Changes in serum estrogen levels in women during tamoxifen therapy

Local heating-induced cutaneous vasodilation in reinnervated and noninnervated deep inferior epigastric perforator flaps

INTRODUCTION

Cutaneous vascular reactivity to local heating in free flaps has not been characterized. We aimed to assess local heating-induced cutaneous vasodilation in reinnervated and noninnervated deep inferior epigastric perforator (DIEP) flaps.

METHODS

We conducted a cross-sectional study of 21 female patients with an uncomplicated unilateral delayed DIEP breast reconstruction at least 2 years after surgery. DIEP flaps and contralateral breasts were subjected to direct local heating, and skin blood flow was assessed using laser-Doppler flowmetry. To evaluate sensory-nerve-fiber function, touch perception thresholds were assessed using a 20-piece Touch-test™ Sensory Evaluator, and cutaneous warm detection and heat pain thresholds were measured using a TSA-II device.

RESULTS

Of the participants, 10 had a reinnervated DIEP flap with a single coapted nerve (mean flap weight, 610 ± 296 g) and 11 had a noninnervated DIEP flap (mean flap weight, 613 ± 169 g). Mean age was 58 ± 11 years, mean follow-up time was 5 ± 1 years, and mean BMI was 24 ± 3 kg/m2 . DIEP flaps exhibited significantly weaker cutaneous vasodilation in response to local heating than contralateral breasts (median peak skin blood flow, 59 [25th-75th percentile, 36-71] a.u. for DIEP flaps versus 94 [74-141] a.u. for contralateral breasts; p < .001). The magnitude of the response was similar between reinnervated and noninnervated flaps (median peak skin blood flow, 55 [25th-75th percentile, 39-68] a.u. for reinnervated DIEP flaps versus 66 [36-77] a.u. for noninnervated DIEP flaps; p = .75). Of participants with reinnervated DIEP flaps, 90% perceived heat pain below the 50°C safety threshold, as compared to 36% of participants with noninnervated DIEP flaps (two-tailed p = .02).

CONCLUSION

Our results suggest that free flap transfer causes longstanding impairment, yet not complete abolition, of both the sensory nerve-mediated and nitric oxide-dependent local heating-induced cutaneous vasodilatory systems. We found no statistical evidence that flap reinnervation improves the ability to raise skin blood flow in response to local heating.

Aromatase inhibitors and the incidence of Parkinson disease: A population-based cohort study

BACKGROUND

Current guidelines recommend the treatment of hormone receptor-positive breast cancer with aromatase inhibitors (AIs) and tamoxifen in the adjuvant setting. Some observational studies have raised concerns that tamoxifen may be associated with an increased risk of Parkinson disease (PD). However, no studies have directly compared the risk of PD between AIs and tamoxifen in women diagnosed with breast cancer.

METHODS

Using the UK Clinical Practice Research Datalink, the authors assembled a cohort of women newly diagnosed with breast cancer and newly treated with either AIs or tamoxifen between January 1, 1995, and December 31, 2017. Patients were followed 1 year after treatment initiation (ie, a 1-year lag) until an incident diagnosis of PD or were censored at death from any cause, the date of transfer out of the practice, or the end of the study period (December 31, 2018). Cox proportional hazards models with inverse probability of treatment weights were used to estimate weighted hazard ratios (HRs) and 95% confidence intervals (CIs) for PD comparing AIs with tamoxifen and accounting for more than 30 confounders.

RESULTS

In all, 30,140 women with nonmetastatic breast cancer were identified: 13,838 initiated AIs, and 16,302 initiated tamoxifen. Compared with tamoxifen, AIs were not associated with an increased risk of PD (HR, 0.94; 95% CI, 0.60-1.47). Consistent results were observed across all secondary and sensitivity analyses.

CONCLUSIONS

In this large observational study, the use of AIs, in comparison with tamoxifen, was not associated with an increased risk of PD in women diagnosed with nonmetastatic breast cancer in a real-world setting.

LAY SUMMARY

Previous studies have indicated that tamoxifen may increase the risk of Parkinson disease in the treatment of breast cancer. However, no studies have directly compared the risk of Parkinson disease between aromatase inhibitors and tamoxifen. This study included 30,140 women diagnosed with breast cancer and treated with aromatase inhibitors or tamoxifen. Overall, compared with tamoxifen, aromatase inhibitors were not associated with an increased risk of Parkinson disease in women diagnosed with breast cancer. This study provides an important addition to the comparative safety profile of aromatase inhibitors and tamoxifen in the treatment of breast cancer.

The Effect of Raloxifene Treatment on Lipid Profile in Elderly Individuals: A Systematic Review and Meta-analysis of Randomized Clinical Trials

PURPOSE

To perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to elucidate the effects of raloxifene on the lipid profile in elderly individuals.

METHODS

A systematic review and meta-analysis of RCTs was performed following the PRISMA statement. Data on triglycerides (TGs), total cholesterol (TC), HDL-C, and LDL-C were extracted. Relevant publications up to October 2020 were detected through searches in the PubMed/MEDLINE, Web of Science, Scopus, and Embase databases. Changes were reported as weighted mean differences (WMDs) and 95% CIs using random-effects models.

