment with equine-conjugated estrogens and cyproterone acetate. We recommend long-term follow-up observation consisting of a periodic evaluation of prolactin levels and any symptoms suggestive of hyperprolactinemia to detect as early as possible complications derived from cross-sex hormone therapy.

Endometrial Profile of Tamoxifen and Low-Dose Estradiol Combination Therapy

Combination estrogen + progestin therapy has been associated with increased breast cancer risk in postmenopausal women. Selective estrogen receptor modulators (SERM) are potential alternatives to progestins, although the endometrial safety of estrogen + SERM co-therapies is not known. The goal of this study was to evaluate the endometrial profile of low-dose estradiol and the SERM tamoxifen alone and in combination. Twenty-four postmenopausal female cynomolgus macaques were randomized by social group to receive placebo, low-dose micronized estradiol (E(2); 0.25 mg/1,800 kcal), the SERM tamoxifen (Tam; 20 mg/1,800 kcal), or E(2) + Tam for 4 months in a parallel-arm design. Tamoxifen alone resulted in overlapping but distinct effects compared with E(2). Both E(2) and Tam increased uterine weight and endometrial thickness, whereas only E(2) increased endometrial proliferation. Morphologic effects were similar for Tam and E(2) + Tam, which both induced stromal fibrosis and cystic change. Tamoxifen inhibited E(2)-induced proliferation and expression of genes related to cell cycle progression while exhibiting mixed agonist and antagonist effects on gene markers of estrogen receptor activity. The gene expression profile for E(2) + Tam was distinct from either E(2) or Tam alone but dominated by the Tam effect for estrogen-regulated genes. Tam also attenuated E(2) effects on both vaginal maturation and cervical epithelial height. These findings characterize a novel phenotype resulting from estrogen + SERM co-therapy. The predominance of Tam effects on endometrial proliferation, morphology, and transcriptional profiles suggests that endometrial risks for E(2) + Tam may be similar to Tam alone.

Evaluation of gonadotropin‐releasing hormone agonist treatment for prevention of menstrual‐related attacks in acute porphyria

To describe the benefits and adverse effects of gonadotropin-releasing hormone (GnRH) agonist treatment for prevention of recurrent menstrual attacks in women with acute intermittent porphyria and variegate porphyria. To describe concomitant add-back therapies with estradiol and progesterone and describe their benefits and adverse effects. A retrospective follow-up with questionnaires, interviews and medical records. Out-patient care at the Umeå University Hospital in Sweden. Sixteen Caucasian women with DNA-diagnosed porphyria and menstrual-cycle-related porphyria attacks were treated with GnRH agonists during 1984-2000. Fourteen women participated. The mean age when treatment started was 33 years (17-48 years). The duration of treatment varied between 5 months and 9 years. GnRH agonists were administered by the intranasal route or by injections. To reduce menopausal symptoms, add-back therapy with low doses of estradiol was administered, and for endometrial protection progesterone was usually administered. Treatment effects and adverse events as detected in questionnaires, interviews and medical records. Eleven women reported benefits from GnRH agonist treatment with less intense and/or less frequent porphyria attacks, and in four of them attacks almost disappeared. Two women reported no change. One woman had only temporary improvement. Porphyria attacks were triggered by solely estradiol add-back in two women and in five of nine women when progesterone was given. GnRH agonist treatment can ameliorate menstrual-cycle-related attacks of porphyria. Dose findings for GnRH agonists and add-back regimes especially for progesterone are intricate.

Effects of Hormone Therapy on Depressive Symptoms and Cognitive Functions in Women With Alzheimer Disease: A 12 Month Randomized, Double-Blind, Placebo-Controlled Study of Low-Dose Estradiol and Norethisterone

