Estrogen plus progestin and risk of benign proliferative breast disease

Hormone therapy in women with benign breast disease - What little is known and suggestions for clinical implementation

Benign breast disease encompasses a spectrum of lesions within the breast. While some lesions pose no increase in risk, others may elevate the likelihood of developing breast cancer by four- to five-fold. This necessitates a personalized approach to screening and lifestyle optimization for women. The menopausal transition is a critical time for the development of benign breast lesions. Increased detection can be attributed to the heightened precision and utilization of screening mammography, with or without the use of supplemental imaging. While it is widely acknowledged that combined hormone therapy involving estrogen and progesterone may elevate the risk of breast cancer, data from the Women's Health Initiative (WHI) indicates that estrogen-alone therapies may actually reduce the overall risk of cancer. Despite this general understanding, there is a notable gap in information regarding the impact of hormone therapy on the risk profile of women with specific benign breast lesions. This review comprehensively examines various benign breast lesions, delving into their pathophysiology and management. The goal is to enhance our understanding of when and how to judiciously prescribe hormone therapy, particularly in the context of specific benign breast conditions. By bridging this knowledge gap, the review provides valuable insights into optimizing healthcare strategies for women with benign breast disease, and offers a foundation for more informed decision-making regarding hormone therapy.

Growth of a Nipple Adenoma After Estrogen Replacement Therapy

A nipple adenoma is an epithelial tumor of the lactiferous ducts, typically affecting women aged 50-60 years old. This case report discusses a 52-year-old woman who developed a papillary adenoma of the right nipple after initiating oral estrogen replacement therapy (ERT) for perimenopausal symptoms. A 4 mm punch biopsy and subsequent immunohistochemistry stain revealed the proliferation of ductal structures consistent with a papillary adenoma and tumor cells expressing estrogen receptors (ER) and progesterone receptors (PR). Despite their benign nature, nipple adenomas may exhibit alterations in immunophenotype, including ER and PR expression, which could lead to potential tumor growth in women undergoing these treatments. This case describes the first reported growth of a nipple adenoma in the context of estrogen replacement therapy, highlighting a potential risk of hormone therapy in promoting hyperproliferation of benign tumors such as nipple adenomas. When utilizing ERT, it is important to weigh the potential advantages and risks, as its application in the management of vasomotor symptoms during menopause may increase the risk of both breast cancer and benign proliferative breast diseases. These considerations underscore the need for individualized therapy when approaching perimenopausal and postmenopausal care.

An Interesting Imaging Presentation of a Common Benign Entity: Fibrocystic Changes in a Postmenopausal Patient

Fibrocystic changes (FCCs) are common, often benign, breast lesions characterized by adenosis, fibrosis, and cyst formation. These changes are believed to be associated with fluctuating hormone levels and are predominantly found in premenopausal women due to higher levels of estrogen. Certain conditions that cause hormonal imbalances, such as polycystic ovarian syndrome, have also been associated with an increased risk of FCCs. FCCs can occur in postmenopausal women on hormonal replacement therapy but are otherwise extremely rare. Although this condition is primarily considered benign, complex cysts presenting in a rare demographic warrant further evaluation beyond screening mammograms to exclude the possibility of malignancy. In this paper, we present the case of new FCCs in a postmenopausal woman and explore the radiology, histology, carcinogenic potential, treatment options, and potential contributing factors of the condition.

The relationship between using estrogen and/or progesterone and the risk of mammary gland hyperplasia in women: a meta-analysis

BACKGROUND

As reported that the usage of estrogen and/or progesterone increases the risk of mammary gland hyperplasia (MGH) with conflicting results. Therefore, we conducted a meta-analysis to higher elucidate the relationship between hormones and MGH.

METHOD

PubMed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, and Wan-fang database were searched for studies until April 28, 2021.

RESULTS

Nine related studies were included in the present meta-analysis. We found that the usage of estrogen and/or progesterone had a significant association with increasing the risk of MGH (RR = 1.56, 95% CI: 1.13-2.15, p = .000). The subgroup results showed that the risk of MGH increased in the Mix population (RR = 1.72, CI: 1.58-1.88, p < .001) but no significant difference in the Asian population. Meanwhile, as for using estrogen plus progesterone (EPP) and postmenopausal women the risk of MGH, respectively, increased (RR = 1.74, CI: 1.22-2.47, p = .002) and (RR = 1.75, CI: 1.24-2.47, p = .001) but no significant different for using estrogen alone and premenopausal women.