FINDINGS

Nine studies were selected, with a duration of intervention ranging from 2 and 12 months and a raloxifene dose of 60 to 120 mg/d. Studies were performed in healthy individuals and in those with disorders, such as osteoporosis, type 2 diabetes, and kidney disease required long-term hemodialysis. Overall, TG (WMD, -6.50 mg/dL; 95% CI, -34.18 to 21.20 mg/eL; P = 0.646), LDL-C (WMD, -17.86 mg/dL; 95% CI, -42.44 to 6.72 mg/dL; P = 0.154), and HDL-C (WMD, 2.35 mg/dL; 95% CI, -1.14 to 5.84 mg/dL; P = 0.187) levels did not change significantly after the administration of raloxifene. In contrast, TC levels decreased after raloxifene therapy (WMD, -6.59 mg/dL; 95% CI, -13.13 to -0.05 mg/dL; P = 0.048).

IMPLICATIONS

Raloxifene therapy decreased TC levels but did not alter TG, HDL-C, and LDL-C concentrations in elderly individuals. Regarding the LDL-C levels, although the finding lacked statistical significance, we believe that there was a mean reduction that deserves further clinical attention as much as TC.

A follow-up study of a randomized controlled study evaluating safety and efficacy of leuprorelin acetate every-3-month depot for 2 versus 3 or more years with tamoxifen for 5 years as adjuvant treatment in premenopausal patients with endocrine-responsive breast cancer

Background

Previously, we conducted the 5-year open-label, randomized controlled trial (RCT) of leuprorelin adjuvant therapy in post-operative premenopausal patients with endocrine-responsive breast cancer, which was a pilot study to investigate the optimal duration of leuprorelin treatment. Since, however, long-term outcomes became required for the adjuvant endocrine therapy, we performed this follow-up observation study.

Methods

Follow-up observation study was performed up to 10th year after randomization, continuing RCT to evaluate the efficacy and safety of leuprorelin every 3 months for ≥ 3 versus 2 years, with daily tamoxifen for 5 years. Primary endpoints were disease-free survival (DFS) and 2-year landmark DFS.

Results

Eligible patients (N = 222) were randomly assigned to receive leuprorelin for either 2 years (N = 112) or ≥ 3 years (N = 110) with tamoxifen. Leuprorelin treatment for ≥ 3 years versus 2 years provided no significant difference in DFS (HR 0.944, 95% CI 0.486–1.8392) or 2-year landmark DFS (N = 99 and 102 in 2-year and ≥ 3-year groups, HR 0.834, 0.397–1.753). In small, higher-risk subgroup (n = 17); however, 2-year landmark DFS in ≥ 3-year group was significantly longer (HR 0.095, 0.011–0.850) than that in 2-year group. The incidence of bone-related adverse events was around 5% in both groups.

Conclusions

Adjuvant leuprorelin treatment for ≥ 3 years with tamoxifen only showed similar efficacy and safety profiles to those for 2 years in analyses among all patients but suggested greater benefit in higher-risk patients. No new safety signal was identified for long-term leuprorelin treatment.

Trial registration number

Not applicable. This was an observational study.

Are sex discordant outcomes in COVID-19 related to sex hormones?

COVID-19 has a clear sex disparity in clinical outcome. Globally, infection rates between men and women are similar; however, men are more likely to have more severe disease and are more likely to die. The causes for this disparity are currently under investigation and are most likely multifactorial. Sex hormones play an important role in the immune response with estrogen seen as immune boosting and testosterone as immunosuppressing. Additionally, an important protease involved in viral entry, TMPRSS2, is regulated by androgens. Many observational and prospective studies are ongoing or initiating to further examine the role of sex hormones in SARS-CoV-2 infection and if modulation of them is a realistic treatment option.

ACE2: Its potential role and regulation in severe acute respiratory syndrome and COVID-19

COVID-19, a new disease caused by the 2019-novel coronavirus (SARS-CoV-2), has swept the world and challenged its culture, economy, and health infrastructure. Forced emergence to find an effective vaccine to immunize people has led scientists to design and examine vaccine candidates all over the world. Until a vaccine is developed, however, effective treatment is needed to combat this virus, which is resistant to all conventional antiviral drugs. Accordingly, more about the structure, entry mechanism, and pathogenesis of COVID-19 is required. Angiotensin-converting enzyme 2 (ACE2) is the gateway to SARS-CoV and SARS-CoV-2, so our knowledge of SARS-CoV-2 can help us to complete its mechanism of interaction with ACE2 and virus endocytosis, which can be interrupted by neutralizing small molecules or proteins. ACE2 also plays a crucial role in lung injury.