To elucidate the effects of low-dose 17beta-estradiol and norethisterone (hormone therapy [HT]) versus placebo in women with Alzheimer Disease (AD) on cognition, depressive symptoms, and activities of daily living. A 12-month randomized, double-blind, placebo-controlled study, stratified by apolipoprotein E (ApoE) genotype (with versus without the epsilon4 allele), duration of education (< or =9 versus >9 years), and age (< or =75 versus >75 years) performed during 2000-2004. Ambulatory memory clinic in a general hospital. Sixty-five female outpatients aged 65-89 years who met criteria for probable AD according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition and International Classification of Diseases, tenth edition. Ten patients were excluded, resulting in 55 participants who had at least one posttreatment efficacy evaluation. Randomly assigned to receive either 1-mg estradiol and 0.5-mg norethisterone or placebo once daily. Cognitive variables were the Dementia Rating Scale, tests from Consortium to Establish a Registry for AD, Global Deterioration Scale (GDS) and Barthel Index. When only treatment effects were compared by analysis of variance, there were nonsignificant differences between treatment groups for all efficacy variables. A linear model analysis, including stratifying factors in addition to treatment in the model, revealed a significant main effect on mood. The depressive symptoms were lower in the HT group than in the placebo group. Those treated with HT without the ApoE epsilon4 allele had better mood, Word Learning Memory score, and GDS score. Those in the HT group with a higher level of education obtained a better GDS score. Adverse events did not differ between the groups. HT interacts with ApoE genotype in women with AD. Women without an ApoE epsilon4 allele may get better mood and cognition with HT. HT may reduce depressive mood and give less cognitive decline.

Chronic inflammation and estradiol interact through MAPK activation to affect TMJ nociceptive processing by trigeminal caudalis neurons

The mitogen-activated protein kinase/extracellular regulated kinase (MAPK/ERK) pathway plays a key role in mediating estrogen actions in the brain and neuronal sensitization during inflammation. Estrogen status is a risk factor in chronic temporomandibular muscle/joint (TMJ) disorders; however, the basis for this relationship is not known. The present study tested the hypothesis that estrogen status acts through the MAPK/ERK signaling pathway to alter TMJ nociceptive processing. Single TMJ-responsive neurons were recorded in laminae I–II at the spinomedullary (Vc/C1-2) junction in naïve ovariectomized (OvX) female rats treated for 2 days with high-dose (20 μg/day; HE2) or low-dose estradiol (2 μg/day; LE2) and after chronic inflammation of the TMJ region by complete Freund's adjuvant for 12–14 days. Intra-TMJ injection of ATP (1 mM) was used to activate Vc/C1-2 neurons. The MAPK/ERK inhibitor (PD98059, 0.01–1 mM) was applied topically to the dorsal Vc/C1-2 surface at the site of recording 10 min prior to each ATP stimulus. In naïve HE2 rats, low-dose PD98059 caused a maximal inhibition of ATP-evoked activity, whereas even high doses had only minor effects on units in LE2 rats. By contrast, after chronic TMJ inflammation, PD98059 produced a marked and similar dose-related inhibition of ATP-evoked activity in HE2 and LE2 rats. These results suggested that E2 status and chronic inflammation acted, at least in part, through a common MAPK/ERK-dependent signaling pathway to enhance TMJ nociceptive processing by laminae I–II neurons at the spinomedullary junction region.

