Prognostic Characteristics of Breast Cancer Among Postmenopausal Hormone Users in a Screened Population

Population Attributable Risk of Advanced-Stage Breast Cancer by Race and Ethnicity

Importance

Advanced-stage breast cancer rates vary by race and ethnicity, with Black women having a 2-fold higher rate than White women among regular screeners. Clinical risk factors that explain a large proportion of advanced breast cancers by race and ethnicity are unknown.

Objective

To evaluate the population attributable risk proportions (PARPs) for advanced-stage breast cancer (prognostic pathologic stage IIA or higher) associated with clinical risk factors among routinely screened premenopausal and postmenopausal women by race and ethnicity.

Design, Setting, and Participants

This cohort study used data collected prospectively from Breast Cancer Surveillance Consortium community-based breast imaging facilities from January 2005 to June 2018. Participants were women aged 40 to 74 years undergoing 3 331 740 annual (prior screening within 11-18 months) or biennial (prior screening within 19-30 months) screening mammograms associated with 1815 advanced breast cancers diagnosed within 2 years of screening examinations. Data analysis was performed from September 2022 to August 2023.

Exposures

Heterogeneously or extremely dense breasts, first-degree family history of breast cancer, overweight/obesity (body mass index >25.0), history of benign breast biopsy, and screening interval (biennial vs annual) stratified by menopausal status and race and ethnicity (Asian or Pacific Islander, Black, Hispanic/Latinx, White, other/multiracial).

Main Outcomes and Measures

PARPs for advanced breast cancer.

Results

Among 904 615 women, median (IQR) age was 57 (50-64) years. Of the 3 331 740 annual or biennial screening mammograms, 10.8% were for Asian or Pacific Islander women; 9.5% were for Black women; 5.3% were for Hispanic/Latinx women; 72.0% were for White women; and 2.0% were for women of other races and ethnicities, including those who were Alaska Native, American Indian, 2 or more reported races, or other. Body mass index PARPs were larger for postmenopausal vs premenopausal women (30% vs 22%) and highest for postmenopausal Black (38.6%; 95% CI, 32.0%-44.8%) and Hispanic/Latinx women (31.8%; 95% CI, 25.3%-38.0%) and premenopausal Black women (30.3%; 95% CI, 17.7%-42.0%), with overall prevalence of having overweight/obesity highest in premenopausal Black (84.4%) and postmenopausal Black (85.1%) and Hispanic/Latinx women (72.4%). Breast density PARPs were larger for premenopausal vs postmenopausal women (37% vs 24%, respectively) and highest among premenopausal Asian or Pacific Islander (46.6%; 95% CI, 37.9%-54.4%) and White women (39.8%; 95% CI, 31.7%-47.3%) whose prevalence of dense breasts was high (62%-79%). For premenopausal and postmenopausal women, PARPs were small for family history of breast cancer (5%-8%), history of breast biopsy (7%-12%), and screening interval (2.1%-2.3%).

Conclusions and Relevance

In this cohort study among routinely screened women, the proportion of advanced breast cancers attributed to biennial vs annual screening was small. To reduce the number of advanced breast cancer diagnoses, primary prevention should focus on interventions that shift patients with overweight and obesity to normal weight.

Menopausal hormone therapy and change in physical activity in the Women's Health Initiative hormone therapy clinical trials

OBJECTIVE

The menopausal transition results in a progressive decrease in circulating estrogen levels. Experimental evidence in rodents has indicated that estrogen depletion leads to a reduction of energy expenditure and physical activity. It is unclear whether treatment with estrogen therapy increases physical activity level in postmenopausal women.

METHODS

A total of 27,327 postmenopausal women aged 50-79 years enrolled in the Women's Health Initiative randomized double-blind trials of menopausal hormone therapy. Self-reported leisure-time physical activity at baseline, and years 1, 3, and 6 was quantified as metabolic equivalents (MET)-h/wk. In each trial, comparison between intervention and placebo groups of changes in physical activity levels from baseline to follow-up assessment was examined using linear regression models.

RESULTS

In the CEE-alone trial, the increase in MET-h/wk was greater in the placebo group compared with the intervention group at years 3 ( P = 0.002) and 6 ( P < 0.001). Similar results were observed when analyses were restricted to women who maintained an adherence rate ≥80% during the trial or who were physically active at baseline. In the CEE + MPA trial, the primary analyses did not show significant differences between groups, but the increase of MET-h/wk was greater in the placebo group compared with the intervention group at year 3 ( P = 0.004) among women with an adherence rate ≥80%.

CONCLUSIONS

The results from this clinical trial do not support the hypothesis that estrogen treatment increases physical activity among postmenopausal women.

Cumulative Advanced Breast Cancer Risk Prediction Model Developed in a Screening Mammography Population

BACKGROUND

Estimating advanced breast cancer risk in women undergoing annual or biennial mammography could identify women who may benefit from less or more intensive screening. We developed an actionable model to predict cumulative 6-year advanced cancer (prognostic pathologic stage II or higher) risk according to screening interval.

METHODS

We included 931 186 women aged 40-74 years in the Breast Cancer Surveillance Consortium undergoing 2 542 382 annual (prior mammogram within 11-18 months) or 752 049 biennial (prior within 19-30 months) screening mammograms. The prediction model includes age, race and ethnicity, body mass index, breast density, family history of breast cancer, and prior breast biopsy subdivided by menopausal status and screening interval. We used fivefold cross-validation to internally validate model performance. We defined higher than 95th percentile as high risk (>0.658%), higher than 75th percentile to 95th or less percentile as intermediate risk (0.380%-0.658%), and 75th or less percentile as low to average risk (<0.380%).

RESULTS

Obesity, high breast density, and proliferative disease with atypia were strongly associated with advanced cancer. The model is well calibrated and has an area under the receiver operating characteristics curve of 0.682 (95% confidence interval = 0.670 to 0.694). Based on women's predicted advanced cancer risk under annual and biennial screening, 69.1% had low or average risk regardless of screening interval, 12.4% intermediate risk with biennial screening and average risk with annual screening, and 17.4% intermediate or high risk regardless of screening interval.

CONCLUSION

Most women have low or average advanced cancer risk and can undergo biennial screening. Intermediate-risk women may consider annual screening, and high-risk women may consider supplemental imaging in addition to annual screening.

Hormone therapy in the postmenopausal years: considering benefits and risks in clinical practice

BACKGROUND

Menopausal symptoms can be very distressing and considerably affect a woman's personal and social life. It is becoming more and more evident that leaving bothersome symptoms untreated in midlife may lead to altered quality of life, reduced work productivity and, possibly, overall impaired health. Hormone therapy (HT) for the relief of menopausal symptoms has been the object of much controversy over the past two decades. At the beginning of the century, a shadow was cast on the use of HT owing to the concern for cardiovascular and cerebrovascular risks, and breast cancer, arising following publication of a large randomized placebo-controlled trial. Findings of a subanalysis of the trial data and extended follow-up studies, along with other more modern clinical trials and observational studies, have provided new evidence on the effects of HT.

OBJECTIVE AND RATIONALE

The goal of the following paper is to appraise the most significant clinical literature on the effects of hormones in postmenopausal women, and to report the benefits and risks of HT for the relief of menopausal symptoms.

SEARCH METHODS

A Pubmed search of clinical trials was performed using the following terms: estrogens, progestogens, bazedoxifene, tibolone, selective estrogen receptor modulators, tissue-selective estrogen complex, androgens, and menopause.

OUTCOMES

HT is an effective treatment for bothersome menopausal vasomotor symptoms, genitourinary syndrome, and prevention of osteoporotic fractures. Women should be made aware that there is a small increased risk of stroke that tends to persist over the years as well as breast cancer risk with long-term estrogen-progestin use. However, healthy women who begin HT soon after menopause will probably earn more benefit than harm from the treatment. HT can improve bothersome symptoms, all the while conferring offset benefits such as cardiovascular risk reduction, an increase in bone mineral density and a reduction in bone fracture risk. Moreover, a decrease in colorectal cancer risk is obtainable in women treated with estrogen-progestin therapy, and an overall but nonsignificant reduction in mortality has been observed in women treated with conjugated equine estrogens alone or combined with estrogen-progestin therapy. Where possible, transdermal routes of HT administration should be preferred as they have the least impact on coagulation. With combined treatment, natural progesterone should be favored as it is devoid of the antiapoptotic properties of other progestogens on breast cells. When beginning HT, low doses should be used and increased gradually until effective control of symptoms is achieved. Unless contraindications develop, patients may choose to continue HT as long as the benefits outweigh the risks. Regular reassessment of the woman's health status is mandatory. Women with premature menopause who begin HT before 50 years of age seem to have the most significant advantage in terms of longevity.

WIDER IMPLICATIONS

In women with bothersome menopausal symptoms, HT should be considered one of the mainstays of treatment. Clinical practitioners should tailor HT based on patient history, physical characteristics, and current health status so that benefits outweigh the risks.