Effects of SULT1A1 Copy Number Variation on Estrogen Concentration and Tamoxifen-Associated Adverse Drug Reactions in Premenopausal Thai Breast Cancer Patients: A Preliminary Study

Tamoxifen is a pharmacological estrogen inhibitor that binds to the estrogen receptor (ER) in breast cells. However, it shows an estrogenic effect in other organs, which causes adverse drug reactions (ADRs). The sulfotransferase 1A1 (SULT1A1) enzyme encoded by the SULT1A1 gene is involved in estrogen metabolism. Previous research has suggested that the SULT1A1 copy number is linked with the plasma estradiol (E2) concentration. Here, a total of 34 premenopausal breast cancer patients, selected from the Thai Tamoxifen (TTAM) Project, were screened for their SULT1A1 copy number, plasma E2 concentration and ADRs. The mean age was 44.3±11.1 years, and they were subtyped as ER+/ progesterone receptor (PR) + (28 patients), ER+/ PR- (5 patients) and ER-/PR- (1 patient). Three patients reported ADRs, which were irregular menstruation (2 patients) and vaginal discharge (1 patient). Most (33) patients had two SULT1A1 copies, with one patient having three copies. The median plasma E2 concentration was 1,575.6 (IQR 865.4) pg/ml. Patients with ADRs had significantly higher plasma E2 concentrations than those patients without ADRs (p = 0.014). The plasma E2 concentration was numerically higher in the patient with three SULT1A1 copies, but this lacked statistical significance.

A randomized controlled study evaluating safety and efficacy of leuprorelin acetate every-3-months depot for 2 versus 3 or more years with tamoxifen for 5 years as adjuvant treatment in premenopausal patients with endocrine-responsive breast cancer

BACKGROUND

Luteinizing hormone-releasing hormone (LH-RH) agonists provide effective adjuvant treatment for premenopausal women with endocrine-responsive breast cancer. Here, we investigated appropriate treatment durations of an LH-RH agonist, leuprorelin.

METHODS

We conducted an open-label, randomized controlled pilot study to evaluate the safety and efficacy of leuprorelin subcutaneously administered every-3-months for 2 versus 3 or more, up to 5 years, together with daily tamoxifen for 5 years in premenopausal endocrine-responsive breast cancer patients. Primary endpoints were disease-free survival (DFS) and safety.

RESULTS

Eligible patients (N = 222) were randomly assigned to receive leuprorelin for either 2 years (N = 112) or 3 or more years (N = 110) with tamoxifen for 5 years after surgery. Leuprorelin treatment for 3 or more years provided no significant difference in DFS rate over 2 years: 94.1 versus 91.8 % at 144 weeks (3 years) after the second year (week 96) and 90.8 versus 90.4 % at the fifth year (week 240). The overall survival rate was 100 % for both groups during the third through fifth year study period. There were no significant differences in the incidence of adverse events (AEs) between the 2 groups: most AEs were rated grade 1 or 2.

CONCLUSIONS

Adjuvant leuprorelin treatment for 3 or more years with tamoxifen showed a survival benefit and safety profile similar to that for 2 years in premenopausal endocrine-responsive breast cancer patients. No new safety signal was identified for long-term leuprorelin treatment. Longer follow-up observation is needed to determine the optimal duration of leuprorelin treatment.

Tamoxifen stimulates calcitonin-producing thyroid C-cells and prevents trabecular bone loss in a rat model of androgen deficiency

Thyroid C-cells produce calcitonin (CT), a hypocalcemic hormone, that acts as an inhibitor of bone resorption. In this study, we investigated the effects of tamoxifen (TAM) as a selective estrogen receptor modulator on thyroid C-cells, trabecular bone and biochemical markers of bone metabolism in an animal model of androgen deficiency, represented by middle-aged orchidectomized (Orx) rats. Fifteen-month-old male Wistar rats were divided into: Orx and sham-operated (SO) groups. Rats from one Orx group were injected subcutaneously with TAM citrate (Orx + TAM; 0.3 mg kg(-1) b.w.), while the rats from SO and a second Orx group received vehicle alone, once a day for 3 weeks. The peroxidase-antiperoxidase method was applied for localization of CT in C-cells. Thyroid C-cells were morphometrically and ultrastructurally analyzed. An ImageJ image-processing program was used to measure bone histomorphometric parameters. Blood serum samples were analyzed for CT, osteocalcin (OC), calcium (Ca2+ ) and phosphorus (P). Urinary Ca2+ concentrations were measured. TAM treatment significantly increased thyroid C-cell volume (Vc ) and serum CT when compared with vehicle-treated Orx rats. Analysis of trabecular microarchitecture of the tibia showed that administration of TAM significantly increased cancellous bone area, trabecular thickness and trabecular number, whereas trabecular separation was significantly decreased compared with vehicle-treated Orx rats. Serum OC and urinary Ca2+ concentrations were significantly lower in comparison with the control Orx group. These results indicate that in our rat model of androgen deficiency, TAM stimulated calcitonin-producing thyroid C-cells and increased trabecular bone mass.