Estradiol in Breast Cancer Treatment

DESPITE A DECLINING INCIDENCE, BREAST CANCER REmains the most common cancer among women in the United States. More than two-thirds of all patients with breast cancer present with tumors that express estrogen receptors, progesterone receptors, or both, and the modulation of estrogen receptor signaling has been one of the most successful strategies for these patients. In recent years, the most commonly used forms of endocrine therapy have included the competitive inhibition of the estrogen receptors with an antiestrogen (selective estrogen receptor modulators [SERMs], eg, tamoxifen, or selective estrogen–receptor down-regulators, [SERDs], eg, fulvestrant) and the decrease in estrogen production from precursor steroid hormones using an aromatase inhibitor. In this issue of JAMA, Ellis and colleagues describe the findings of a preliminary phase 2 randomized study, evaluating the efficacy of 2 daily doses of oral estradiol (30 mg vs 6 mg). The study included 66 postmenopausal women with hormone receptor–positive metastatic breast cancer, who had received prior therapy with an aromatase inhibitor for at least 24 weeks for metastatic disease or for at least 2 years as adjuvant therapy. The authors reported a clinical benefit for 29% of patients (10/34) treated with the low-dose (6 mg) therapy and for 28% of those (9/32) treated with high-dose (30 mg) therapy. Grade 3 and 4 toxicities were significantly more common in patients receiving the higher dose of estradiol. The adverse effects associated with the 30-mg dose of estradiol led to treatment discontinuation in 4 of 32 patients and required a dose reduction in 4 patients, whereas only 1 patient withdrew from therapy at the lower dose for personal reasons. Estradiol-related pharmacodynamic end points, including changes in the fluorodeoxyglucose–positron-emission tomography/computed tomography (FDG-PET/CT) uptake over 24 hours after estradiol initiation and a decrease in the expression of insulinlike growth factor (IGF-1), were observed in both groups. The increase in the specific uptake value by FDGPET/CT in predefined tumor sites appeared predictive of response, although data were available for only 70% (46) of the patients. Based on the promising efficacy data and the acceptable toxicity profile observed with the low-dose estradiol, the authors suggest that further studies exploring this intervention should be pursued in larger randomized phase 3 trials. Synthetic estrogens were an integral part in the armamentarium of breast cancer for several decades. First synthesized in 1938, diethylstilbestrol (DES) was approved as a synthetic estrogen by the US Food and Drug Administration in 1941, and recommended as a treatment for breast cancer for postmenopausal women in 1960. Very high doses of estrogen were further tested in premenopausal women, albeit with more limited success. The use of estrogens for the treatment of breast cancer was largely empirical and perhaps counterintuitive because the benefits of estrogen withdrawal by oophorectomy, adrenalectomy, and hypophysectomy were well-recognized by that time as a treatment for breast cancer in both premenopausal and postmenopausal women by that time. Furthermore, formal testing of estrogen receptor expression was not yet available. High doses of estrogens remained one of the few nonsurgical options for breast cancer treatment until the introduction of the antiestrogen tamoxifen in 1971. A small randomized phase 2 trial evaluating 2 doses of tamoxifen in postmenopausal women with advanced breast cancer and prior exposure to hormonal manipulations showed sustained activity with acceptable toxicity with this agent, which had been unsuccessfully developed as a contraceptive. Further studies comparing tamoxifen with DES showed that DES and tamoxifen elicited similar results in terms of response rates and time to tumor progression; however, tamoxifen treatment led to far fewer adverse effects and treatment discontinuations. The subsequent introduction of thirdgeneration aromatase inhibitors and the approval of the SERD fulvestrant rendered synthetic estrogens a less desirable alternative, and high-dose estrogens have been rarely used in recent years. Furthermore, changes in practice patterns have shifted the use of chemotherapy more to the foreground, even for women with hormone receptor–positive tumors. The interest in estrogens as therapy for metastatic breast cancer was rekindled when Lonning et al reported a ben-

Lower-Dose vs High-Dose Oral Estradiol Therapy of Hormone Receptor–Positive, Aromatase Inhibitor–Resistant Advanced Breast Cancer

Estrogen deprivation therapy with aromatase inhibitors has been hypothesized to paradoxically sensitize hormone-receptor-positive breast cancer tumor cells to low-dose estradiol therapy. To determine whether 6 mg of estradiol (daily) is a viable therapy for postmenopausal women with advanced aromatase inhibitor-resistant hormone receptor-positive breast cancer. A phase 2 randomized trial of 6 mg vs 30 mg of oral estradiol used daily (April 2004-February 2008 [enrollment closed]). Eligible patients (66 randomized) had metastatic breast cancer treated with an aromatase inhibitor with progression-free survival (> or = 24 wk) or relapse (after > or = 2 y) of adjuvant aromatase inhibitor use. Patients at high risk of estradiol-related adverse events were excluded. Patients were examined after 1 and 2 weeks for clinical and laboratory toxicities and flare reactions and thereafter every 4 weeks. Tumor radiological assessment occurred every 12 weeks. At least 1 measurable lesion or 4 measurable lesions (bone-only disease) were evaluated for tumor response. Randomization to receive 1 oral 2-mg generic estradiol tablet 3 times daily or five 2-mg tablets 3 times daily. Primary end point: clinical benefit rate (response plus stable disease at 24 weeks). toxicity, progression-free survival, time to treatment failure, quality of life, and the predictive properties of the metabolic flare reaction detected by positron emission tomography/computed tomography with fluorodeoxyglucose F 18. The adverse event rate (> or = grade 3) in the 30-mg group (11/32 [34%]; 95% confidence interval [CI], 23%-47%) was higher than in the 6-mg group (4/34 [18%]; 95% CI, 5%-22%; P = .03). Clinical benefit rates were 9 of 32 (28%; 95% CI, 18%-41%) in the 30-mg group and 10 of 34 (29%; 95% CI, 19%-42%) in the 6-mg group. An estradiol-stimulated increase in fluorodeoxyglucose F 18 uptake (> or = 12% prospectively defined) was predictive of response (positive predictive value, 80%; 95% CI, 61%-92%). Seven patients with estradiol-sensitive disease were re-treated with aromatase inhibitors at estradiol progression, among which 2 had partial response and 1 had stable disease, suggesting resensitization to estrogen deprivation. In women with advanced breast cancer and acquired resistance to aromatase inhibitors, a daily dose of 6 mg of estradiol provided a similar clinical benefit rate as 30 mg, with fewer serious adverse events. The efficacy of treatment with the lower dose should be further examined in phase 3 clinical trials. clinicaltrials.gov Identifier: NCT00324259.