CONCLUSIONS

This study findings indicated that using estrogen and/or progesterone might increase the risk of MGH in premenopausal and postmenopausal women.

Physical activity and risk of benign proliferative epithelial disorders of the breast, in the Women's Health Initiative

BACKGROUND

Recreational physical activity (PA) has been shown to be inversely associated with breast cancer risk. However, the association of recreational PA with benign proliferative epithelial disorders (BPED) of the breast, conditions associated with increased risk of breast cancer, has not been adequately studied.

METHODS

We used data from an ancillary study of benign breast disease conducted among the 68 132 postmenopausal women (aged 50-79 at recruitment) participating in the Women's Health Initiative randomized clinical trials. All clinical trial participants underwent annual or biennial mammogram screening. During the follow-up, for women who reported breast biopsies but were cancer free, the associated histological sections were obtained and subjected to standardized central pathology review. Self-reported recreational PA at baseline (n = 61 684) and at 3 years of the follow-up (n = 55 923) were quantified as metabolic equivalents [MET]-h/week. There were 1624 confirmed BPED cases during an average follow-up time of 7.7 years. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Higher average PA over 4 years was associated with lower risk of non-atypical BPED (P-trend = 0.02). There was a 6% lower risk of non-atypical BPED for every 5 MET-h/week increase between baseline and year 3 (HR = 0.94, 95% CI 0.89-0.99). Compared with women who remained inactive (PAbaseline and PAyear3 <9 MET-h/week), those who became active (PAbaseline<9 MET-h/week to PAyear3 ≥9 MET-h/weekee), remained active (PAbaseline and PAyear3 ≥9 MET-h/week), or decreased activity (PAbaseline ≥9 MET-h/week to PAyear3 <9 MET-h/week) had lower BPED risk.

CONCLUSIONS

Recreational physical activity after menopause was associated with lower BPED risk among postmenopausal women.

Characterization of Benign Breast Diseases and Association With Age, Hormonal Factors, and Family History of Breast Cancer Among Women in Sweden

IMPORTANCE

Benign breast diseases (BBDs) are common and associated with breast cancer risk, yet the etiology and risk of BBDs have not been extensively studied.

OBJECTIVE

To investigate the risk of BBDs by age, hormonal factors, and family history of breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study assessed 70 877 women from the population-based Karolinska Mammography Project for Risk Prediction of Breast Cancer (KARMA) who attended mammographic screening or underwent clinical mammography from January 1, 2011, to March 31, 2013, at 4 Swedish hospitals. Participants took part in a comprehensive questionnaire on recruitment. All participants had complete follow-up through high-quality Swedish national registers until December 31, 2015. Pathology medical records on breast biopsies were obtained for the participants, and BBD subtypes were classified according to the latest European guidelines. Analyses were conducted from January 1 to July 31, 2020.

EXPOSURES

Hormonal risk factors and family history of breast cancer.

MAIN OUTCOMES AND MEASURES

For each BBD subtype, incidence rates (events per 100 000 person-years) and multivariable Cox proportional hazards ratios (HRs) with time-varying covariates were estimated between the ages of 25 and 69 years.

RESULTS

A total of 61 617 women within the mammographic screening age of 40 to 69 years (median age, 53 years) at recruitment with available questionnaire data were included in the study. Incidence rates and risk estimates varied by age and BBD subtype. At premenopausal ages, nulliparity (compared with parity ≥3) was associated with reduced risk of epithelial proliferation without atypia (EP; HR, 0.62; 95% CI, 0.46-0.85) but increased risk of cysts (HR, 1.38; 95% CI, 1.03-1.85). Current and long (≥8 years) oral contraceptive use was associated with reduced premenopausal risk of fibroadenoma (HR, 0.65; 95% CI, 0.47-0.90), whereas hormone replacement therapy was associated with increased postmenopausal risks of epithelial proliferation with atypia (EPA; HR, 1.81; 95% CI, 1.07-3.07), fibrocystic changes (HR, 1.60; 95% CI, 1.03-2.48), and cysts (HR, 1.98; 95% CI, 1.40-2.81). Furthermore, predominantly at premenopausal ages, obesity was associated with reduced risk of several BBDs (eg, EPA: HR, 0.31; 95% CI, 0.17-0.56), whereas family history of breast cancer was associated with increased risk (eg, EPA: HR, 2.11; 95% CI, 1.48-3.00).