Anti-Mullerian hormone: determination of ovarian reserve in early breast cancer patients

Breast cancer is the most common invasive cancer in women of reproductive age. In young women, chemotherapy may induce amenorrhea: it is still uncertain how to assess menopausal status in these patients despite the importance of its definition for choosing appropriate endocrine treatment. In the development of sensitive biomarkers for fertility and ovarian reserve, anti-Müllerian hormone (AMH) is considered a promising marker of ovarian reserve. The clearest data regarding a clinical use of AMH are related to the measurement of the ovarian pool in women who undergo IVF: the available data, also in breast cancer patients, seem to suggest that AMH measurement, before gonadotropin administration, can be a useful marker for the prediction of women at risk for poor-response or no response to ovarian stimulation. The utility of AMH as a potential marker of chemotherapy-induced ovarian follicular depletion and an early plasma marker of chemotherapy-induced gonadal damage has been evaluated both in young women after treatment for cancer in childhood and in young survivors of hematological malignancies and solid tumors. Several studies have demonstrated a potential utility of AMH, inhibin, or follicle-stimulating factor as biomarkers predicting infertility risk in breast cancer patients, but the studies conducted so far are not conclusive. Further studies are needed in order to define the regimen-specific action of chemotherapy on AMH levels, the percentage of post-treatment recovery of plasma levels of the hormone, and the relationship between menopausal status and AMH.

Age, photoperiod and estrogen dependent variations in the shell gland and the expression of AVT in the ovary of Japanese quail

Present work was undertaken to describe (i) age dependent (prepuberal-3, 4, 5 and 6 weeks old, puberal and actively laying 8 and 12 weeks old and aged 78 weeks old) (ii) photoperiodic response dependent (photosensitive and photorefractory) and sex steroid dependent (estradiol benzoate and its antagonist tamoxifen treated) variation in the ovary and shell gland activity of Japanese quail (Coturnix coturnix japonica). Further, in view of the role of neurohypophysial peptide arginine vasotocin (AVT) in many physiological processes including age/reproduction related oviposition, expression of ir-AVT was also monitored in the ovary of quail. All the parameters associated with histodifferentiation increased rapidly during the developing stages followed by a decrease in old age, which also increased in reproductively quiescent photorefractory birds following estradiol treatment and decreased in reproductively active photosensitive quail following tamoxifen treatment. Using AVT-specific antibody, expression of immunoreactive AVT (ir-AVT) observed in the ovary of photosensitive quail was not detected in the photorefractory quail. However, administration of estrogen in the photorefractory quail stimulated the growth and activity of ovary and shell gland also resulted in the expression of ovarian ir-AVT. On the other hand, tamoxifen eliminated the localization of ir-AVT in the ovary of photosensitive quail in addition to a decrease in the shell gland protein and alkaline phosphatase activity. It is concluded that estrogen not only affects the growth and differentiation of ovary and oviduct including shell gland but also regulates the expression of ovarian AVT. It is also suggested that in addition to reported paracrine effect of AVT in the shell gland of Japanese quail for oviposition, ovarian AVT may also affect ovarian function (ovulation), and in part, this regulation is estrogen dependent.

Low-dose dietary genistein negates the therapeutic effect of tamoxifen in athymic nude mice

The present study examined the effect of dietary genistein, a soy isoflavone, on breast cancer patients who take tamoxifen, an antiestrogen treatment, using a preclinical model. The interaction of various doses of genistein with tamoxifen on the growth of estrogen receptor-positive breast cancer MCF-7 cells was investigated by subcutaneously injecting MCF-7 cells into the flank of ovariectomized athymic mice. Animals were randomized into eight experimental groups with 10-13 mice per group: control (C), estrogen (E) (0.08 mg E implant), tamoxifen (T) (3 mg T implant), estrogen + tamoxifen (E + T), tamoxifen + 500 p.p.m. genistein (T + G500), estrogen + tamoxifen + 250 p.p.m. genistein (E + T + G250), estrogen + tamoxifen + 500 p.p.m. genistein (E + T + G500) and estrogen + tamoxifen + 1000 p.p.m. genistein (E + T + G1000). Treatment of tamoxifen significantly reduced the estrogen-induced MCF-7 tumor prevalence and tumor size. This inhibitory effect of tamoxifen was significantly negated by the low doses of dietary genistein (250 and 500 p.p.m.), whereas the 1000 p.p.m. genistein did not have the same effect. Cells harvested from tamoxifen-treated tumors retained estrogen responsiveness of their progenitor MCF-7 cells, indicating that the abrogating effect of genistein on tamoxifen-treated tumor growth was not caused by a diminished tamoxifen response but directly by genistein. The low doses of dietary genistein abrogated the inhibitory effect of tamoxifen potentially by acting on the tumor cell proliferation/apoptosis ratio and the messenger RNA (mRNA) expression of cyclin D1 in addition to regulating the mRNA expression of progesterone receptor. Therefore, data from the current study suggest that caution is warranted regarding the consumption of dietary genistein by breast cancer patients while on tamoxifen therapy.