Low doses of estradiol partly inhibit release of GH in sheep without affecting basal levels

Estradiol increases basal growth hormone (GH) concentrations in sheep and cattle. This study sought to determine the effects of estradiol on GH-releasing hormone (GRH)-stimulated GH release in sheep. Growth hormone secretory characteristics, the GH response to GRH, and steady-state GH mRNA concentrations were determined in castrated male lambs treated with 2 different doses of estradiol 17-β for a 28-d experimental period. Although no differences between treatments in mean GH, basal GH, or GH pulse number were observed after 28 d of estradiol treatment, GH pulse amplitude was greater ( P < 0.05) in the 2.00-cm implant-treated animals than in the control and 0.75-cm implant group. The effect of estradiol treatment on GRH-stimulated GH release revealed differences between the control and estradiol-treated animals ( P < 0.05). The 15-min GH responses to 0.075 μg/kg hGRH in the control, 0.75-cm, and 2.00-cm implant groups, respectively, were 76 ± 10, 22.6 ± 2.1, and 43.6 ± 15.0 ng/mL. Growth hormone mRNA content was determined for pituitary glands from the different treatment groups, and no differences in steady-state GH mRNA levels were observed. There were no differences in the mean plasma concentrations of IGF-I, cortisol, T 3, or T 4 from weekly samples. Growth hormone release from cultured ovine pituitary cells from control sheep was not affected by estradiol after 72 h or in a subsequent 3-h incubation with estradiol combined with GRH. These data suggest that estradiol has differing actions on basal and GRH-stimulated GH concentrations in plasma, but the increase in pulse amplitude does not represent an increased pituitary sensitivity to GRH.

Low-dose transdermal estradiol induces breast density and heterogeneity changes comparable to those of raloxifene

The aim of this study was to investigate whether transdermal low-dose estradiol treatment induces changes in mammographic density or heterogeneity compared with raloxifene, whether if these changes relate to changes in bone formation/resorption markers, and whether these findings indicate elevation of breast cancer risk by treatment. Digitized mammograms of 2 x 135 completers of a 2-year, randomized trial formed the base of the present analysis. Active treatments were transdermal estradiol releasing 0.014 mg estradiol (E2)/week and orally administered raloxifene hydrochloride 60 mg/day, respectively. Influence of the therapies on breast density was assessed with categorical scores Breast Imaging Reporting and Data System, area percentage density, and computer-based (E2-specific) heterogeneity examination of radiographs. These where related to physical and systemic markers. At baseline, no mammography scoring methodology or other marker could separate the two treatment groups of transdermal estradiol and raloxifene. No treatment induced significant density changes measured by Breast Imaging Reporting and Data System. Both treatments made the area percentage density increase and the estradiol significantly. Both treatments induced significant changes in E2-specific heterogeneity scoring (E2-specific heterogeneity examination of radiograph), and the raloxifene treatment induced a significantly higher change. At baseline, the mammographic markers showed negative correlation with body mass index and positive correlation with serum type I collagen crosslinks C-telopeptide. The changes in mammographic markers did not essentially exhibit correlations to changes in bone markers in either treatment group. Low-dose transdermal estradiol and raloxifene induced comparable changes in breast density and heterogeneity. Baseline correlations may be explained through relations to obesity. The current study does not yield evidence against the hypothesis that "neither raloxifene nor low dose transdermal estradiol treatment increases the breast cancer risk."

Hormonal Therapies and Venous Thrombosis

Prothrombotic effects of HRT are related to several actions. Low doses of oestradiol are associated with less activation of coagulation, including TFPI and APC Resistance, and inflammatory markers if compared with regular dose: low dose and conventional dose formulations had similar effects on C reactive protein [11, 12]; however also the increase synthesis of clotting factors as to the decreased synthesis of clotting inhibitors as to an acquired form of activated protein C resistance are involved in the hypercoagulable state of women ongoing HRT [1]. As confirm of this trend to hypercoagulable state, markers of thrombin generation are frequently increased in women taking HRT: increased levels of prothrombin fragments 1+2, TAT complexes and D-dimer have been found in several studies [13]. Furthermore the increase in these markers was higher in women who subsequently developed recurrent VTE.