CONCLUSIONS AND RELEVANCE

These results suggest that the risk of BBDs varies by subtype, hormonal factors, and family history of breast cancer and is influenced by age. Better understanding of BBDs is important to improve the understanding of benign and malignant breast diseases.

Progestins and the Risk of Breast Cancer

OBJECTIVES

The present paper aims to investigate the effects of both progesterone and progestin treatment mainly related to the occurrence of breast cancer in women.

MATERIALS AND METHODS

Extensive systematic bibliographic review of Greek and International articles was conducted through the electronic databases Pubmed, Cinahl, Uptodate, and Google Scholar for the identification of articles related to progesterone, progestins and breast cancer treatment.

RESULTS

Hormone therapy with the use of estrogen alone presents a small increased risk or does not present at all an increased risk of breast cancer. With ORs in some studies below 1.0 in current users for 3 plus years and safe option until 7 years, while in other studies the risk was increased with the ORs 1.29. However, the use of estrogen in combination with progestogens, depending on the type of progestogens, shows an increased risk of breast cancer, with the ORs to vary between 1.14- 2.38 from 3 to 5 years and is inversely proportional to the time of its use. This risk varies depending on the combination of the preparations. Other factors that are associated with breast cancer risk when receiving hormone therapy are the years that hormone therapy is taken, directly proportional to the risk. At higher risk are older women, women with low body mass index in menopause (BMI <25kg/m²) and women with increased mammographic breast density. Continued use of hormone therapy is associated with an increased risk for breast cancer compared to sequential. The risk became visible sooner to women who used in the past hormone therapy and were using it again. Starting hormone therapy in the immediate postmenopausal period also increased the risk for breast cancer. Hormone therapy was associated with tumors with positive estrogen and progesterone receptors, and also the lobular histological type was associated with its use. Tibolone use was associated with an increased risk.

Effects of progestogens used in menopause hormone therapy on the normal breast and benign breast disease in postmenopausal women

Hormone replacement therapy in menopause is used to improve climacteric syndrome in women whose quality of life is affected. However, given the wide variety of progestogens available, it is important to evaluate their differential benign changes (radiological, cellular, and clinical) on the breast. This review aimed to determine the different benign changes of progestogens used in postmenopausal combined hormone therapy on the breast (radiological, cellular, and clinical), in women without mammary pathology, in order to establish their safety profile. A systematic review of the literature was carried out with a balanced search strategy for the identification of relevant references in the MEDLINE, BVSalud, EMBASE, ProQuest, and Cochrane databases until November 2019. The search terms used were 'menopause' or 'hormonal replacement therapy' or 'progestins' or 'estrogen' or 'mastodynia' or 'benign breast disease' or 'mammography'. Data were collected from the 'eligible' articles by two researchers (ARF and SHA), and possible discrepancies in inclusion were resolved by consensus. A total of 1886 articles were identified; 60 full-text articles were reviewed, and 17 articles that met the inclusion criteria were included for the qualitative analysis. In conclusion, combined hormone replacement therapy is associated with benign effects on the breast, such as mastodynia and increased mammographic density.

Association Between the Presence of Female-Specific Tumors and Aggressive Clinicopathological Features in Papillary Thyroid Cancer: A Retrospective Analysis of 9,822 Cases

Objective

To investigate the association between the presence of female-specific tumors and aggressive clinicopathological features in papillary thyroid cancer (PTC).

Methods

This study retrospectively analyzed 9,822 female cases between June 2008 and December 2017. Odds ratios and corresponding 95% confidence intervals were calculated. Findings were stratified by age and body mass index (BMI) in different models.