KDM3B-ETF1 fusion gene downregulates LMO2 via the WNT/β-catenin signaling pathway, promoting metastasis of invasive ductal carcinoma

Breast cancer is the most common malignancy for women, with invasive ductal carcinoma being the largest subtype of breast cancers, accounting for 75-80% of cases. However, the underlying mechanism of invasive ductal carcinoma remains unclear. In this study, we investigate the possible effects KDM3B-ETF1 fusion gene has on breast cancer cell metastasis, invasion and its downstream signaling mediators as revealed from RNA sequence data analysis. As predicted, KDM3B-ETF1 expression was increased in breast cancer tissues and cells. Overexpression of KDM3B-ETF1 in cancer cell lines promoted the growth and invasion of breast cancer cells, while KDM3B-ETF1 knockdown showed the opposite effects on malignant cell growth and invasion both in vivo and in vitro as evidenced by cell counting kit-8, Transwell assay and tumor xenograft in nude mice. On the contrary, LIM Domain Only 2 (LMO2) expression was significantly reduced in breast cancer tissues and cells. According to chromatin immunoprecipitation and Western blot analysis, KDM3B-ETF1 targets LMO2 and reduced the expression of LMO2, leading to an increase in WNT/β-catenin signaling pathway and thus promoting invasion. In conclusion, fusion gene KDM3B-ETF1 inhibits LMO2, activates the Wnt/β-catenin signaling pathway that leads to increased breast cancer cell invasion and metastasis, providing a novel insight into developing therapeutic strategies. These results provide novel insights into the molecular mechanism of invasive ductal carcinomas, which may lead to potential therapeutic targets.

Use of postmenopausal hormone therapies and risk of histology- and hormone receptor-defined breast cancer: results from a 15-year prospective analysis of NIH-AARP cohort

Background

Menopausal hormone therapy (MHT) increases breast cancer (BC) risk, but cohort studies largely consider use only at enrollment. Evidence is limited on how changes in MHT use alter the magnitude of risk, and whether risk varies between invasive and in situ cancer, by histology or by hormone receptor status.

Methods

We investigated the roles of estrogen-alone therapy (ET) and estrogen plus progestin therapy (EPT) on BC risk overall, by histology and estrogen receptor (ER) and progesterone receptor (PR) status, and on incidence of in situ disease, in the NIH-AARP cohort. Participants included 118,760 postmenopausal women (50–71 years), of whom 63.5% (n = 75,398) provided MHT use information at baseline in 1996 and in a follow-up survey in 2004, subsequent to the dissemination in 2002 of the Women’s Health Initiative trial safety concerns regarding EPT. ET analyses included 50,476 women with hysterectomy (31,439 with follow-up data); EPT analyses included 68,284 women with intact uteri (43,959 with follow-up data). Adjusted hazard ratios (HRs) were estimated using Cox proportional hazards models using age as the time metric with follow-up through 2011.

Results

Eight thousand three hundred thirty-three incident BC cases were accrued, 2479 in women with follow-up data. BC risk was not elevated in current ET users at baseline (HR = 1.05, 95% confidence interval [CI] CI = 0.95–1.16) but was higher in women continuing use through 2004 (HR = 1.35, 95% CI = 1.04–1.75). Ever EPT use at baseline was associated with elevated BC risk overall (HR = 1.54 (1.44–1.64), with a doubling in risk for women with 10 or more years of use, for in situ disease, and across subtypes defined by histology and ER/PR status (all p < 0.004). Risk persisted in women who continued EPT through 2004 (HR = 1.80, 95% CI = 1.39–2.32). In contrast, no association was seen in women who discontinued EPT before 2004 (HR = 1.14, 95% CI = 0.99–1.30).

Conclusions

ET use was not associated with BC risk in this cohort, although excess risk was suggested in women who continued use through 2004. EPT use was linked to elevated in situ and invasive BC risk, and elevated risk across invasive BC histologic and hormone receptor-defined subtypes, with the highest risk for women who continued use through the 2004 follow-up survey.

Supplementary information

The online version contains supplementary material available at 10.1186/s13058-020-01365-9.

Underlying Breast Cancer Risk and Menopausal Hormone Therapy

The recent Collaborative Group on Hormonal Factors in Breast Cancer (CGHFBC) publication calculated the attributable risk of breast cancer from use of estrogen alone and estrogen plus a synthetic progestogen for less than 5 to 15 or more years of use. This CGHFB report calculated attributable risk based on their findings of relative risk from pooled data from 58 studies. Notably, neither the CGHFBC nor other previous studies have examined the effect of underlying risk of breast cancer on attributable risk. This omission prompted us to determine the magnitude of the effect of underlying risk on attributable risk in this perspective. Meaningful communication of the potential risk of menopausal hormonal therapy requires providing women with the estimated risk above their existing underlying risk (ie, attributable risk). Therefore, we have estimated attributable risks from the data published by the CGHFBC, taking into account varying degrees of underlying risk. Based on the Endocrine Society Guideline on Menopausal Hormone Therapy (MHT), we divided groups into 3 categories of risk: low (1.5%), intermediate (3.0%), and high (6.0%) underlying risk of breast cancer over 5 years. In women taking estrogen plus a synthetic progestogen for 5 to 9 years, the attributable risks of MHT increased from 12, to 42, to 85 additional women per 1000 in the low-, intermediate-, and high-risk groups, respectively. The attributable risks for estrogen alone were lower but also increased based on underlying risk. Notably, the attributable risks were amplified with duration of MHT use, which increased both relative risk and breast cancer incidence.

The impact of ductal carcinoma in situ on health services utilization

PURPOSE

To determine the intermediate-term impact of diagnosis and treatment of ductal carcinoma in situ of the breast (DCIS) on health services utilization, we compared utilization by cases of DCIS to unaffected controls.

METHODS

We identified a population-based cohort of Ontario females diagnosed with DCIS between 2010 and 2015. We matched 5 controls without any history of cancer to each case, on the date of diagnosis of the case (the index date), by age, annual mammography history, socioeconomic status, and comorbidity. We identified billing claims and hospital records, during the interval 13 to 60 months prior to, and subsequent to the index date, and computed rates per 100 person-years during both intervals, to conduct a difference-in-differences analysis. We used negative binomial regression to test if the change in rates in health services differed between cases and controls.

RESULTS

Visits with a breast diagnosis code, and claims for breast surgery and imaging, were significantly increased among cases compared to controls (all p values < 0.0001) after DCIS;however, there was no increase in visits for anxiety or depression (RR 1.13 (95% CI 0.97, 1.32, p = 0.11), visits to psychiatrists (RR 1.07 (95% CI 0.82, 1.40) p = 0.6), or hospital procedures other than breast surgery (RR 1.10 (95% CI 0.88, 1.37) p = 0.4).

CONCLUSIONS

DCIS is associated with more visits and procedures related to the breast compared to controls following diagnosis and treatment, but other health services utilization and visits related to anxiety and depression were not increased.

The 2017 hormone therapy position statement of The North American Menopause Society

The 2017 Hormone Therapy Position Statement of The North American Menopause Society (NAMS) updates the 2012 Hormone Therapy Position Statement of The North American Menopause Society and identifies future research needs. An Advisory Panel of clinicians and researchers expert in the field of women's health and menopause was recruited by NAMS to review the 2012 Position Statement, evaluate new literature, assess the evidence, and reach consensus on recommendations, using the level of evidence to identify the strength of recommendations and the quality of the evidence. The Panel's recommendations were reviewed and approved by the NAMS Board of Trustees.Hormone therapy (HT) remains the most effective treatment for vasomotor symptoms (VMS) and the genitourinary syndrome of menopause (GSM) and has been shown to prevent bone loss and fracture. The risks of HT differ depending on type, dose, duration of use, route of administration, timing of initiation, and whether a progestogen is used. Treatment should be individualized to identify the most appropriate HT type, dose, formulation, route of administration, and duration of use, using the best available evidence to maximize benefits and minimize risks, with periodic reevaluation of the benefits and risks of continuing or discontinuing HT.For women aged younger than 60 years or who are within 10 years of menopause onset and have no contraindications, the benefit-risk ratio is most favorable for treatment of bothersome VMS and for those at elevated risk for bone loss or fracture. For women who initiate HT more than 10 or 20 years from menopause onset or are aged 60 years or older, the benefit-risk ratio appears less favorable because of the greater absolute risks of coronary heart disease, stroke, venous thromboembolism, and dementia. Longer durations of therapy should be for documented indications such as persistent VMS or bone loss, with shared decision making and periodic reevaluation. For bothersome GSM symptoms not relieved with over-the-counter therapies and without indications for use of systemic HT, low-dose vaginal estrogen therapy or other therapies are recommended.This NAMS position statement has been endorsed by Academy of Women's Health, American Association of Clinical Endocrinologists, American Association of Nurse Practitioners, American Medical Women's Association, American Society for Reproductive Medicine, Asociación Mexicana para el Estudio del Climaterio, Association of Reproductive Health Professionals, Australasian Menopause Society, Chinese Menopause Society, Colegio Mexicano de Especialistas en Ginecologia y Obstetricia, Czech Menopause and Andropause Society, Dominican Menopause Society, European Menopause and Andropause Society, German Menopause Society, Groupe d'études de la ménopause et du vieillissement Hormonal, HealthyWomen, Indian Menopause Society, International Menopause Society, International Osteoporosis Foundation, International Society for the Study of Women's Sexual Health, Israeli Menopause Society, Japan Society of Menopause and Women's Health, Korean Society of Menopause, Menopause Research Society of Singapore, National Association of Nurse Practitioners in Women's Health, SOBRAC and FEBRASGO, SIGMA Canadian Menopause Society, Società Italiana della Menopausa, Society of Obstetricians and Gynaecologists of Canada, South African Menopause Society, Taiwanese Menopause Society, and the Thai Menopause Society. The American College of Obstetricians and Gynecologists supports the value of this clinical document as an educational tool, June 2017. The British Menopause Society supports this Position Statement.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY POSITION STATEMENT ON MENOPAUSE-2017 UPDATE