Magnetic Resonance Imaging quantification of breast density in BRCA carriers following gonadotropin releasing hormone agonist (GnRHA)-based hormonal chemoprevention

1506 Background: Breast tissue density limits the usefulness of mammography as a surveillance tool in young women. Breast Magnetic Resonance Imaging (MRI) provides high tissue contrast and three-dimensional structural information not impaired by high breast density. We developed a volumetric “MR density” measure of breast structural composition that may be complementary to mammographic breast density. We tested this MR density measure in unaffected women with known high risk of breast cancer due to a BRCA gene mutation (or empiric risk &gt; 30% lifetime), who were recruited in a phase II trial to study the effects of a hormonal chemoprevention regimen. Methods: Nine premenopausal high-risk women age 21 to 48 were treated with intranasal GnRHA (deslorelin), low-dose estradiol, and testosterone daily for 10 months. All patients underwent one contrast-enhanced breast MRI exam before and after treatment. We measured MR density as the ratio of fibroglandular tissue volume to total volume of the breast, at both time points. Our technique involved the semi-automated delineation of the breast and the automated segmentation of fibroglandular from adipose tissue. An “MR index” was also defined to quantify partial voluming effects due to the presence of adipose/fibroglandular edges in the MR data. Results: Eight out of nine patients showed a reduction in MR density (p = 0.026) with treatment. Three patients had less than 5% MR density at baseline, making it difficult to quantitate a change with treatment. All of the remaining six patients had reduced MR density after treatment (mean reduction 35.5%; p = 0.035). Conclusions: We have demonstrated the use of breast MR density as a robust volumetric quantitative measure of breast tissue composition. Our findings suggest that MR could be used to measure hormonal chemoprevention effects in BRCA carriers. [Table: see text]

Effects of Steroid Hormones on Morphology and Vascular Endothelial Growth Factor Expression in Female Bladder

To investigate the roles of steroid hormones, including estrogen, progesterone, and testosterone, in the morphology and vascularization of the female bladder. A total of 70 adult, female Sprague-Dawley rats were divided into 7 groups: group 1, sham; group 2, ovariectomized rats without treatment; group 3, low-dose estradiol; group 4, high-dose estradiol; group 5, progesterone; group 6, estradiol combined with progesterone; and group 7, testosterone. All were given for 4 weeks. The serum steroid hormone levels were determined by radioimmunoassay. The total weight and thickness of the bladder were measured. Morphologic changes were observed under light and electron microscopy. The expression of vascular endothelial growth factor (VEGF) in the bladder was evaluated by immmohistochemistry and Western blotting. The ovariectomized rats had a thinner bladder wall compared with the sham group (0.97 +/- 0.11 mm vs 1.10 +/- 0.10 mm, P < .05) and widened spaces between the detrusor muscle fascicles with collagen deposit. Estrogen reversed these changes, and testosterone increased the thickness of the bladder wall to 1.26 +/- 0.12 mm (P < .05). VEGF staining was mainly located in the urothelium and endothelial cells, with weak staining in the smooth muscles. VEGF was almost absent in the urothelium after ovariectomy. In the estrogen- and androgen-treated groups, although the expression of VEGF was significantly greater than that in the nontreated ovariectomized group, it was still lower than normal. Our findings suggest the importance of steroid hormones in maintaining the integrity of the bladder structure and regulating the expression of VEGF in the female urinary tract. Both estrogen and androgen can reverse the bladder muscle atrophy induced by ovariectomy. However, the decline in VEGF expression in the bladder cannot be fully recovered with either estrogen or androgen replacement.