Results

1443/9822 (14.7%) patients with PTC had a female-specific tumor. Presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter (adjusted OR = 1.446, 95% CI 1.136–1.840, P = 0.003), but a protective factor against extrathyroidal extension of PTC (adjusted OR = 0.650, 95%CI 0.500–0.845, P = 0.001). Presence of a benign uterine mass was an independent risk factor for multifocal PTC (adjusted OR = 1.305, 95%CI 1.113–1.531, P = 0.001). Analyses stratified by age and BMI revealed the presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter in patients aged <36 years (adjusted OR = 1.711, 95% CI 1.063–2.754, P = 0.027), and a protective factor against extrathyroidal extension of PTC in patients aged ≥36 - <42 years (OR adjusted = 0.533, 95% CI 0.302–0.941, P = 0.030) or with a BMI ≥ 23.4 kg/m² (BMI ≥ 23.4 to < 25.7 kg/m², adjusted OR = 0.441, 95% CI 0.246–0.792, P = 0.006; BMI ≥25.7 kg/m², adjusted OR = 0.558, 95% CI 0.315–0.998, P₂ = 0.045). Presence of a benign uterine mass was an independent risk factor for multifocal PTC in patients aged ≥49 years (adjusted OR = 1.397, 95% CI 1.088–1.793, P = 0.009) or with a BMI <21.5 kg/m² (OR adjusted = 1.745, 95% CI 1.214–2.509, P = 0.003).

Conclusion

The presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter and a protective factor against extrathyroidal extension of PTC, while the presence of a benign uterine mass was an independent risk factor for multifocal PTC. Data from this study may help surgeons propose more personalized treatment plans when encountering patients with PTC and female-specific benign tumors.

THE ROLE OF E2/P RATIO IN THE ETIOLOGY OF FIBROCYSTIC BREAST DISEASE, MASTALGIA AND MASTODYNIA

- The aim of the study was to assess the role of the estradiol and progesterone relationship during the late luteal phase and the occurrence of fibrocystic breast disease (FBD). The concentration of estradiol/progesterone was measured in the group of women with FBD as study group (n=50) and control group of women without FBD (n=40). All women had regular ovulation cycles. Blood samples for estradiol (E2), progesterone (P) and prolactin determination were obtained in the morning at 8 am on days 21 and 24 of menstrual cycle. Significant mastalgia and mastodynia history in women with FBD was obtained with yes or no questionnaire. FBD diagnosis was confirmed with ultrasound (size and number of simple cysts). In the control group, a reduced E2/P ratio was noticed from day 21 to day 24 of the cycle (from 14.8±11.5 pg/mL to 9.1±6.1 pg/mL; p<0.05), which was not recorded in the group of women with FBD (study group). Even the slightest disturbance of the E2/P ratio may contribute to the occurrence of FBD with clinical manifestations of mastalgia and mastodynia.

Psychosocial stress is associated with benign breast disease in young Chinese women: results from Project ELEFANT

PURPOSE

Psychosocial stress, including bereavement and work-related stress, is associated with the risk of breast cancer. However, it is unknown whether it may also be linked with increased risk of benign breast disease (BBD).

METHODS

Our study leveraged 61,907 women aged 17-55 years old from the Project ELEFANT study. BBD was diagnosed by clinician. Self-reported data on psychosocial stress over a 10-year period was retrospectively collected from questionnaires and categorised by cause (work, social and economic) and severity (none, low and high). Odd ratios (ORs) for the development of BBD were estimated using logistic regression. The model was adjusted for age, BMI, TSH levels, smoking, alcohol consumption, family history, age of menarche, oral contraceptive usage, education and occupation.

RESULTS

Within our study, 8% (4,914) of participants were diagnosed with BBD. Work-related stress [OR 1.57, 95% confidence interval (CI) 1.46-1.69] and financial stress (OR 1.34, 95% CI 1.24-1.44) were significantly associated with BBD incidence, with a smaller but still significant association with social stress (OR 1.11, 95% CI 1.01-1.21). The associations remained significant after exclusion of participants with first- and second-degree family history of breast disease. The presence of multiple forms of stress did not synergistically increase risk. The neutrophil-lymphocyte ratio (NLR), a marker of systemic inflammation and prognostic marker for breast cancer, was not associated with BBD.