Defining ovarian failure in amenorrheic young breast cancer patients

At present, there is no gold standard test for the investigation of ovarian function in pre-menopausal breast cancer patients who develop amenorrhea after chemotherapy. Clinical, biochemical and biophysical investigations continue to be utilized in clinical practice, despite concerns regarding their predictive value for menopause. The resulting uncertainty about a woman's actual menopausal status has important consequences for patient management. These include choice of appropriate endocrine therapy, assessment of residual ovarian function and its effect on breast cancer recurrence, fertility issues and the prediction of the likelihood of conception. It is hoped that the development of novel surrogates may allow clinicians to more accurately assess menopausal status and thereby facilitate tailored and individualised therapy for this common group of patients.

Associations between tamoxifen, estrogens, and FSH serum levels during steady state tamoxifen treatment of postmenopausal women with breast cancer

Background

The cytochrome P450 (CYP) enzymes 2C19, 2D6, and 3A5 are responsible for converting the selective estrogen receptor modulator (SERM), tamoxifen to its active metabolites 4-hydroxy-tamoxifen (4OHtam) and 4-hydroxy-N-demethyltamoxifen (4OHNDtam, endoxifen). Inter-individual variations of the activity of these enzymes due to polymorphisms may be predictors of outcome of breast cancer patients during tamoxifen treatment. Since tamoxifen and estrogens are both partly metabolized by these enzymes we hypothesize that a correlation between serum tamoxifen and estrogen levels exists, which in turn may interact with tamoxifen on treatment outcome. Here we examined relationships between the serum levels of tamoxifen, estrogens, follicle-stimulating hormone (FSH), and also determined the genotypes of CYP2C19, 2D6, 3A5, and SULT1A1 in 90 postmenopausal breast cancer patients.

Methods

Tamoxifen and its metabolites were measured by liquid chromatography-tandem mass spectrometry. Estrogen and FSH levels were determined using a sensitive radio- and chemiluminescent immunoassay, respectively.

Results

We observed significant correlations between the serum concentrations of tamoxifen, N-dedimethyltamoxifen, and tamoxifen-N-oxide and estrogens (p < 0.05). The genotype predicted CYP2C19 activity influenced the levels of both tamoxifen metabolites and E1.

Conclusions

We have shown an association between tamoxifen and its metabolites and estrogen serum levels. An impact of CYP2C19 predicted activity on tamoxifen, as well as estrogen kinetics may partly explain the observed association between tamoxifen and its metabolites and estrogen serum levels. Since the role of estrogen levels during tamoxifen therapy is still a matter of debate further prospective studies to examine the effect of tamoxifen and estrogen kinetics on treatment outcome are warranted.

Reproductive steroid hormones and recurrence-free survival in women with a history of breast cancer

Epidemiologic studies fairly consistently show in postmenopausal women that reproductive steroid hormones contribute to primary breast cancer risk, and this association is strongly supported by experimental studies using laboratory animals and model systems. Evidence linking sex hormone concentrations with risk for recurrence in women diagnosed with breast cancer is limited; however, beneficial effects of antiestrogenic therapy on recurrence-free survival suggest that these hormones affect progression and risk for recurrence. This study examined whether baseline serum concentrations of estradiol, testosterone, and sex hormone binding globulin were associated with recurrence-free survival in a nested case-control cohort of women from a randomized diet trial (Women's Healthy Eating and Living Study) who were followed for >7 years after diagnosis. In 153 case-control pairs of perimenopausal and postmenopausal women in this analysis, total estradiol [hazard ratio (HR), 1.41 per unit increase in log concentration; 95% confidence interval (95% CI), 1.01-1.97], bioavailable estradiol (HR, 1.26; 95% CI, 1.03-1.53), and free estradiol (HR, 1.31; 95% CI, 1.03-1.65) concentrations were significantly associated with risk for recurrence. Recurred women had an average total estradiol concentration that was double that of nonrecurred women (22.7 versus 10.8 pg/mL; P = 0.05). Testosterone and sex hormone binding globulin concentrations did not differ between cases and controls and were not associated with risk for recurrence. Although genetic and metabolic factors likely modulate the relationship between circulating sex hormones and risk, results from this study provide evidence that higher serum estrogen concentration contributes to risk for recurrence in women diagnosed with early stage breast cancer.

NADPH-dependent metabolism of 17beta-estradiol and estrone to polar and nonpolar metabolites by human tissues and cytochrome P450 isoforms

The endogenous estrogens, 17beta-estradiol (E(2)) and estrone (E(1)), undergo extensive metabolism in animals and humans, and a large number of their hydroxylated and keto metabolites have been identified in biological samples. The formation of most of the oxidative estrogen metabolites is catalyzed by cytochrome P450 (CYP) enzymes. Precise knowledge of the CYP-mediated formation of these metabolites, particularly those with unique biological activities (e.g., 4-hydroxy-E(2), 16alpha-hydroxy-E(1), 15alpha-hydroxy-E(2), 16-epiestriol, and 2-methoxyestradiol) in human liver and extrahepatic target tissues and cells, would add significantly to our understanding of the diverse biological functions that are associated with endogenous estrogens. In this article, we review recent results on the NADPH-dependent metabolism of endogenous estrogens to polar (hydroxylated and keto) metabolites as well as to nonpolar metabolites by human tissues and recombinant human CYP isoforms. The available data show that a large number of polar and nonpolar metabolites of E(2) and E(1) are formed by human tissues, and a variety of human CYP isoforms are involved in the NADPH-dependent formation of polar as well as nonpolar estrogen metabolites. These enzymes have varying degrees of catalytic activity and distinct regioselectivity.