EXECUTIVE SUMMARY This American Association of Clinical Endocrinologists (AACE)/American College of Endocrinology (ACE) Position Statement is designed to update the previous menopause clinical practice guidelines published in 2011 but does not replace them. The current document reviews new clinical trials published since then as well as new information regarding possible risks and benefits of therapies available for the treatment of menopausal symptoms. AACE reinforces the recommendations made in its previous guidelines and provides additional recommendations on the basis of new data. A summary regarding this position statement is listed below: New information available from randomized clinical trials and epidemiologic studies reported after 2011 was critically reviewed. No previous recommendations from the 2011 menopause clinical practice guidelines have been reversed or changed. Newer information enhances AACE's guidance for the use of hormone therapy in different subsets of women. Newer information helps to support the use of various types of estrogens, selective estrogen-receptor modulators (SERMs), and progesterone, as well as the route of delivery. Newer information supports the previous recommendation against the use of bioidentical hormones. The use of nonhormonal therapies for the symptomatic relief of menopausal symptoms is supported. Newer information enhances AACE's guidance for the use of hormone therapy in different subsets of women. Newer information helps to support the use of various types of estrogens, SERMs, and progesterone, as well as the route of delivery. Newer information supports the previous recommendation against the use of bioidentical hormones. The use of nonhormonal therapies for the symptomatic relief of menopausal symptoms is supported. New recommendations in this position statement include: 1.

RECOMMENDATION

the use of menopausal hormone therapy in symptomatic postmenopausal women should be based on consideration of all risk factors for cardiovascular disease, age, and time from menopause. 2.

RECOMMENDATION

the use of transdermal as compared with oral estrogen preparations may be considered less likely to produce thrombotic risk and perhaps the risk of stroke and coronary artery disease. 3.

RECOMMENDATION

when the use of progesterone is necessary, micronized progesterone is considered the safer alternative. 4.

RECOMMENDATION

in symptomatic menopausal women who are at significant risk from the use of hormone replacement therapy, the use of selective serotonin re-uptake inhibitors and possibly other nonhormonal agents may offer significant symptom relief. 5.

RECOMMENDATION

AACE does not recommend use of bioidentical hormone therapy. 6.

RECOMMENDATION

AACE fully supports the recommendations of the Comité de l'Évolution des Pratiques en Oncologie regarding the management of menopause in women with breast cancer. 7.

RECOMMENDATION

HRT is not recommended for the prevention of diabetes. 8.

RECOMMENDATION

In women with previously diagnosed diabetes, the use of HRT should be individualized, taking in to account age, metabolic, and cardiovascular risk factors.

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; BMI = body mass index; CAC = coronary artery calcification; CEE = conjugated equine estrogen; CEPO = Comité de l'Évolution des Pratiques en Oncologie; CAD = coronary artery disease; CIMT = carotid intima media thickness; CVD = cardiovascular disease; FDA = Food and Drug Administration; HDL = high-density lipoprotein; HRT = hormone replacement therapy; HT = hypertension; KEEPS = Kronos Early Estrogen Prevention Study; LDL = low-density lipoprotein; MBS = metabolic syndrome; MPA = medroxyprogesterone acetate; RR = relative risk; SERM = selective estrogen-receptor modulator; SSRI = selective serotonin re-uptake inhibitor; VTE = venous thrombo-embolism; WHI = Women's Health Initiative.

Risk Factors That Increase Risk of Estrogen Receptor-Positive and -Negative Breast Cancer

Background

Risk factors may differentially influence development of estrogen receptor (ER)-positive vs -negative breast cancer. We examined associations with strong, prevalent risk factors by ER subtype.

Methods

Of 1 279 443 women age 35 to 74 years participating in the Breast Cancer Surveillance Consortium, 14 969 developed ER-positive and 3617 developed ER-negative invasive breast cancer. We calculated hazard ratios (HRs) using Cox regression and compared ER subtype hazard ratios at representative ages or by menopausal status using Wald tests. All statistical tests were two-sided.

Results

For women age 40 years, compared with no prior biopsy, ER-positive vs ER-negative HRs were 1.53 (95% CI = 1.30 to 1.81) vs 1.26 (95% CI = 0.90 to 1.76) for nonproliferative disease, 1.63 (95% CI = 1.23 to 2.17) vs 1.41 (95% CI = 0.78 to 2.57) for proliferative disease without atypia, and 4.47 (95% CI = 2.88 to 6.96) vs 0.20 (95% CI = 0.02 to 2.51) for proliferative disease with atypia. Benign disease proliferation risk was stronger for ER-positive than ER-negative cancer for women age 35 years (Wald P = .04), age 40 years (Wald P = .04), and age 50 years (Wald P = .06). Among pre/perimenopausal women, body mass index (BMI) had a stronger association with ER-negative than ER-positive cancer (obese II/III vs. normal weight: HR = 1.52, 95% CI = 1.19 to 1.94; vs 1.21, 95% CI = 1.08 to 1.36). Increasing BMI similarly increased ER-positive and ER-negative cancer risk among postmenopausal hormone users (Wald P = .15) and nonusers (Wald P = .08). Associations with ER subtype varied by race/ethnicity across all ages (P < .001) and by family history of breast cancer and breast density for specific ages.

Conclusions

Strength of risk factor associations differed by ER subtype. Separate risk models for ER subtypes may improve identification of women for targeted prevention strategies.

Breast Tumor Prognostic Characteristics and Biennial vs Annual Mammography, Age, and Menopausal Status

IMPORTANCE

Screening mammography intervals remain under debate in the United States.

OBJECTIVE

To compare the proportion of breast cancers with less vs more favorable prognostic characteristics in women screening annually vs biennially by age, menopausal status, and postmenopausal hormone therapy (HT) use.

DESIGN, SETTING, AND PARTICIPANTS

This was a study of a prospective cohort from 1996 to 2012 at Breast Cancer Surveillance Consortium facilities. A total of 15,440 women ages 40 to 85 years with breast cancer diagnosed within 1 year of an annual or within 2 years of a biennial screening mammogram.

EXPOSURES

We updated previous analyses by using narrower intervals for defining annual (11-14 months) and biennial (23-26 months) screening.

MAIN OUTCOMES AND MEASURES

We defined less favorable prognostic characteristics as tumors that were stage IIB or higher, size greater than 15 mm, positive nodes, and any 1 or more of these characteristics. We used log-binomial regression to model the proportion of breast cancers with less favorable characteristics following a biennial vs annual screen by 10-year age groups and by menopausal status and current postmenopausal HT use.

RESULTS

Among 15,440 women with breast cancer, most were 50 years or older (13,182 [85.4%]), white (12,063 [78.1%]), and postmenopausal (9823 [63.6%]). Among 2027 premenopausal women (13.1%), biennial screeners had higher proportions of tumors that were stage IIB or higher (relative risk [RR], 1.28 [95% CI, 1.01-1.63]; P=.04), size greater than 15 mm (RR, 1.21 [95% CI, 1.07-1.37]; P=.002), and with any less favorable prognostic characteristic (RR, 1.11 [95% CI, 1.00-1.22]; P=.047) compared with annual screeners. Among women currently taking postmenopausal HT, biennial screeners tended to have tumors with less favorable prognostic characteristics compared with annual screeners; however, 95% CIs were wide, and differences were not statistically significant (for stage 2B+, RR, 1.14 [95% CI, 0.89-1.47], P=.29; size>15 mm, RR, 1.13 [95% CI, 0.98-1.31], P=.09; node positive, RR, 1.18 [95% CI, 0.98-1.42], P=.09; any less favorable characteristic, RR, 1.12 [95% CI, 1.00-1.25], P=.053). The proportions of tumors with less favorable prognostic characteristics were not significantly larger for biennial vs annual screeners among postmenopausal women not taking HT (eg, any characteristic: RR, 1.03 [95% CI, 0.95-1.12]; P=.45), postmenopausal HT users after subdividing by type of hormone use (eg, any characteristic: estrogen+progestogen users, RR, 1.16 [95% CI, 0.91-1.47]; P=.22; estrogen-only users, RR, 1.14 [95% CI, 0.94-1.37]; P=.18), or any 10-year age group (eg, any characteristic: ages 40-49 years, RR, .1.04 [95% CI, 0.94-1.14]; P=.48; ages 50-59 years, RR, 1.03 [95% CI, 0.94-1.12]; P=.58; ages 60-69 years, RR, 1.07 [95% CI, 0.97-1.19]; P=.18; ages 70-85 years, RR, 1.05 [95% CI, 0.94-1.18]; P=.35).