CONCLUSIONS

Psychosocial stress, particularly work-related and financial stress, is associated with increased risk of benign breast disease among young Chinese women.

Atypical epithelial hyperplasia of the breast: state of the art

INTRODUCTION

Atypical epithelial hyperplasia (AEH) of the breast is considered benign histological lesions with breast cancer risk. This review focuses on clinical signification and management of AEH that remains controversial.

AREAS COVERED

A review of published studies was performed using medline database. In this review, we fully describe the current evidence available. In particular, we describe 1) data from immunohistochemistry and molecular studies that suggest AEH is a precursor of breast cancer; 2) epidemiological studies demonstrate low rate of breast cancer in women with AEH; 3) surgical excision is necessary after diagnosis of AEH, such as lobular carcinoma in situ or atypical ductal hyperplasia, on core needle biopsy; 4) although current recommendations are evolving to fewer (if not no) excisions for flat epithelial with atypia and classic lobular neoplasia found on percutaneous biopsy (without radiologic indications for excision). Expert commentary: HEA management steel need prospective evidences, but recent retrospective data give some clue for less invasive management for some of HEA.

Menopausal hormone therapy and cancer: changing clinical observations of target site specificity

Menopausal hormone therapy with estrogen plus progestin or estrogen alone (for women with prior hysterectomy) is still used by millions of women for climacteric symptom management throughout the world. Until 2002, hormone therapy influence on cancer risk and other chronic diseases was determined through observational study reports. Since then, results from the Women's Health Initiative randomized, placebo-controlled hormone therapy trials have substantially changed concepts regarding estrogen plus progestin and estrogen alone influence on the most common cancers in postmenopausal women. In these trials, estrogen plus progestin significantly increased breast cancer incidence and deaths from breast cancer, significantly increased deaths from lung cancer, significantly decreased endometrial cancer, and did not have a clinically significant influence on colorectal cancer. In contrast, estrogen alone use in women with prior hysterectomy significantly reduced breast cancer incidence and deaths from breast cancer without significant influence on colorectal cancer or lung cancer. These complex results are discussed in the context of known potential mediating mechanisms of action involved in interaction with steroid hormone receptors.

Insulin, estrogen, inflammatory markers, and risk of benign proliferative breast disease

Women with benign proliferative breast disease (BPBD) are at increased risk for developing breast cancer. Evidence suggests that accumulation of adipose tissue can influence breast cancer development via hyperinsulinemia, increased estrogen, and/or inflammation. However, there are limited data investigating these pathways with respect to risk of BPBD. We evaluated serologic markers from these pathways in a case-control study of postmenopausal women nested within the Women's Health Initiative Clinical Trial. Cases were the 667 women who developed BPBD during follow-up, and they were matched to 1,321 controls. Levels of insulin, estradiol, C-reactive protein (CRP), and adiponectin were measured in fasting serum collected at baseline. Conditional logistic regression models were used to estimate ORs for the association of each factor with BPBD risk. Among nonusers of hormone therapy, fasting serum insulin was associated with a statistically significant increase in risk of BPBD (OR for highest vs. lowest quartile = 1.80; 95% confidence interval, CI, 1.16-2.79; Ptrend = 0.003) as were levels of estradiol (OR for highest vs. lowest tertile = 1.89; 95% CI, 1.26-2.83; Ptrend = 0.02) and CRP (OR for highest vs. lowest quartile = 2.46; 95% CI, 1.59-3.80; Ptrend < 0.001). Baseline adiponectin level was inversely associated with BPBD risk (OR for highest vs. lowest quartile = 0.47; 95% CI, 0.31-0.71; Ptrend < 0.001). These associations persisted after mutual adjustment, but were not observed among users of either estrogen alone or of estrogen plus progestin hormone therapy. Our results indicate that serum levels of estrogen, insulin, CRP, and adiponectin are independent risk factors for BPBD and suggest that the estrogen, insulin, and inflammation pathways are associated with the early stages of breast cancer development.