Hot flashes, core body temperature, and metabolic parameters in breast cancer survivors

OBJECTIVE

To examine core body temperature, energy expenditure, and respiratory quotient among breast cancer survivors experiencing hot flashes and compare these data to published studies from healthy women.

DESIGN

In an observational study, nine breast cancer survivors with daily hot flashes who met specified criteria spent 24 hours in a temperature- and humidity-controlled whole-room indirect calorimeter (ie, metabolic room). Demographic and disease/treatment information were obtained and the following were measured: hot flashes via sternal skin conductance monitoring (sampled every second); core body temperature via an ingested radiotelemetry pill (sampled every 10 seconds); and energy expenditure and respiratory quotient via a whole-room indirect calorimeter (calculated every minute).

RESULTS

Circadian analysis of core temperature indicated wide variability with disrupted circadian rhythm noted in all women. Core temperature began to rise 20 minutes pre-flash to 7 minutes pre-flash (0.09 degrees C increase). Increases in energy expenditure and respiratory quotient increased with each hot flash.

CONCLUSIONS

Findings are comparable to published data from healthy women and warrant replication in larger, more diverse samples of women treated for breast cancer.

Effects of a high-fiber, low-fat diet intervention on serum concentrations of reproductive steroid hormones in women with a history of breast cancer

PURPOSE

Diet intervention trials are testing whether postdiagnosis dietary modification can influence breast cancer recurrence and survival. One possible mechanism is an effect on reproductive steroid hormones.

PARTICIPANTS AND METHODS

Serum reproductive steroid hormones were measured at enrollment and 1 year in 291 women with a history of breast cancer who were enrolled onto a randomized, controlled diet intervention trial. Dietary goals for the intervention group were increased fiber, vegetable, and fruit intakes and reduced fat intake. Estradiol, bioavailable estradiol, estrone, estrone sulfate, androstenedione, testosterone, dehydroepiandrosterone sulfate, follicle-stimulating hormone, and sex hormone-binding globulin were measured.

RESULTS

The intervention (but not the comparison) group reported a significantly lower intake of energy from fat (21% v 28%), and higher intake of fiber (29 g/d v 22 g/d), at 1-year follow-up (P <.001). Significant weight loss did not occur in either group. A significant difference in the change in bioavailable estradiol concentration from baseline to 1 year in the intervention (-13 pmol/L) versus the comparison (+3 pmol/L) group was observed (P <.05). Change in fiber (but not fat) intake was significantly and independently related to change in serum bioavailable estradiol (P <.01) and total estradiol (P <.05) concentrations.

CONCLUSION

Results from this study indicate that a high-fiber, low-fat diet intervention is associated with reduced serum bioavailable estradiol concentration in women diagnosed with breast cancer, the majority of whom did not exhibit weight loss. Increased fiber intake was independently related to the reduction in serum estradiol concentration.

Hot flashes and related outcomes in breast cancer survivors and matched comparison women

PURPOSE/OBJECTIVES

To compare the hot flash symptom experience and related outcomes between breast cancer survivors and healthy women.

DESIGN

Descriptive, cross-sectional, comparative study.

SETTING

Southeastern university medical center.

SAMPLE

69 of 207 breast cancer survivors contacted via a tumor registry and 63 age-matched healthy female volunteers. Survivors were a mean of 57 years and a mean of 39 months postdiagnosis.

METHODS

Mailed survey included a demographic, disease, and treatment information form; a gynecologic history form; a two-day, prospective, hot flash diary; a detailed hot flash questionnaire; mood and affect scales; and the Hot Flash-Related Daily Interference Scale.

MAIN RESEARCH VARIABLES

Hot flashes, mood, affect, interference with daily activities, and overall quality of life.

FINDINGS

Breast cancer survivors had hot flashes that were significantly more frequent, severe, distressing, and of greater duration. Breast cancer survivors were less likely to be using hormone replacement and more likely to have tried nonhormonal prescription interventions in the past, but reported significantly less effectiveness from hot flash treatments. Breast cancer survivors with severe hot flashes reported significantly greater mood disturbance; higher negative affect; more interference with daily activities, including sleep, concentration, and sexuality; and poorer overall quality of life in comparison to breast cancer survivors with no hot flashes to mild hot flashes. Hot flash quality and triggers were not significantly different between groups. No clear temporal pattern of hot flashes emerged.

CONCLUSIONS

Hot flashes are a significant problem for breast cancer survivors, even for those who are naturally postmenopausal (i.e., did not undergo menopause as a result of surgery or the effects of chemotherapy). Hot flashes remained fairly stable over time and did not diminish in frequency, severity, or associated distress.

IMPLICATIONS FOR NURSING

The findings guide the assessment of the uniqueness of the problem of hot flashes experienced by breast cancer survivors and help define outcomes to address in clinical practice or include in future hot flash intervention research.