CONCLUSIONS AND RELEVANCE

Premenopausal women diagnosed as having breast cancer following biennial vs annual screening mammography are more likely to have tumors with less favorable prognostic characteristics. Postmenopausal women not using HT who are diagnosed as having breast cancer following a biennial or annual screen have similar proportions of tumors with less favorable prognostic characteristics.

Factors Associated With Rates of False-Positive and False-Negative Results From Digital Mammography Screening: An Analysis of Registry Data

BACKGROUND

Women screened with digital mammography may receive false-positive and false-negative results and subsequent imaging and biopsies. How these outcomes vary by age, time since the last screening, and individual risk factors is unclear.

OBJECTIVE

To determine factors associated with false-positive and false-negative digital mammography results, additional imaging, and biopsies among a general population of women screened for breast cancer.

DESIGN

Analysis of registry data.

SETTING

Participating facilities at 5 U.S. Breast Cancer Surveillance Consortium breast imaging registries with linkages to pathology databases and tumor registries.

PATIENTS

405,191 women aged 40 to 89 years screened with digital mammography between 2003 and 2011. A total of 2963 were diagnosed with invasive cancer or ductal carcinoma in situ within 12 months of screening.

MEASUREMENTS

Rates of false-positive and false-negative results and recommendations for additional imaging and biopsies from a single screening round; comparisons by age, time since the last screening, and risk factors.

RESULTS

Rates of false-positive results (121.2 per 1000 women [95% CI, 105.6 to 138.7]) and recommendations for additional imaging (124.9 per 1000 women [CI, 109.3 to 142.3]) were highest among women aged 40 to 49 years and decreased with increasing age. Rates of false-negative results (1.0 to 1.5 per 1000 women) and recommendations for biopsy (15.6 to 17.5 per 1000 women) did not differ greatly by age. Results did not differ by time since the last screening. False-positive rates were higher for women with risk factors, particularly family history of breast cancer; previous benign breast biopsy result; high breast density; and, for younger women, low body mass index.

LIMITATIONS

Confounding by variation in patient-level characteristics and outcomes across registries and regions may have been present. Some factors, such as numbers of first- and second-degree relatives with breast cancer and diagnoses associated with previous benign biopsy results, were not examined.

CONCLUSION

False-positive mammography results and additional imaging are common, particularly for younger women and those with risk factors, whereas biopsies occur less often. Rates of false-negative results are low.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality and National Cancer Institute.

Menopausal hormone therapy and breast cancer mortality: clinical implications

The Women's Health Initiative (WHI) has conducted two randomized, placebo-controlled clinical trials to evaluate the influence of menopausal hormone therapy on chronic disease risk. Estrogen plus progestin was evaluated in 16,608 postmenopausal women without prior hysterectomy during 5.6 years' intervention. In that setting, combined hormone therapy use significantly increased breast cancer incidence and interfered with breast cancer detection. The breast cancers were not limited to estrogen receptor positive, favorable prognosis cancers and were identified at more advanced stage. As a result, deaths from breast cancer were significantly increased by estrogen plus progestin use. While the absolute breast cancer risk for relatively short term (2-4 years) use of combined hormone therapy is small, on a population basis a therapy which nearly doubles deaths from breast cancer requires cautious use. Estrogen alone was evaluated in 10,739 postmenopausal women with prior hysterectomy during 7.1 years' intervention. There was an overall reduction of breast cancer incidence seen with estrogen alone use and a suggestion that the effect on risk was more pronounced in women initiating hormone therapy further from menopause. Nonetheless, women with prior hysterectomy can be assured that short duration estrogen alone use for climacteric symptom management is relatively safe. Neither estrogen plus progestin nor estrogen alone should be used for chronic disease risk reduction. The safety of duration of use on chronic disease risk longer than in the WHI clinical trials is not defined.

Alleviation of plasma homocysteine level by phytoestrogen α-zearalanol might be related to the reduction of cystathionine β-synthase nitration

Hyperhomocysteinemia is strongly associated with cardiovascular diseases. Previous studies have shown that phytoestrogen α-zearalanol can protect cardiovascular system from hyperhomocysteinemia and ameliorate the level of plasma total homocysteine; however, the underlying mechanisms remain to be clarified. The aim of this research is to investigate the possible molecular mechanisms involved in ameliorating the level of plasma homocysteine by α-zearalanol. By the successfully established diet-induced hyperhomocysteinemia rat models, we found that, after α-zearalanol treatment, the activity of cystathionine β-synthase, the key enzyme in homocysteine metabolism, was significantly elevated and level of nitrative stress in liver was significantly reduced. In correlation with this, results also showed a decreased nitration level of cystathionine β-synthase in liver. Together data implied that alleviation of plasma homocysteine level by phytoestrogen α-zearalanol might be related to the reduction of cystathionine β-synthase nitration.

Mammographic performance in a population-based screening program: before, during, and after the transition from screen-film to full-field digital mammography

PURPOSE

To compare performance measures before, during, and after the transition from screen-film mammography (SFM) to full-field digital mammography (FFDM) in a population-based screening program.

MATERIALS AND METHODS

No institutional review board approval was required for this analysis involving anonymized data for women aged 50-69 years enrolled in the Norwegian Breast Cancer Screening Program during 1996-2010. The χ(2) test was used to examine the equality of proportions of recall rates, positive predictive value of recall examinations and of invasive procedures, in addition to rates of screening-detected and interval cancers in women initially screened with SFM and FFDM and for women subsequently screened with SFM after SFM, FFDM after SFM, and FFDM after FFDM.

RESULTS

The recall rate was 3.4% (47 091 of 1 391 188) for SFM and 2.9% (13 130 of 446 172) for FFDM (P < .001). The biopsy rate was 1.4% (19 776 of 1 391 188) for SFM and 1.1% (5108 of 446 172) for FFDM (P < .001). The rate of screening-detected ductal carcinoma in situ was higher (P = .019) while the rate of invasive breast cancer was lower (P < .001) for FFDM compared with those for SFM. The rate of both invasive screening-detected and interval breast cancer remained stable during the transition from SFM to FFDM (when the previous examination was SFM) and after FFDM was firmly established (when the previous examination was FFDM, >25 months after FFDM adoption) (P < .05). The positive predictive value of recall examinations and of invasive procedures increased from 19.3% (4559 of 23 598) and 48.3% (4651 of 9623) to 22.7% (681 of 2995) and 57.5% (689 of 1198), respectively, after adoption of FFDM (P < .001).

CONCLUSION

After the initial transitional phase from SFM to FFDM, population-based screening with FFDM is associated with less harm because of lower recall and biopsy rates and higher positive predictive values after biopsy than screening with SFM.

Fatal breast cancer risk in relation to use of unopposed estrogen and combined hormone therapy

Use of combined hormone therapy (CHT) is associated with increased breast cancer incidence, but it is unclear whether this translates into increased breast cancer mortality. To address this question, we conducted a population-based nested case-control study in Saskatchewan, Canada, where a population-based prescription drug database has existed since 1975. We evaluated fatal breast cancer risk in relation to recency and duration of use of CHT and unopposed estrogen hormone therapy (EHT). A total of 1,288 cases and 12,535 controls were included in the analyses. Exclusive use of EHT was not associated with fatal breast cancer risk, either overall or within categories of recency or duration [odds ratio (OR) for current vs. never use = 1.1; 95 % confidence interval (CI) 0.8-1.3]. Use of CHT (includes women who had also used EHT) was also not associated with fatal breast cancer risk (OR for current vs. never use = 0.9; 95 % CI 0.7-1.3), except for a suggestion of an increased risk with current long-term use. Consistent with prior studies, we observed no increased risk of fatal breast cancer associated with use of EHT. To date only a few studies have evaluated fatal breast cancer risk in relation to use of CHT, and collectively the results are inconsistent.