Benign proliferative breast diseases among female patients at a sub-Saharan Africa tertiary hospital: a cross sectional study

Background

Non-cancerous diseases of the breast have assumed increasing importance because of the public awareness of breast cancer. These benign diseases are a recognized important risk factor for later breast cancer which can develop in either breast. The risk estimate of these benign breast diseases has not been well established in sub Saharan Africa. Women with benign proliferative or atypical breast lesions have a two- fold risk of developing breast cancer in western populations. The purpose of this study therefore was to determine the prevalence of proliferative disease ( BPBD) with and without atypia among Ugandan Black women.

Methods

A cross-sectional descriptive study conducted at Mulago Hospital Breast Clinic between January 2012 and June 2012; 208 women aged 12 years and above with palpable breast lumps were screened. Fine needle aspiration biopsies were taken for cytological examination.

Results

Of the 208 women with benign breast lumps screened, 195 were recruited in the study. The prevalence of BPBD was 18% (35/195). BPBD with atypia was 5.6% (11/195). The mean age and body mass index (BMI) were 28.4 years and 23.26 kg/m² respectively. The commonest lesions were fibroadenomas for 57%, (111/195), and fibrocystic change were 21% (40/195). Most BPBD with atypia lesions were in the fibrocystic category.

Conclusions

Benign proliferative breast diseases are common, found mostly among premenopausal women. A significant proportion of BPBD had atypical proliferation. An accurate breast cancer risk estimate study for BPBD is recommended.

2D-DIGE proteomic analysis of changes in estrogen/progesterone-induced rat breast hyperplasia upon treatment with the Mongolian remedy RuXian-I

RuXian-I has traditionally been used as a remedy for breast hyperplasia in the Inner Mongolia Autonomous Region of China. As a first step toward the investigation of biomarkers associated with RuXian-I treatment, a proteome-wide analysis of rat breast tissue was conducted. First, rat breast hyperplasia was induced by injection of estradiol and progesterone. After treatment with RuXian-I, there is a marked decrease in the hyperplasia, as can be shown by decreases in the nipple diameter and the pathological changes in breast. Subsequently, we used an approach that integrates size-based 2D-DIGE, MALDI-TOF/TOF-MS, and bioinformatics to analyze data from the control group, the model group and the RuXian-I treatment group. Using this approach, seventeen affected proteins were identified. Among these, 15 (including annexin A1, annexin A2, superoxide dismutase [Mn], peroxiredoxin-1, translationally-controlled tumor protein and α B-crystallin) were significantly up-regulated in the model group and down-regulated upon treatment with RuXian-I, and two (Tpil protein and myosin-4) have the opposite change trend. The expression of annexin A1 was confirmed using immunohistochemistry. The expression of superoxide dismutase (SOD) activity was confirmed biochemically. These results indicated that RuXian-I treats rat breast hyperplasia through regulation of cell cycle, immune system, metabolic, signal transduction, etc. The differential expressions of these proteins (annexin A1, superoxide dismutase [Mn], alpha B-crystallins and translationally controlled tumor protein, among others) were associated with occurrence and metastasis of breast cancer. These findings might provide not only far-reaching valuable insights into the mechanism of RuXian-I action, but also leads for prognosis and diagnosis of breast hyperplasia and breast cancer.

CDB-4124, a progesterone receptor modulator, inhibits mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis

CDB-4124 (Proellex or telapristone acetate) is a modulator of progesterone receptor (PR) signaling, which is currently employed in preclinical studies for prevention and treatment of breast cancer and has been used in clinical studies for treatment of uterine fibroids and endometriosis. Here we provide evidence for its action on steroid hormone-signaling, cell cycle-regulated genes and in vivo on mammary carcinogenesis. When CDB-4124 is given to rats at 200 mg/kg for 24 months, it prevents the development of spontaneous mammary hyperplastic and premalignant lesions. Also, CDB-4124 given as subcutaneous pellets at two different doses suppressed, dose dependently, N-methyl-N-nitrosourea (MNU)-induced mammary carcinogenesis. The high dose (30 mg, over 84 days) increased tumor latency from 66 ± 24 days to 87 ± 20 days (P < 0.02), decreased incidence from 85% to 35% (P < 0.001), and reduced multiplicity from 3.0 to 1.1 tumors/animal (P < 0.001). Tumor burden decreased from 2.6 g/animal to 0.26 g/animal (P < 0.01). CDB-4124 inhibited cell proliferation and induced apoptosis in MNU-induced mammary tumors, which correlated with a decreased proportion of PR(+) tumor cells and with decreased serum progesterone. CDB-4124 did not affect serum estradiol. In a mechanistic study employing T47D cells we found that CDB-4124 suppressed G(1)/G(0)-S transition by inhibiting CDK2 and CDK4 expressions, which correlated with inhibition of estrogen receptor (ER) expression. Taken together, these data indicate that CDB-4124 can suppress the development of precancerous lesions and carcinogen-induced ER(+) mammary tumors in rats, and may have implications for prevention and treatment of human breast cancer.