Estradiol-induced, endothelial progenitor cell-mediated neovascularization in male mice with hind-limb ischemia

We investigated whether administration of estradiol to male mice augments mobilization of bone marrow-derived endothelial progenitor cells (EPC) and incorporation into foci of neovascularization after hind-limb ischemia, thereby contributing to blood flow restoration. Mice were randomized and implanted with placebo pellets or pellets containing low-dose estradiol (0.39 mg) or high-dose estradiol (1.7 mg). Hind-limb ischemia was induced by unilateral resection of the left femoral artery 1 week after pellet implantation, then EPC mobilization and functional recovery was evaluated. EPC recruitment was assessed in mice transplanted with bone marrow from transgenic donors expressing beta-galactosidase driven by the Tie-2 promoter. EPC culture assay performed 2 weeks after pellet implantation revealed a significantly greater (p<0.05) number of circulating EPCs in the high-dose estradiol group than in the low-dose estradiol and placebo groups. At 3 and 4 weeks after induction of hind-limb ischemia, perfusion was significantly greater (p<0.05) in high-dose estradiol mice than in mice implanted with the low-dose estradiol or placebo pellets. At 1 and 4 weeks after hind-limb ischemia surgery, more bone marrow-derived EPCs, identified as beta-galactosidase-positive cells, were observed in ischemic regions from high-dose estradiol animals than in low-dose (p<0.05) or placebo groups (p<0.05). These results indicate that estradiol dose-dependently increases the levels of EPCs in peripheral blood in male animals, improves the recovery of blood flow, and decreases limb necrosis after hind-limb ischemia, and that this enhancement occurs, in part, through augmentation of EPC mobilization and greater incorporation of bone marrow-derived EPCs into foci of neovascularization.

A randomized phase 2 trial of low dose (6 mg daily) versus high dose (30 mg daily) estradiol for patients with estrogen receptor positive aromatase inhibitor resistant advanced breast cancer.

Abstract Abstract #16 Rationale: It has been postulated that aromatase inhibitor (AI) therapy may sensitize ER+ breast cancer to lower doses of estrogen therapy as second-line endocrine treatment for advanced breast cancer (ABC). We therefore conducted a randomized trial of 30mg generic estradiol daily (10 mg t.i.d.- "recommended" dose) versus 6 mg (2 mg t.i.d - "experimental" dose).&amp;#x2028; Materials and Methods: Major eligibility: Postmenopausal ER+ ABC treated with an AI with 24+ wks progression free survival, or relapse after 2+ yrs of adjuvant AI; RECIST measureable non-bone metastases or WHO assessable bone lesions, with elevated tumor markers &amp;gt;2X ULN. Major exclusions: History venous thrombosis, heart disease, uncontrolled hypercalcemia and fulvestant in the last 12 months. FDG PET scans were conducted at baseline and after 24 hours to assess metabolic flare as a predictor of response (pre-defined as a ≥12% increase in FDG uptake).&amp;#x2028; Results: Sixty-six patients were enrolled (82% White, 15% Black); mean age 59 years, range 36-84. 34 received 6 mg and 32 received 30 mg. Estradiol levels will be provided at the meeting. There were more patients experiencing grade 3+ SAE on the 30 mg arm versus the 6 mg arm (11 vs. 4; P=0.06) with one venous thrombosis on each arm. There was no difference in total FACT-B QOL scores at one month by treatment arm, QOL decline was associated with more severe estrogen side effects, especially amongst patients on the 30 mg arm (P=0.006). Uterine bleeding was successfully controlled with intermittent progestin therapy. Clinical benefit rates (stable disease at least 24 weeks plus response - intent to treat population) were 25% (CI: 15-37%, 1PR and 7SD out of 32) on the 30 mg arm and 29% (CI: 19-42%, 3PR and 7SD out of 34) on the 6 mg arm. Patients with clinical benefit to estradiol could be retreated with original AI after progression and to date one PR out of three patients with repeat AI therapy noted. There were 44 patients evaluable for the interaction between PET -flare and response. Flare was seen in all responders (3/3), 9 of 13 patients with SD and only 3 of 30 patients with PD (p&amp;lt;0.0001). PPV for PET flare was therefore 12/15 (80%, CI: 61-92%) and NPV 27/31 (87%, CI: 76-94%). &amp;#x2028; Conclusions: The Protocol Review and Monitoring Committee closed the 30 mg arm early after they concluded that the 6 mg arm was as effective as the 30 mg arm with greater safety. We therefore recommend 6 mg as the appropriate dose for the palliative treatment of advanced ER+ breast cancer. FDG PET flare can be used to identify patients who have a high chance of clinical benefit.&amp;#x2028; Supported by an AVON NCI Partners in Progress Award: Grant # P30 CA091842-S4. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 16.

Interactive effects of low-dose estradiol and tamoxifen on the postmenopausal primate endometrium and mammary gland.