Phytoestrogen α-Zearalanol attenuates homocysteine-induced apoptosis in human umbilical vein endothelial cells

Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. The enhanced nitrative stress plays an important role in homocysteine-induced endothelial dysfunction. Previous studies have showed that phytoestrogen α -zearalanol alleviated endothelial injury in ovariectomized hyperhomocysteinemic rats; however, the underlying mechanism remains to be clarified. This study was to investigate the effects of α -zearalanol on homocysteine-induced endothelial apoptosis in vitro and explore the possible role of nitrative stress in these effects. Results showed that homocysteine (500  μ mol/L, 24 h) induced the apoptosis of human umbilical vein endothelial cells (HUVECs) obviously, and this effect was significantly attenuated by pretreatment with α -zearalanol (10(-8)~10(-6) mol/L). Moreover, α -zearalanol downregulated proapoptotic protein Bax, upregulated antiapoptotic proteins Bcl-2 and Bcl-XL, and decreased the expression and activity of caspase-9. These findings demonstrated that α -zearalanol could effectively alleviate homocysteine-induced endothelial apoptosis, and this antiapoptosis effect might be related to the inhibition of the intrinsic pathway. Western blot indicated an enhanced 3-nitrotyrosine expression in HUVECs when challenged with homocysteine, which was attenuated by pretreatment with α -zearalanol. This result implied that inhibition of nitrative stress might play a role in the protective effect of α -zearalanol on endothelial cells. Such discovery may shed a novel light on the antiatherogenic activities of α -zearalanol in hyperhomocysteinemia.

Outcomes of screening mammography by frequency, breast density, and postmenopausal hormone therapy

IMPORTANCE

Controversy exists about the frequency women should undergo screening mammography and whether screening interval should vary according to risk factors beyond age.

OBJECTIVE

To compare the benefits and harms of screening mammography frequencies according to age, breast density, and postmenopausal hormone therapy (HT) use.

DESIGN

Prospective cohort.

SETTING

Data collected January 1994 to December 2008 from mammography facilities in community practice that participate in the Breast Cancer Surveillance Consortium (BCSC) mammography registries.

PARTICIPANTS

Data were collected prospectively on 11,474 women with breast cancer and 922,624 without breast cancer who underwent mammography at facilities that participate in the BCSC.

MAIN OUTCOMES AND MEASURES

We used logistic regression to calculate the odds of advanced stage (IIb, III, or IV) and large tumors (>20 mm in diameter) and 10-year cumulative probability of a false-positive mammography result by screening frequency, age, breast density, and HT use. The main predictor was screening mammography interval.

RESULTS

Mammography biennially vs annually for women aged 50 to 74 years does not increase risk of tumors with advanced stage or large size regardless of women's breast density or HT use. Among women aged 40 to 49 years with extremely dense breasts, biennial mammography vs annual is associated with increased risk of advanced-stage cancer (odds ratio [OR], 1.89; 95% CI, 1.06-3.39) and large tumors (OR, 2.39; 95% CI, 1.37-4.18). Cumulative probability of a false-positive mammography result was high among women undergoing annual mammography with extremely dense breasts who were either aged 40 to 49 years (65.5%) or used estrogen plus progestogen (65.8%) and was lower among women aged 50 to 74 years who underwent biennial or triennial mammography with scattered fibroglandular densities (30.7% and 21.9%, respectively) or fatty breasts (17.4% and 12.1%, respectively).

CONCLUSIONS AND RELEVANCE

Women aged 50 to 74 years, even those with high breast density or HT use, who undergo biennial screening mammography have similar risk of advanced-stage disease and lower cumulative risk of false-positive results than those who undergo annual mammography. When deciding whether to undergo mammography, women aged 40 to 49 years who have extremely dense breasts should be informed that annual mammography may minimize their risk of advanced-stage disease but the cumulative risk of false-positive results is high.

Progestogens used in postmenopausal hormone therapy: differences in their pharmacological properties, intracellular actions, and clinical effects

The safety of progestogens as a class has come under increased scrutiny after the publication of data from the Women's Health Initiative trial, particularly with respect to breast cancer and cardiovascular disease risk, despite the fact that only one progestogen, medroxyprogesterone acetate, was used in this study. Inconsistency in nomenclature has also caused confusion between synthetic progestogens, defined here by the term progestin, and natural progesterone. Although all progestogens by definition have progestational activity, they also have a divergent range of other properties that can translate to very different clinical effects. Endometrial protection is the primary reason for prescribing a progestogen concomitantly with postmenopausal estrogen therapy in women with a uterus, but several progestogens are known to have a range of other potentially beneficial effects, for example on the nervous and cardiovascular systems. Because women remain suspicious of the progestogen component of postmenopausal hormone therapy in the light of the Women's Health Initiative trial, practitioners should not ignore the potential benefits to their patients of some progestogens by considering them to be a single pharmacological class. There is a lack of understanding of the differences between progestins and progesterone and between individual progestins differing in their effects on the cardiovascular and nervous systems, the breast, and bone. This review elucidates the differences between the substantial number of individual progestogens employed in postmenopausal hormone therapy, including both progestins and progesterone. We conclude that these differences in chemical structure, metabolism, pharmacokinetics, affinity, potency, and efficacy via steroid receptors, intracellular action, and biological and clinical effects confirm the absence of a class effect of progestogens.

Estrogen plus progestin and breast cancer incidence and mortality in the Women's Health Initiative Observational Study

BACKGROUND

In the Women's Health Initiative (WHI) randomized trial, estrogen plus progestin increased both breast cancer incidence and mortality. In contrast, most observational studies associate estrogen plus progestin with favorable prognosis breast cancers. To address differences, a cohort of WHI observational study participants with characteristics similar to the WHI clinical trial was studied.

METHODS

We identified 41 449 postmenopausal women with no prior hysterectomy and mammogram negative within 2 years who were either not hormone users (n = 25 328) or estrogen and progestin users (n = 16 121). Multivariable-adjusted Cox proportional hazard regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CI). All statistical tests were two-sided.

RESULTS

After a mean of 11.3 (SD = 3.1) years, with 2236 breast cancers, incidence was higher in estrogen plus progestin users than in nonusers (0.60% vs 0.42%, annualized rate, respectively; HR = 1.55, 95% CI = 1.41 to 1.70, P < .001). Women initiating hormone therapy closer to menopause had higher breast cancer risk with linear diminishing influence as time from menopause increased (P < .001). Survival after breast cancer, measured from diagnosis, was similar in combined hormone therapy users and nonusers (HR = 1.03, 95% CI = 0.79 to 1.35). On a population basis, there were somewhat more deaths from breast cancer, measured from cohort entry (HR = 1.32, 95% CI = 0.90 to 1.93, P = .15), and more all-cause deaths after breast cancer (HR = 1.65, 95% CI = 1.29 to 2.12, P < .001) in estrogen plus progestin users than in nonusers.

CONCLUSIONS

Consistent with WHI randomized trial findings, estrogen plus progestin use is associated with increased breast cancer incidence. Because prognosis after diagnosis on combined hormone therapy is similar to that of nonusers, increased breast cancer mortality can be expected.

Ductal carcinoma in situ: what the pathologist needs to know and why

Ductal carcinoma in situ is a proliferation of malignant epithelial cells confined to the ductolobular system of the breast. It is considered a pre-cursor lesion for invasive breast cancer and when identified patients are treated with some combination of surgery, +/− radiation therapy, and +/adjuvant tamoxifen. However, no good biomarkers exist that can predict with accuracy those cases of DCIS destined to progress to invasive disease or once treated those patients that are likely to suffer a recurrence; thus, in the era of screening mammography it seems likely that many patients with DCIS are overtreated. This paper details the parameters that should be included in a pathology report for a case of DClS with some explanations as to their importance for good clinical decision making.

Effects of menopausal hormone therapy on ductal carcinoma in situ of the breast

Post-menopausal hormone therapy with estrogen plus progestin is consistently reported to be associated with an increased risk of invasive breast cancer. However, findings on an association between hormone use and ductal carcinoma in situ of the breast (DCIS), a possible precursor lesion of invasive breast cancer, are sparse and inconsistent. Women's Health Initiative data were used to assess the effects of hormone therapy on the risk of DCIS in two clinical trials of hormone therapy (16,276 women enrolled in the trial of daily conjugated equine estrogens plus medroxyprogesterone acetate (CEE + MPA) vs placebo; 10,187 women enrolled in the trial of CEE-alone vs placebo). The effects of hormone therapy on DCIS in clinical trial participants were assessed during the intervention, post-intervention, and entire followup periods, and in the observational study (OS; 30,421 CEE + MPA users and non-users and 18,657 CEE-alone users and non-users who met eligibility criteria similar to the clinical trial). Compared to placebo, CEE + MPA was non-significantly associated with higher risk of DCIS over approximate average of 11 years of follow-up (HR = 1.23; 95 % CI: 0.91-1.64). No statistical difference was detected between intervention and post-intervention phases (p = 0.32). Corresponding OS results supported an increased risk for DCIS in CEE + MPA users compared to women who were non-users (HR = 1.65; 95 % CI: 1.25-2.19) after adjusting for potential confounders. There was no clear association between CEE-alone use and risk of DCIS. CEE-alone trial data showed that the risk of DCIS was non-significantly lower in the treatment than in the placebo group, while analysis of the corresponding OS showed a non-significantly higher risk of DCIS in the CEE-alone users than non-users. Our analysis suggests that combined estrogen plus progestin use in post-menopausal women may increase risk of DCIS. Whether estrogen-alone use is associated with DCIS requires further investigation.

[Does molecular biology play any role in ductal carcinoma in situ?]