Rates of atypical ductal hyperplasia have declined with less use of postmenopausal hormone treatment: findings from the Breast Cancer Surveillance Consortium

AIM

To examine risk factors and rates of atypical ductal hyperplasia (ADH) with and without associated breast cancer over time and tumor characteristics of breast cancer with and without associated ADH in women previously screened with mammography.

METHODS

Data on screening mammograms done between 1996 and 2005 were collected from mammography registries that participate in the Breast Cancer Surveillance Consortium. Associations between age, family history of breast cancer, postmenopausal hormone treatment (HT), and final pathology result (ADH or cancer with or without ADH in the same breast) were examined. Rates of different outcomes were calculated per exam year. Tumor characteristics of cancers with and without associated ADH were compared.

RESULTS

A total of 2,453,483 screening mammograms were associated with 1,064 biopsies with ADH, 833 breast cancers with ADH, and 8,161 cancers with no ADH. Postmenopausal HT use decreased significantly from 35% to 11% during the study period. Rates of ADH decreased from a peak of 5.5/10,000 mammograms in 1999 to 2.4/10,000 in 2005. Rates of cancer with ADH decreased from a peak of 4.3/10,000 mammograms in 2003 to 3.3/10,000 in 2005. ADH and breast cancer were significantly associated with use of postmenopausal HT. Cancer associated with ADH was of lower grade and stage and more estrogen receptor positive than cancer with no ADH.

SUMMARY

Postmenopausal HT is associated with an increased risk of ADH with or without cancer. Rates of ADH have decreased over the past decade, which may be partially explained by the significant reduction in use of postmenopausal HT.

Short-term prophylactic tamoxifen reduces the incidence of antiestrogen-resistant/estrogen receptor-positive/progesterone receptor-negative mammary tumors

Although many estrogen receptor-positive (ER+) breast cancers are effectively treated with selective estrogen receptor modulators and down-regulators (SERM/SERD), some are highly resistant. Resistance is more likely if primary cancers are devoid of progesterone receptors (PR-) or have high levels of growth factor activity. In this study, a transgenic mouse line that expresses transforming growth factor-alpha (NRL-TGFalpha mice) and that develops ER+/PR- mammary tumors was used to assess the possible effects of (a) therapeutic delivery of the SERM, tamoxifen, or SERD, ICI I82,780 (ICI), on the growth of established tumors and (b) short-term prophylactic tamoxifen administration on the initial development of new mammary tumors. To determine the therapeutic effects of tamoxifen and ICI on the growth of established tumors, mice were exposed to 3 weeks of drug treatment. Neither drug influenced tumor growth or glandular pathology. To determine if early prophylactic tamoxifen could alter tumorigenesis, a 60-day tamoxifen treatment was initiated in 8-week-old mice. Compared with placebo-treated mice, tamoxifen reduced tumor incidence by 50% and significantly decreased the degree of mammary hyperplasia. Prophylactic tamoxifen also significantly extended the life span of tumor-free mice. These data show that in this mouse model, established ER+/PR- mammary tumors are resistant to SERM/SERD treatment but the development of new mammary tumors can be prevented by an early course of tamoxifen. This study validates the utility of NRL-TGFalpha mice for (a) identifying candidate biomarkers of efficacious tamoxifen chemoprevention and (b) modeling the evolution of tamoxifen resistance.