Abstract Abstract #3047 Background: Long-term use of combined estrogen+progestin hormone therapies increases breast cancer risk in postmenopausal women. Selective estrogen receptor modulators (SERMs) are promising alternatives to progestins, particularly for breast cancer survivors and other women at high-risk for breast cancer considering hormone therapy. The purpose of this study was to evaluate interactive effects of low-dose estradiol (E2) and the SERM tamoxifen on the postmenopausal endometrium and mammary gland.&amp;#x2028; Materials and Methods: Ovariectomized adult female cynomolgus monkeys were given placebo (n=6), oral estradiol (E2, 0.25 mg/1800 kcal) (n=6), tamoxifen (TAM, 20 mg/1800 kcal) (n=5), or E2+TAM (n=6) for 4 months. Doses of E2 and TAM were scaled to approximate those given to women.&amp;#x2028; Results: Endometrial thickness and uterine weight were significantly higher in E2, TAM, and E2+TAM groups compared to placebo (P &amp;lt; 0.01 for all). In contrast, endometrial gland and stromal proliferation determined by Ki67 immunolabeling was significantly greater only in the E2 group (P &amp;lt; 0.01 for both). Endometrial Ki67 gene expression was also higher only in the E2 group (P &amp;lt; 0.01). Gene markers of estrogen receptor alpha (ER) activity such as TFF1 and STC2 were significantly increased in E2, TAM, and E2+TAM groups (P &amp;lt; 0.01 for all). On endometrial histology TAM and E2+TAM induced stromal fibrosis and occasional simple glandular hyperplasia with cystic change. In the mammary gland, TFF1 gene expression was increased by all treatments (P &amp;lt; 0.05 for all), while no statistically significant treatment effects were seen for epithelial proliferation or progesterone receptor expression.&amp;#x2028; Discussion: Previous studies have suggested that the weak estrogen-like effects of tamoxifen in the uterus contribute to increased endometrial cancer risk. Our findings reveal a more complex pattern of tamoxifen action involving increased ER activity, antagonism of E2-induced proliferation, and distinctive stromal remodeling. These results suggest that tamoxifen does not exhibit simple weak estrogen agonist / antagonist effects in the primate endometrium but instead acts through pathways independent of classical ER signaling to alter cancer risk. Future gene profiling should aid in the identification of these alternative pathways. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3047.

Dissociating the conditioning and the anorectic effects of estradiol in female rats.

The present series of experiments challenges the ability of the hormone estradiol to act as an unconditioned stimulus in the conditioned taste avoidance (CTA) learning paradigm. We hypothesize that reductions in sucrose consumption observed after pairing it with estradiol are not indicative of associative learning, but due to the unconditioned expression of estradiol's anorectic effects during the time of CTA assessment. Three experiments in which a sucrose solution was paired with estradiol were conducted to test this hypothesis. Experiment 1 demonstrated that female rats expressed a reduction in post-pairing sucrose consumption even though the anorectic effects of estradiol had subsided. Experiment 2 showed that although a low dose of estradiol produced anorexia, it did not elicit post-pairing reductions in sucrose consumption. Experiment 3 revealed that contingent pairing was a requirement for post-pairing reduction in sucrose consumption even when testing was done at a time when anorexia is expressed. These findings demonstrate the dissociability of the conditioning and anorectic effects of estradiol, providing evidence against the hypothesis. The results are discussed in terms of independent neural mechanisms underlying the disparate behaviors.

Low-dose estradiol for climacteric symptoms in Japanese women: a randomized, controlled trial

Objectives To investigate two different doses of oral estradiol to reduce the number of hot flushes in Japanese women with climacteric symptoms.Methods Women (n = 211) aged 40–64 years who had experienced natural menopause or bilateral oophorectomy, with ≥ three moderate/severe hot flushes per day in the week before study, were randomized to receive micronized estradiol (E2) 0.5 or 1.0 mg or placebo once daily for 8 weeks. The primary efficacy endpoint was percentage change in mean daily number of hot flushes over 7 days from baseline to final examination.Results Percentage change in mean daily number of hot flushes at final examination was similar for E2 0.5 mg and E2 1.0 mg (−79.58 ± 28.29% vs. −82.49 ± 25.31%, p = 0.555) but was significantly lower with placebo (−57.89 ± 34.15%, p < 0.001 vs. E2, both doses). There was no significant difference in number of treatment-related adverse events occurring in the E2 0.5 and 1.0 mg groups (25% and 36.6%, respectively). The higher E2 dose showed more pronounced effects on symptom severity.Conclusions The dose of 0.5 mg/day was effective as the oral E2 starting dose for treatment of hot flushes in Japanese women.