The natural history of ductal carcinoma in situ (DCIS) is not fully elucidated, but it is recognized that DCIS is the true precursor of invasive carcinoma. Studies could show that DCIS is as heterogeneous as invasive ductal carcinoma, yet, they were unable to predict which DCIS will progress to invasion. Several biomarkers were also demonstrated to have a certain prognostic value. However, except for estrogen receptors and HER2, biomarkers are not yet widely used in clinical practice since their predictive value has not proven to be better than the grade and the classical classifying systems of DCIS. Identifying biomarkers for risk of invasiveness in DCIS could be of great value to help high risk patients through the management of their disease and to avoid overtreatment in low risk patients.

Mammographic density and estimation of breast cancer risk in intermediate risk population

It is not clear to what extent mammographic density represents a risk factor for breast cancer among women with moderate risk for disease. We conducted a population-based study to estimate the independent effect of breast density on breast cancer risk and to evaluate the potential of breast density as a marker of risk in an intermediate risk population. From November 2006 to April 2009, data that included American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) breast density categories and risk information were collected on 52,752 women aged 50-69 years without previously diagnosed breast cancer who underwent screening mammography examination. A total of 257 screen-detected breast cancers were identified. Logistic regression was used to assess the effect of breast density on breast carcinoma risk and to control for other risk factors. The risk increased with density and the odds ratio for breast cancer among women with dense breast (heterogeneously and extremely dense breast), was 1.9 (95% confidence interval, 1.3-2.8) compared with women with almost entirely fat breasts, after adjustment for age, body mass index, age at menarche, age at menopause, age at first childbirth, number of live births, use of oral contraceptive, family history of breast cancer, prior breast procedures, and hormone replacement therapy use that were all significantly related to breast density (p < 0.001). In multivariate model, breast cancer risk increased with age, body mass index, family history of breast cancer, prior breast procedure and breast density and decreased with number of live births. Our finding that mammographic density is an independent risk factor for breast cancer indicates the importance of breast density measurements for breast cancer risk assessment also in moderate risk populations.

Multiple nuclear receptor signaling pathways mediate the actions of synthetic progestins in target cells

Synthetic progestins are used clinically to treat a variety of women's health issues. Although progestins are designed to signal through the progesterone receptor (PR) to elicit specific pharmacological effects, they can also variably bind to and influence the activity of other nuclear receptors within target tissues, particularly the androgen and glucocorticoid receptors and, in some cases, they regulate mineralocorticoid and estrogen receptors. This article reviews current knowledge on progestin cross-talk to nuclear receptors other than PR, their resultant effect on receptor function in different in vitro models and the potential consequences of this activity for breast, ovarian and endometrial cancer. The impact of cell and tissue context, assay type, steroid metabolism and hormonal milieu in determining progestin-mediated activity are also presented. Collectively this review highlights the complexity of progestin action and the need for consideration of multiple mechanisms that act in concert to influence their ultimate biological activity.

Changing concepts: Menopausal hormone therapy and breast cancer

Hormone therapy is still used by millions of women for menopausal symptoms. Concerns regarding hormone therapy and breast cancer were initially based on case reports and retrospective case-control studies. However, recent results from large prospective cohort studies and the Women's Health Initiative (WHI) randomized placebo-controlled hormone therapy trials have substantially changed concepts regarding how estrogen alone and estrogen plus progestin influence breast cancer. The preponderance of observational studies suggested that estrogen alone and estrogen plus progestin both increased the risk of breast cancer, with cancers commonly diagnosed at an early stage. However, substantially different results emerged from the WHI randomized hormone therapy trials. In the WHI trial evaluating estrogen plus progestin in postmenopausal women with an intact uterus, combined hormone therapy statistically significantly increased the risk of breast cancer and hindered breast cancer detection, leading to delayed diagnosis and a statistically significant increase in breast cancer mortality. By contrast, estrogen alone use by postmenopausal women with prior hysterectomy in the WHI trial did not substantially interfere with breast cancer detection and statistically significantly decreased the risk of breast cancer. Differential mammography usage patterns may explain differences between observational study and randomized trial results. In clinical practice, hormone therapy users have mammograms more frequently than nonusers, leading to more and earlier stage cancer detection. By contrast, in the WHI randomized trials, mammogram frequency was protocol mandated and balanced between comparison groups. Currently, the different effects of estrogen plus progestin vs estrogen alone on breast cancer are not completely understood.

Postmenopausal hormone therapy and ductal carcinoma in situ: a population-based case-control study

BACKGROUND AND AIM

The relationship between hormone therapy (HT) and invasive breast cancer has been extensively investigated, but the relationship between HT and in situ breast cancer has received relatively little attention. We examined the relationship between HT and ductal carcinoma in situ (DCIS) among postmenopausal women who participated in a population-based case-control study in Connecticut, USA.

METHODS

This analysis included 1179 post-menopausal women (603 controls and 576 cases), who comprised a subset of a population-based case-control study that included all incident cases of breast carcinoma in situ (BCIS) in Connecticut and frequency-matched controls by 5-year age intervals.

RESULTS

We found no association between DCIS and ever use of any HT (adjusted odds ratio (OR)=0.85, 95% confidence interval (CI): 0.65-1.11); of estrogen alone (adjusted OR=0.93; 95% CI: 0.68-1.29) or of estrogen and progesterone (adjusted OR=0.75; 95% CI: 0.52-1.08). There was also no association between DCIS and current use of these hormones. In addition, estimated risk of DCIS did not increase with duration of use of these preparations.

CONCLUSIONS

These results add to a small literature that remains inconclusive. To determine whether HT poses risk of in situ breast cancer, larger studies with greater power and precise control of important covariates (e.g., mammography screening) are needed, as are meta-analyses of available data.

Screening mammography use among current, former, and never hormone therapy users may not explain recent declines in breast cancer incidence

BACKGROUND

Screening mammography and invasive breast cancer and ductal carcinoma in situ (DCIS) rates recently declined in the United States; screening mammography declines among former hormone therapy (HT) users may be an important contributor. We longitudinally examined women and compared mammography use and cancer rates by HT use [current, former, and never users of estrogen + progestin (EPT) and estrogen only (ET)].

METHODS

We studied 163,490 unique women aged 50-79 years enrolled in Group Health (Washington State) between 1994-2009. Electronic data identified HT dispensing, mammography use and incident breast cancer diagnosis. We calculated age-adjusted screening compliance as a time-varying variable (screened-within-the-past-26 months, yes/no).

RESULTS

Before 2002, screening compliance differed significantly by HT with current EPT users having the highest rates (83%) followed by former EPT (77%), current ET (77%), former ET (72%), and never users (56%). After 2002, screening was high (∼81%) among current and former EPT and ET users and significantly increased among never users (∼62%). Invasive breast cancer rates significantly decreased over the whole study period (P(trend) ≤ 0.05) for all HT users, except EPT current users (P(trend) = 0.68); DCIS rates did not change in any group.

CONCLUSIONS

Differential screening mammography rates by HT use do not explain invasive breast cancer incidence declines. Our data suggest discontinuing HT has an immediate effect on breast cancer rates, lending support to the mechanism that cessation leads to tumor regression.

IMPACT

Studies examining the influence of a changing exposure in relation to outcomes should account for varying exposures, individuals' characteristics, as well as screening methods and frequency.

Comparative effectiveness of digital versus film-screen mammography in community practice in the United States: a cohort study

BACKGROUND

Few studies have examined the comparative effectiveness of digital versus film-screen mammography in U.S. community practice.

OBJECTIVE

To determine whether the interpretive performance of digital and film-screen mammography differs.

DESIGN

Prospective cohort study.

SETTING

Mammography facilities in the Breast Cancer Surveillance Consortium.

PARTICIPANTS

329,261 women aged 40 to 79 years underwent 869 286 mammograms (231 034 digital; 638 252 film-screen).

MEASUREMENTS

Invasive cancer or ductal carcinoma in situ diagnosed within 12 months of a digital or film-screen examination and calculation of mammography sensitivity, specificity, cancer detection rates, and tumor outcomes.

RESULTS

Overall, cancer detection rates and tumor characteristics were similar for digital and film-screen mammography, but the sensitivity and specificity of each modality varied by age, tumor characteristics, breast density, and menopausal status. Compared with film-screen mammography, the sensitivity of digital mammography was significantly higher for women aged 60 to 69 years (89.9% vs. 83.0%; P = 0.014) and those with estrogen receptor-negative cancer (78.5% vs. 65.8%; P = 0.016); borderline significantly higher for women aged 40 to 49 years (82.4% vs. 75.6%; P = 0.071), those with extremely dense breasts (83.6% vs. 68.1%; P = 0.051), and pre- or perimenopausal women (87.1% vs. 81.7%; P = 0.057); and borderline significantly lower for women aged 50 to 59 years (80.5% vs. 85.1%; P = 0.097). The specificity of digital and film-screen mammography was similar by decade of age, except for women aged 40 to 49 years (88.0% vs. 89.7%; P < 0.001).

LIMITATION

Statistical power for subgroup analyses was limited.

