Racial differences in mammographic breast density

A Prospective Multicenter Study on the Additive Value of Contrast-Enhanced Ultrasound for Biopsy Decision of Ultrasound BI-RADS 4 Breast Lesions

OBJECTIVE

The main aim of this study was to determine whether the use of contrast-enhanced ultrasound (CEUS) could improve the categorization of suspicious breast lesions based on the Breast Imaging Reporting and Data System (BI-RADS), thereby reducing the number of benign breast lesions referred for biopsy.

METHODS

This prospective study, conducted between January 2017 and December 2018, enrolled consenting patients from eight teaching hospitals in China, who had been diagnosed with solid breast lesions classified as BI-RADS 4 using conventional ultrasound. CEUS was performed within 1 wk of diagnosis for reclassification of breast lesions. Histopathological results obtained from core needle biopsies or surgical excision samples served as the reference standard. The simulated biopsy rate and cancer-to-biopsy yield were used to compare the accuracy of CEUS and conventional ultrasound (US).

RESULTS

Among the 1490 lesions diagnosed as BI-RADS 4 with conventional ultrasound, 486 malignant and 1004 benign lesions were confirmed based on histology. Following CEUS, 2, 395, and 211 lesions were reclassified as CEUS-based BI-RADS 2, 3, and 5, respectively, while 882 (59%) remained as BI-RADS 4. The actual cancer-to-biopsy yield based on US was 32.6%, which increased to 43.4% when CEUS-based BI-RADS 4A was used as the cut-off point to recommend biopsy. The simulated biopsy rate decreased to 73.4%. Overall, in this preselected BI-RADS 4 population, only 2.5% (12/486) of malignant lesions would have been miscategorized as BI-RADS 3 using CEUS-based reclassification. The diagnostic accuracy, sensitivity, and specificity of contrast-enhanced ultrasound reclassification were 57.65%, 97.53%, and 38.35%, respectively.

CONCLUSION

Our collective findings indicate that CEUS is a valuable tool in further triage of BI-RADS category 4 lesions and facilitates a reduction in the number of biopsies while increasing the cancer-to-biopsy yield.

Reproductive risk factors for breast cancer and association with novel breast density measurements among Hispanic, Black, and White women

PURPOSE

There are differences in the distributions of breast cancer incidence and risk factors by race and ethnicity. Given the strong association between breast density and breast cancer, it is of interest describe racial and ethnic variation in the determinants of breast density.

METHODS

We characterized racial and ethnic variation in reproductive history and several measures of breast density for Hispanic (n = 286), non-Hispanic Black (n = 255), and non-Hispanic White (n = 1694) women imaged at a single hospital. We quantified associations between reproductive factors and percent volumetric density (PVD), dense volume (DV), non-dense volume (NDV), and a novel measure of pixel intensity variation (V) using multivariable-adjusted linear regression, and tested for statistical heterogeneity by race and ethnicity.

RESULTS

Reproductive factors most strongly associated with breast density were age at menarche, parity, and oral contraceptive use. Variation by race and ethnicity was most evident for the associations between reproductive factors and NDV (minimum p-heterogeneity:0.008) and V (minimum p-heterogeneity:0.004) and least evident for PVD (minimum p-heterogeneity:0.042) and DV (minimum p-heterogeneity:0.041).

CONCLUSION

Reproductive choices, particularly those related to childbearing and oral contraceptive use, may contribute to racial and ethnic variation in breast density.

Atypical Ductal Hyperplasia of the Breast on Core Needle Biopsy: Risk of Malignant Upgrade On Surgical Excision

Purpose

This study identified factors predicting malignant upgrade for atypical ductal hyperplasia (ADH) diagnosed on core-needle biopsy (CNB) and developed a nomogram to facilitate evidence-based decision making.

Methods

This retrospective analysis included women diagnosed with ADH at the National Cancer Centre Singapore (NCCS) in 2010–2015. Cox proportional hazards regression was used to identify clinical, radiological, and histological factors associated with malignant upgrade. A nomogram was constructed using variables with the strongest associations in multivariate analysis. Multivariable logistic regression coefficients were used to estimate the predicted probability of upgrade for each factor combination.

Results

Between 2010 and 2015, 238,122 women underwent mammographic screening under the National Breast Cancer Screening Program. Among 29,564 women recalled, 5,971 CNBs were performed. Of these, 2,876 underwent CNBs at NCCS, with 88 patients (90 lesions) diagnosed with ADH and 26 lesions upgraded to breast malignancy on excision biopsy. In univariate analysis, factors associated with malignant upgrade were the presence of a mass on ultrasound (p = 0.018) or mammography (p = 0.026), microcalcifications (p = 0.047), diffuse microcalcification distribution (p = 0.034), mammographic parenchymal density (p = 0.008). and ≥ 3 separate ADH foci found on biopsy (p = 0.024). Mammographic parenchymal density (hazard ratio [HR], 0.04; 95% confidence interval [CI], 0.005–0.35; p = 0.014), presence of a mass on ultrasound (HR, 10.50; 95% CI, 9.21–25.2; p = 0.010), and number of ADH foci (HR, 1.877; 95% CI, 1.831–1.920; p = 0.002) remained significant in multivariate analysis and were included in the nomogram.

Conclusion

Our model provided good discrimination of breast cancer risk prediction (C-statistic of 0.81; 95% CI, 0.74–0.88) and selected for a subset of women at low risk (2.1%) of malignant upgrade, who may avoid surgical excision following a CNB diagnosis of ADH.