NADPH-dependent metabolism of estrone by human liver microsomes

We characterized the NADPH-dependent metabolism of estrone (E1) by liver microsomes of 21 male and 12 female human subjects. The structures of 11 hydroxylated or keto metabolites of E1 formed by human liver microsomes were identified by chromatographic and mass spectrometric analyses. 2-Hydroxylation of E1 was the dominant metabolic pathway with all human liver microsomes tested. E1 is more prone to form catechol estrogens (particularly 4-OH-E1) than 17beta-estradiol (E2) and the average ratio of E1 4-hydroxylation to 2-hydroxylation (0.24) was slightly higher than the ratio of E2 4- to 2-hydroxylation (0.20, P < 0.001). An unidentified monohydroxylated E1 metabolite (y-OH-E1) was found to be one of the major metabolites formed by human liver microsomes of both genders. 6beta-OH-E1, 16alpha-OH-E1, and 16beta-OH-E1 were also formed in significant quantities. 16alpha-hydroxylation was not a major pathway for E1 metabolism. The overall profiles for the E1 metabolites formed by male and female human liver microsomes were similar, and their average rates were not significantly different. Hepatic CYP3A4/5 activity in both male and female liver microsomes correlated strongly with the rates of formation of several hydroxyestrogen metabolites. The dominant role of hepatic CYP3A4 and CYP3A5 in the formation of these hydroxyestrogen metabolites was further confirmed by incubations of human CYP3A4 or CYP3A5 with [3H]E1 and NADPH. Notably, human CYP3A5 has very high relative activity for E1 4-hydroxylation, exceeding its activity for E1 2-hydroxylation by approximately 100%. It will be of interest to determine the potential biological functions associated with any of the E1 metabolites identified in our present study.

Combination endocrine therapy in the management of breast cancer

Combination endocrine therapy has long been sought after as a means to better treat breast cancer. Agents that suppress estrogen production are given with agents that suppress estrogenic activity at the cellular level. Historically, these combinations have resulted in initial improvements in response rates, but relapse-free and overall survival were not significantly improved. Also, the increased toxicity seen with these regimens was limiting. New endocrine therapies with more potent activity and less toxicity have led to a resurgence of this idea in the management of breast cancer. Complete estrogen blockade has been compared with single-agent treatments in many different settings. The endocrine effects of this type of therapy are intriguing, but apparently do not readily predict a clinical advantage. The combination of an aromatase inhibitor and an antiestrogen, despite pharmacokinetic interactions, may prove to be beneficial. Results from ongoing trials are eagerly awaited to further address this question in postmenopausal breast cancer patients. For premenopausal breast cancer patients the options are more complex. Clinical outcomes with leutinizing hormone releasing hormone (LHRH) agonists plus aromatase inhibitors are limited to very small phase II studies and are not clearly superior to single-agent therapy. Clinical data in the metastatic setting with premenopausal patients favor the use of an LHRH agonist with tamoxifen over the use of an LHRH agonist alone. However, a similar comparison with tamoxifen alone is lacking with only one trial including this as a treatment arm. Adjuvant therapy with this combined endocrine approach (LHRH agonist plus antiestrogen) has been more extensively studied, but lacks crucial comparisons necessary for making complex treatment decisions. Hopefully, through investigative diligence and ingenuity this issue can be adequately understood. However, many exciting new agents are on the horizon that offer hope to further advance the progress made to date although further confounding the questions already answered.

High dehydroepiandrosterone-sulfate predicts breast cancer progression during new aromatase inhibitor therapy and stimulates breast cancer cell growth in tissue culture: a renewed role for adrenalectomy

BACKGROUND

Stage IV hormone-sensitive breast cancer is often treated with aromatase inhibitors (anastrozole, letrozole, exemestane), which block the conversion of dehydroepiandrosterone (DHEA) to estrone and estradiol. This is intended to obviate the need for steroid replacement and antiquate adrenalectomy.

METHODS

Patients who underwent oophorectomy and were being treated with new aromatase inhibitor therapy received serial measurements of serum estrone, estradiol, and DHEA-sulfate (DHEA-S). Steroid values during responsive and progressive phases of disease were compared. In vitro, human breast cancer cell lines T-47D (estrogen-receptor and progesterone-receptor positive) and HCC 1937 (estrogen-receptor and progesterone-receptor negative) were treated with DHEA-S. Proliferation rates were measured by colorimetric assay.

RESULTS

Disease in 12 of the 19 patients progressed. DHEA-S was less than 89 microg/dL in patients during the responsive phase and more than or equal to 89 microg/dL during disease progression, with 1 exception (P < .0005). Estrone and estradiol remained suppressed. After disease progression, the condition of 9 patients stabilized with aminoglutethimide therapy (n = 8) or adrenalectomy (n = 1), and their DHEA-S levels were reduced to less than 89 microg/dL. In vitro, elevated DHEA-S induced cell proliferation in T-47D cells.