CONCLUSION

Overall, cancer detection with digital or film-screen mammography is similar in U.S. women aged 50 to 79 years undergoing screening mammography. Women aged 40 to 49 years are more likely to have extremely dense breasts and estrogen receptor-negative tumors; if they are offered mammography screening, they may choose to undergo digital mammography to optimize cancer detection.

PRIMARY FUNDING SOURCE

National Cancer Institute.

Health outcomes after stopping conjugated equine estrogens among postmenopausal women with prior hysterectomy: a randomized controlled trial

CONTEXT

The Women's Health Initiative Estrogen-Alone Trial was stopped early after a mean of 7.1 years of follow-up because of an increased risk of stroke and little likelihood of altering the balance of risk to benefit by the planned trial termination date. Postintervention health outcomes have not been reported.

OBJECTIVE

To examine health outcomes associated with randomization to treatment with conjugated equine estrogens (CEE) among women with prior hysterectomy after a mean of 10.7 years of follow-up through August 2009.

DESIGN, SETTING, AND PARTICIPANTS

The intervention phase was a double-blind, placebo-controlled, randomized clinical trial of 0.625 mg/d of CEE compared with placebo in 10,739 US postmenopausal women aged 50 to 79 years with prior hysterectomy. Follow-up continued after the planned trial completion date among 7645 surviving participants (78%) who provided written consent.

MAIN OUTCOME MEASURES

The primary outcomes were coronary heart disease (CHD) and invasive breast cancer. A global index of risks and benefits included these primary outcomes plus stroke, pulmonary embolism, colorectal cancer, hip fracture, and death.

RESULTS

The postintervention risk (annualized rate) for CHD among women assigned to CEE was 0.64% compared with 0.67% in the placebo group (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.75-1.25), 0.26% vs 0.34%, respectively, for breast cancer (HR, 0.75; 95% CI, 0.51-1.09), and 1.47% vs 1.48%, respectively, for total mortality (HR, 1.00; 95% CI, 0.84-1.18). The risk of stroke was no longer elevated during the postintervention follow-up period and was 0.36% among women receiving CEE compared with 0.41% in the placebo group (HR, 0.89; 95% CI, 0.64-1.24), the risk of deep vein thrombosis was lower at 0.17% vs 0.27%, respectively (HR, 0.63; 95% CI, 0.41-0.98), and the risk of hip fracture did not differ significantly and was 0.36% vs 0.28%, respectively (HR, 1.27; 95% CI, 0.88-1.82). Over the entire follow-up, lower breast cancer incidence in the CEE group persisted and was 0.27% compared with 0.35% in the placebo group (HR, 0.77; 95% CI, 0.62-0.95). Health outcomes were more favorable for younger compared with older women for CHD (P = .05 for interaction), total myocardial infarction (P = .007 for interaction), colorectal cancer (P = .04 for interaction), total mortality (P = .04 for interaction), and global index of chronic diseases (P = .009 for interaction).

CONCLUSIONS

Among postmenopausal women with prior hysterectomy followed up for 10.7 years, CEE use for a median of 5.9 years was not associated with an increased or decreased risk of CHD, deep vein thrombosis, stroke, hip fracture, colorectal cancer, or total mortality. A decreased risk of breast cancer persisted.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00000611.

Ductal carcinoma in situ: risk factors and impact of screening

BACKGROUND

The National Institutes of Health Office of Medical Applications of Research commissioned a structured literature review on the incidence of ductal carcinoma in situ (DCIS) as a background paper for the State of the Science Conference on Diagnosis and Management of DCIS.

METHODS

Published studies were abstracted from MEDLINE and other sources. We include articles published through January 31, 2009; 92 publications were abstracted.

RESULTS

DCIS incidence rose from 1.87 per 100,000 in 1973-1975 to 32.5 per 100,000 in 2005. Increases in incidence were greatest in tumors without comedo necrosis. Incidence increased in all ages but more in women older than 50 years. Increased use of mammography explains some but not all of the increased incidence. Risk factors for incident DCIS include older age and positive family history. Whereas tamoxifen prevents both invasive breast cancer and DCIS, raloxifene is associated with decreased invasive breast cancer but not decreased DCIS.

CONCLUSIONS

Scientific questions deserving further investigation include the relationship between mammography use and DCIS incidence and the role of chemoprevention for reducing the incidence of DCIS and invasive breast cancer.

The contribution of postmenopausal hormone use cessation to the declining incidence of breast cancer

The striking decline in United States breast cancer incidence since 2002 has been widely attributed to a reduction in postmenopausal hormone use, yet very little analysis has been conducted to quantify the contribution of changes in hormone use to the declining trend. We used literature-based estimates of the relative risk and the changing prevalence of hormone use to estimate the impact of hormone use on the decline in breast cancer incidence between 2002 and 2003 among women aged 40-79. For the base case of a 44% decline in hormone use and a relative risk for current use of 1.5, we estimated that 43% of the decline in incidence was attributable to hormone use. By exploring a range of parameter values, we found that high, unlikely values of the relative risk (i.e., ≥ 2.25) and/or the percent decline in hormone use (i.e., ≥ 75%) would be required to account for 100% of the observed decline in breast cancer incidence. We conclude that hormone use is unlikely to account for more than half of the observed decline in breast cancer incidence between 2002 and 2003. Further efforts are needed to quantify the potential contributions of other factors, such as the plateau in screening mammography utilization.

Changes in invasive breast cancer and ductal carcinoma in situ rates in relation to the decline in hormone therapy use

PURPOSE

To assess trends in invasive breast cancer and ductal carcinoma in situ (DCIS) incidence in association with changes in hormone therapy (HT) use in regular mammography screeners.

METHODS

We included 2,071,814 screening mammography examinations performed between January 1997 and December 2006 on 696,385 women age 40 to 79 years; 9,586 breast cancers were diagnosed within 12 months of a screening examination. We calculated adjusted annual rates (mammogram level) for prevalent HT use, incident invasive breast cancer (overall and by tumor histology and estrogen receptor [ER] status), and incident DCIS.

RESULTS

After a precipitous decrease in HT use in 2002, the incidence of invasive breast cancer decreased significantly in 2002 to 2006 among women age 50 to 69 years (P(trend(2002-2006)) = .005) and 70 to 79 years (P(trend(2002-2006)) = .003) but not in women age 40 to 49 years (P(trend(2002-2006)) = .45). DCIS rates significantly decreased in women age 50 to 69 years after 2002 (P(trend(2002-2006)) = .02). Invasive ductal tumors significantly declined in women age 50 to 69 years and 70 to 79 years in 2002 to 2006. In women age 50 to 69 years, invasive lobular and ER-positive cancer rates declined steadily in 2002 to 2005 (P(trend(2002-2005)) = .02 and .03, respectively), but an elevated rate in 2006 rendered the overall trend nonsignificant (P(trend(2002-2006)) = .89 and .91, respectively).

CONCLUSION

In parallel to the sharp decline in HT use in women undergoing regular mammography screening, invasive breast cancer rates decreased in women age 50 to 69 and 70 to 79 years after 2002, and DCIS rates decreased in women age 50 to 69 years, consistent with evidence that HT cessation reduces breast cancer risk. However, the decrease in incidence may have started to level off in 2006; this finding has not been uniformly reported in other populations, warranting further investigation.

Estrogen plus progestin and breast cancer incidence and mortality in postmenopausal women

CONTEXT

In the Women's Health Initiative randomized, placebo-controlled trial of estrogen plus progestin, after a mean intervention time of 5.6 (SD, 1.3) years (range, 3.7-8.6 years) and a mean follow-up of 7.9 (SD, 1.4) years, breast cancer incidence was increased among women who received combined hormone therapy. Breast cancer mortality among participants in the trial has not been previously reported.

OBJECTIVE

To determine the effects of therapy with estrogen plus progestin on cumulative breast cancer incidence and mortality after a total mean follow-up of 11.0 (SD, 2.7) years, through August 14, 2009.

DESIGN, SETTING, AND PARTICIPANTS

A total of 16,608 postmenopausal women aged 50 to 79 years with no prior hysterectomy from 40 US clinical centers were randomly assigned to receive combined conjugated equine estrogens, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, or placebo pill. After the original trial completion date (March 31, 2005), reconsent was required for continued follow-up for breast cancer incidence and was obtained from 12,788 (83%) of the surviving participants.

MAIN OUTCOME MEASURES

Invasive breast cancer incidence and breast cancer mortality.

RESULTS

In intention-to-treat analyses including all randomized participants and censoring those not consenting to additional follow-up on March 31, 2005, estrogen plus progestin was associated with more invasive breast cancers compared with placebo (385 cases [0.42% per year] vs 293 cases [0.34% per year]; hazard ratio [HR], 1.25; 95% confidence interval [CI], 1.07-1.46; P = .004). Breast cancers in the estrogen-plus-progestin group were similar in histology and grade to breast cancers in the placebo group but were more likely to be node-positive (81 [23.7%] vs 43 [16.2%], respectively; HR, 1.78; 95% CI, 1.23-2.58; P = .03). There were more deaths directly attributed to breast cancer (25 deaths [0.03% per year] vs 12 deaths [0.01% per year]; HR, 1.96; 95% CI, 1.00-4.04; P = .049) as well as more deaths from all causes occurring after a breast cancer diagnosis (51 deaths [0.05% per year] vs 31 deaths [0.03% per year]; HR, 1.57; 95% CI, 1.01-2.48; P = .045) among women who received estrogen plus progestin compared with women in the placebo group.