Menopausal hot flashes are treated effectively by a transdermal, low-dose estradiol spray

This Practice Point commentary discusses a randomized, double-blind, placebo-controlled trial that assessed the use of a transdermal estradiol spray to treat hot flashes in 454 postmenopausal women. Participants applied 1, 2, or 3 daily sprays containing estradiol (1.53 mg per spray) or placebo to the inner aspect of the forearm. Estradiol administered in 1, 2 or 3 daily sprays reduced the daily frequency of hot flashes at week 4 by −6.26, −7.30, and −6.64, respectively (P <0.001, P = 0.003, and P <0.001 compared with placebo, respectively). Participants using 1 spray daily had a mean serum estradiol level of 71.6–84.0pmol/l, which is higher than serum estradiol levels in untreated symptomatic postmenopausal women. These findings indicate that a transdermal estradiol spray can improve menopausal symptoms even at a very low dose. Furthermore, this preparation allows health care providers to individualize the estradiol dose that is required for the control of hot flashes in each patient.

Low-Dose Estradiol Spray: a Novel Treatment for Vasomotor Instability in Postmenopausal Women

This article describes a novel transdermal estradiol spray developed for the treatment of menopausal vasomotor instability. The spray delivers estradiol directly into the subcutaneous microcirculation achieving the advantages of estradiol patches, creams and gels but with minimal skin reaction, patient inconvenience or cosmetic shortcomings associated with transdermal methods. In the one published Phase III clinical trial, postmenopausal women (n = 454) with eight or more moderate-to-severe hot flashes per day applied each morning, one, two or three estradiol 90 microl sprays (each containing estradiol 1.53 mg) versus matching placebo sprays. There was a significant decrease in hot flash frequency and intensity at weeks 4 and 12 compared with corresponding placebo groups (p < 0.010). The systemic estradiol delivery rates at week 12 were approximately 0.021, 0.029 and 0.040 mg/day for the 1-, 2- and 3-spray doses, respectively. There were common adverse events similar to those previously reported with transdermal estradiol, except for skin irritation, which was very low. The spray is a well-tolerated, cosmetically attractive and convenient method of delivering low-dose, transdermal estradiol.

Effective Treatment of Vaginal Atrophy With an Ultra–Low-Dose Estradiol Vaginal Tablet

To evaluate the efficacy of ultra-low-dose 10-microgram 17beta-estradiol (E2) vaginal tablets for treatment of vaginal atrophy. Postmenopausal women (N=309) were randomly assigned to 10-microgram E2 or placebo vaginal tablets for 52 weeks in a multicenter, double-blind study. Primary efficacy endpoints included change from baseline to week 12 in vaginal cytology, vaginal pH, and most bothersome urogenital symptoms score. Grading of vaginal health was a secondary efficacy assessment. Safety assessments included endometrial biopsy, physical and gynecologic examinations, and recording adverse events. At week 12, the change from baseline for 10 micrograms E2 compared with placebo demonstrated significant improvement in vaginal Maturation Index (proportion of parabasal cells: -37% compared with -9%; superficial cells: 13% compared with 4%; intermediate cells: 24% compared with 5%; P<.001 for each), Maturation Value (25.0 compared with 6.5, P<.001), grading of vaginal health (-0.91 compared with -0.51, P<.001), vaginal pH grade (-1.3 compared with -0.4, P<.001), and most bothersome symptoms score (-1.23 compared with -0.87, P=.003). For each component of vaginal Maturation Index, vaginal Maturation Value, grading of vaginal health, and vaginal pH, treatment effects were statistically different from placebo after 2 weeks of treatment. For most bothersome symptoms, treatment effect became apparent after 4 weeks and reached statistical significance at week 8 of therapy. All treatment effects were statistically significant at week 52. There were no major safety findings regarding physical, gynecologic, or laboratory assessments. After 12 weeks of treatment, an ultra-low-dose 10-microgram E2 vaginal tablet, compared with placebo, demonstrated significant improvement for the primary endpoints: vaginal cytology and pH and most bothersome urogenital symptoms score. ClinicalTrials.gov, http://clinicaltrials.gov, NCT00108849 I.