CONCLUSIONS

DHEA-S levels more than or equal to 89 microg/dL predicted disease progression in states of low estrogen. Tissue culture results supported the role of DHEA-S as an estrogenic agent. Oophorectomies with either aminoglutethimide therapy or adrenalectomy were effective remedies for breast cancer progression due to high DHEA-S.

Circadian rhythm of objectively recorded hot flashes in postmenopausal breast cancer survivors

OBJECTIVE

Similar to the circadian rhythm of core body temperature, hot flashes have been found to exhibit a circadian rhythm in healthy, naturally postmenopausal women, with a peak in frequency at 18:25 h. However, to date, no studies have evaluated whether this same pattern is found among breast cancer survivors reporting hot flashes.

DESIGN

Daily hot flash frequencies were measured among 21 postmenopausal breast cancer survivors using validated 24-h sternal skin conductance monitoring.

RESULTS

Hot flashes were noted in all women, ranging in frequency from 1 to 30 per 24-h period. A majority of the sample (86%) experienced > or = 1 nighttime hot flash, with 48% exhibiting > or = 3 but < or = 7 nighttime hot flashes. For the total sample, a modest circadian rhythm was noted with a peak in hot flash frequency occurring at 16:10 h. However, significant variability was observed across individual women, and, as a whole, breast cancer survivors demonstrated distorted to obliterated rhythms.

CONCLUSIONS

Data suggest that hot flashes in postmenopausal breast cancer survivors do not follow the same circadian pattern as previously seen in healthy, naturally postmenopausal women. Findings have implications for (1) understanding the potential for sleep disturbances and fatigue in breast cancer survivors experiencing hot flashes, and (2) future research examining circadian rhythms of core body temperature and hot flashes in breast cancer survivors.

Complete estrogen blockade for the treatment of metastatic and early stage breast cancer

Complete estrogen blockade has long been sought as a more effective means of controlling breast cancer compared with single agent endocrine therapy. This approach may be accomplished through the use of agents which reduce estrogen production combined with agents that prevent the activity of estrogen at the cellular level. For prostate cancer, another hormonally responsive malignancy, this approach has not been successful at improving survival compared with that achieved with single agent therapy. Preclinical information is contradictory for many promising combinations and may not reflect the true nature of in vivo interaction between agents. For premenopausal patients with metastatic breast cancer, the combination of a luteinising hormone-releasing hormone (LHRH) agonist and tamoxifen is clearly effective, but whether the combination is more effective than either single agent is still controversial. Similar response rates and overall survival were reported with goserelin or goserelin plus tamoxifen by Jonat et al. in 1 randomised, prospective study, but the addition of tamoxifen improved time to progression. A second trial comparing buserelin plus tamoxifen with either single agent reported superior efficacy in terms of response rates, disease-free survival and overall survival with combination therapy. A meta-analysis of 4 randomised trials making similar comparisons, demonstrated significant improvement in median overall survival, progression-free survival, response rate, and duration of response with the combination of a LHRH agonist (goserelin or buserelin) and tamoxifen in premenopausal breast cancer patients with metastatic disease. For postmenopausal women with metastatic breast cancer, the addition of an aromatase inhibitor to tamoxifen has yet to be prospectively compared to single agent therapy. Use of endocrine combinations in the treatment of early stage breast cancer is under investigation. Preliminary results of some of the ongoing adjuvant therapy trials indicate that the combination of a LHRH agonist and tamoxifen may have similar efficacy to cyclophosphamide, methotrexate, and fluorouracil chemotherapy in premenopausal women with estrogen receptor-positive tumour. Addition of LHRH agonist therapy in premenopausal patients with estrogen receptor-positive tumour who had maintained the ovarian function following chemotherapy [cyclophosphamide, doxorubicin (adriamycin), fluorouracil, and tamoxifen], also led to a reduction in the risk of recurrence. These studies have identified a sub-population of patients who may benefit from the addition of combination endocrine therapy. Overall, the issue is quite complex and the data from many ongoing trials are still awaited with anticipation to further delineate the role of complete estrogen deprivation in this disease.

Special considerations in breast cancer risk and survival

Experimental and clinical evidence suggests that breast neoplasia appears to be a hormone-dependent process that may also be influenced by dietary factors in many women. Conflicting reports on the relationship between exogenous hormones and the development, progression, and recurrence of breast cancer are critically examined in this report. The absolute breast cancer risk associated with either hormone replacement therapy or oral contraceptive use has not been clearly defined. Data from some large prospective studies have actually documented lower mortality rates for women taking hormone replacement compared with those for women who did not have hormone replacement therapy. In this regard, age, duration of use, and preexisting breast cancer risk factors must be taken into account. Although the results of two major prospective clinical trials addressing the role of timing of surgery within the menstrual cycle are forthcoming, the majority of studies have found no consistent association between timing of surgery and breast cancer survival. Recently reported prospective randomized data showing that selective-estrogen-receptor-modulators can act as effective chemoprevention agents in women at increased risk for breast cancer development are presented. Finally, information regarding the effect of dietary manipulation on breast cancer risk and survival is reviewed.