CONCLUSIONS

Estrogen plus progestin was associated with greater breast cancer incidence, and the cancers are more commonly node-positive. Breast cancer mortality also appears to be increased with combined use of estrogen plus progestin.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00000611.

Socioeconomic disparities in the decline in invasive breast cancer incidence

Breast cancer incidence in the United States has declined dramatically since the year 2002. To improve our understanding of the underlying factors driving breast cancer trends, we explored potential socioeconomic disparities in the recent decline in incidence. We examined the decline in breast cancer incidence according to county-level socioeconomic indicators using data from the Surveillance, Epidemiology and End Results (SEER) program. Since socioeconomic status is associated with mammography screening, we also examined the relation between incidence of ductal carcinoma in situ (DCIS; a strong marker of mammography utilization) and the decline in invasive breast cancer. The reduction in invasive breast cancer incidence between 1998-2001 and 2003-2006 in the SEER 9 registries was greatest among women living in counties with higher median household income (-16% change for > or = $85,000 vs. -4% for <$35,000; P(trend) < 0.01) and a higher percentage of adults aged 25 years or older with a bachelor's degree (-13% change for > or = 40% vs. -8% for <15%; P(trend) < 0.01). Counties with higher DCIS incidence during 1985-2001 had a larger decrease in invasive breast cancer incidence (absolute decrease 1.7 percentage points greater per 5 per 100,000 increase in DCIS incidence; P = 0.01). This association was present for both ER-positive and ER-negative invasive cancers (P < 0.05). In summary, the decline in breast cancer incidence has been largest in areas with high socioeconomic status and high screening utilization rates. These results are consistent with the hypothesis that a saturation of screening mammography utilization contributed to the overall decline in breast cancer incidence.

Breast cancer risk by breast density, menopause, and postmenopausal hormone therapy use

PURPOSE

We determined whether the association between breast density and breast cancer risk and cancer severity differs according to menopausal status and postmenopausal hormone therapy (HT) use.

METHODS

We collected data on 587,369 women who underwent 1,349,027 screening mammography examinations; 14,090 women were diagnosed with breast cancer. We calculated 5-year breast cancer risk from a survival model for subgroups of women classified by their Breast Imaging Reporting and Data System (BIRADS) breast density, age, menopausal status, and current HT use, assuming a body mass index of 25 kg/m(2). Odds of advanced (ie, IIb, III, IV) versus early (ie, I, IIa) stage invasive cancer was calculated according to BIRADS density.

RESULTS

Breast cancer risk was low among women with low density (BIRADS-1): women age 55 to 59 years, 5-year risk was 0.8% (95% CI, 0.6 to 0.9%) for non-HT users and 0.9% (95% CI, 0.7% to 1.1%) for estrogen and estrogen plus progestin users. Breast cancer risk was high among women with very high density (BIRADS-4), particularly estrogen plus progestin users: women age 55 to 59 years, 5-year risk was 2.4% (95% CI, 2.0% to 2.8%) for non-HT users, 3.0% (95% CI, 2.6% to 3.5%) for estrogen users, and 4.2% (95% CI, 3.7% to 4.6%) for estrogen plus progestin users. Advanced-stage breast cancer risk was increased 1.7-fold for postmenopausal HT users who had very high density (BIRADS-4) compared to those with average density (BIRADS-2).

CONCLUSION

Postmenopausal women with high breast density are at increased risk of breast cancer and should be aware of the added risk of taking HT, especially estrogen plus progestin.

Risk factors for ductal, lobular, and mixed ductal-lobular breast cancer in a screening population

BACKGROUND

Biological distinctions between histologic subtypes of breast cancer suggest etiologic differences, although few studies have been powered to examine such differences. We compared associations between several factors and risk of ductal, lobular, and mixed ductal-lobular breast cancers.

METHODS

We used risk factor data from the Breast Cancer Surveillance Consortium for 3,331,744 mammograms on 1,211,238 women, including 19,119 women diagnosed with invasive breast cancer following mammography (n = 14,818 ductal, 1,602 lobular, and 1,601 mixed ductal-lobular). Histologic subtype-specific risk factor associations were evaluated using Cox regression.

RESULTS

Significant positive associations with family history and breast density were similar across subtypes. Hormone therapy use was associated with increased risk of all subtypes, but was most strongly associated with lobular cancer [hazard ratio (HR) = 1.46; 95% confidence interval (CI), 1.25-1.70]. Relative to nulliparous women, parous women had lower risk of ductal and mixed but not lobular cancers (HR = 0.80; 95% CI, 0.76-0.84; HR = 0.79; 95% CI, 0.68-0.93; HR = 0.96; 95% CI, 0.81-1.15, respectively). Late age at first birth was associated with increased risk of all subtypes.

CONCLUSIONS

Similarities in risk factor associations with ductal, lobular, and mixed breast cancer subtypes were more pronounced than differences. Distinctions between subtype-specific associations were limited to analyses of hormone therapy use and reproductive history.

IMPACT

The results of this study indicate that the strongest risk factors for breast cancer overall (that is, family history and breast density) are not histologic subtype specific. Additional studies are needed to better characterize subtype-specific associations with genetic, hormonal, and nonhormonal factors.

Hormone therapy and fatal breast cancer

PURPOSE

Among unanswered questions is whether menopausal use of estrogen therapy (ET) or estrogen-plus-progestin therapy (CHT) increases risk of developing fatal breast cancer i.e., developing and dying of breast cancer. Using a population-based case-control design, we estimated incidence rate ratios of fatal breast cancer in postmenopausal hormone therapy (HT) users compared to non-users by type, duration, and recency of HT use.

METHODS

HT use prior to breast cancer diagnosis in 278 women who died of breast cancer within 6 years of diagnosis (cases) was compared with use in 2224 controls never diagnosed with breast cancer using conditional logistic regression. Measures taken to address potential bias and confounding inherent in case-control studies included collecting and adjusting for detailed data on demographic and other factors potentially associated both with HT use and breast cancer.

RESULTS

Fifty-six per cent of cases and 68% of controls reported HT use. Among current 3+ year HT users, odds ratios and 95% confidence intervals for death were 0.83 (0.50, 1.38) and 0.69 (0.44, 1.09), respectively, for exclusive use of CHT or of ET, and were 0.94 (0.59, 1.48) and 0.70 (0.45, 1.07) for any use of CHT or of ET regardless of other hormone use.

CONCLUSION

Point estimates suggest no increased risk of fatal breast cancer with HT use, although 50% increases in risk in longer-term current CHT users cannot be ruled out.

Recent trends in hormone therapy utilization and breast cancer incidence rates in the high incidence population of Marin County, California

Background

Recent declines in invasive breast cancer have been reported in the US, with many studies linking these declines to reductions in the use of combination estrogen/progestin hormone therapy (EPHT). We evaluated the changing use of postmenopausal hormone therapy, mammography screening rates, and the decline in breast cancer incidence specifically for Marin County, California, a population with historically elevated breast cancer incidence rates.

Methods

The Marin Women's Study (MWS) is a community-based, prospective cohort study launched in 2006 to monitor changes in breast cancer, breast density, and personal and biologic risk factors among women living in Marin County. The MWS enrolled 1,833 women following routine screening mammography between October 2006 and July 2007. Participants completed a self-administered questionnaire that included items regarding historical hormone therapy regimen (estrogen only, progesterone only, EPHT), age of first and last use, total years of use, and reason(s) for stopping, as well as information regarding complementary hormone use. Questionnaire items were analyzed for 1,083 non-Hispanic white participants ages 50 and over. Breast cancer incidence rates were assessed overall and by tumor histology and estrogen receptor (ER) status for the years 1990-2007 using data from the Northern California Surveillance, Epidemiology and End Results (SEER) cancer registry.

Results

Prevalence of EPHT use among non-Hispanic white women ages 50 and over declined sharply from 21.2% in 1998 to 6.7% by 2006-07. Estrogen only use declined from 26.9% in 1998 to 22.4% by 2006-07. Invasive breast cancer incidence rates declined 33.4% between 2001 and 2004, with drops most pronounced for ER+ cancers. These rate reductions corresponded to declines of about 50 cases per year, consistent with population attributable fraction estimates for EPHT-related breast cancer. Self-reported screening mammography rates did not change during this period. Use of alternative or complementary agents did not differ significantly between ever and never hormone users. Of women who reported stopping EPHT in the past 5 years, 60% cited "health risks" or "news reports" as their primary reasons for quitting.

Conclusion

A dramatic reduction in EPHT use was followed temporally by a significant reduction in invasive and ER+ breast cancer rates among women living in Marin County, California.

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.