Value of multimodality imaging in the diagnosis of breast lesions with calcification: A retrospective study

PURPOSE

To assess the value of conventional ultrasound (US), contrast-enhanced ultrasound (CEUS) and mammography in the diagnosis of breast lesions with calcifications.

METHODS

A total of 87 breast lesions with calcification were subjected to US, CEUS and mammography and divided into 3 groups: Group A (all cases), Group A1 (31 cases who underwent US and CEUS first followed by mammography), and Group A2 (56 cases who underwent mammography first followed by US and CEUS). A receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of different methods in different groups.

RESULTS

In Group A, the area under the ROC curve (AUROC) of CEUS were 0.937, which were significantly higher than that of mammography (p < 0.05). In Group A1, the AUROC of CEUS were 0.842, which were not significantly different from that of US and mammography (p > 0.05). In Group A2, the AUROC of CEUS were 0.987, which were significantly higher than that of mammography and US (p < 0.05).

CONCLUSION

Based on the mammography results, the combination of US and CEUS might improve the diagnostic efficacy in breast lesions with calcification.

Race May Not Impact Endocrine Therapy-Related Changes in Breast Density

BACKGROUND

Reduction in breast density may be a biomarker of endocrine therapy (ET) efficacy. Our objective was to assess the impact of race on ET-related changes in volumetric breast density (VBD).

METHODS

This retrospective cohort study assessed longitudinal changes in VBD measures in women with estrogen receptor-positive invasive breast cancer treated with ET. VBD, the ratio of fibroglandular volume (FGV) to breast volume (BV), was measured using Volpara software. Changes in measurements were evaluated using a multivariable linear mixed effects model.

RESULTS

Compared with white women (n = 191), black women (n = 107) had higher rates of obesity [mean ± SD body mass index (BMI) 34.5 ± 9.1 kg/m² vs. 30.6 ± 7.0 kg/m², P < 0.001] and premenopausal status (32.7% vs. 16.7%, P = 0.002). Age- and BMI-adjusted baseline FGV, BV, and VBD were similar between groups. Modeled longitudinal changes were also similar: During a follow-up of 30.7 ± 15.0 months (mean ± SD), FGV decreased over time in premenopausal women (slope = -0.323 cm³; SE = 0.093; P = 0.001), BV increased overall (slope = 2.475 cm³; SE = 0.483; P < 0.0001), and VBD decreased (premenopausal slope = -0.063%, SE = 0.011; postmenopausal slope = -0.016%, SE = 0.004; P < 0.0001). Race was not significantly associated with these longitudinal changes, nor did race modify the effect of time on these changes. Higher BMI was associated with lower baseline VBD (P < 0.0001). Among premenopausal women, VBD declined more steeply for women with lower BMI (time × BMI, P = 0.0098).

CONCLUSIONS

Race does not appear to impact ET-related longitudinal changes in VBD.

IMPACT

Racial disparities in estrogen receptor-positive breast cancer recurrence and mortality may not be explained by differential declines in breast density due to ET.

Postoperative Cancer Surveillance Following Oncoplastic Surgery with Latissimus Dorsi Flap: a Matched Case-Control Study

BACKGROUND

The latissimus dorsi (LD) myocutaneous flap is a widely used local option in oncoplastic surgery for avoiding breast deformities; however, concerns exist regarding its influence in monitoring recurrence. In this study, we evaluated the impact of this flap on postoperative cancer surveillance.

METHODS

Each patient receiving oncoplastic surgery with LD flap after partial mastectomy were matched in age, cancer stage, and body mass index with patients receiving partial mastectomy alone. Twenty-nine patients with the oncoplastic LD flap received 99 mammograms and 139 ultrasonograms, while 29 patients with partial mastectomy alone underwent 92 mammograms and 129 ultrasonograms. Mammographic and ultrasonographic findings were classified by Breast Imaging Reporting and Data System (BI-RADS) category and reviewed. Any recommendations for additional evaluation and recurrence were documented.

RESULTS

During an average follow-up period of 44 months, although the oncoplastic group demonstrated more newly developed benign calcifications (control 14% vs. oncoplastic 41%; p = 0.019) on mammography, the percentage of recall for additional imaging in category 0, and the short-interval follow-up in category 3, was not different between the control and oncoplastic group. Regarding ultrasonography, BI-RADS category was also not different between the two groups; however, the control group showed more fluid collections than the oncoplastic group (control 21% vs. oncoplastic 0%; p = 0.023). One case of local recurrence was observed in the control group.

CONCLUSION

Although there was an increase in benign calcifications in the oncoplastic group, there were no additional abnormal findings requiring further intervention. We concluded that the LD flap for oncoplastic surgery does not interfere with cancer surveillance, and even decreases the rate of fluid collection.

Does Breast Density Increase the Risk of Re-excision for Women with Breast Cancer Having Breast-Conservation Therapy?

BACKGROUND

Women with dense breasts may have less-accurate preoperative evaluation of extent of disease, potentially affecting the achievement of negative margins. The goal of this study is to examine the association between breast density and re-excision rates in women having breast-conserving surgery for invasive breast cancer.

PATIENTS AND METHODS

Women with stage I/II invasive breast cancer treated with breast-conserving surgery between 1/1/2014 and 10/31/2014 were included. Breast density was assessed by two radiologists. The association between breast density and re-excision was examined using logistic regression.

RESULTS

Seven hundred and one women were included. Overall, 106 (15.1%) women had at least one re-excision. Younger age at diagnosis was associated with increased breast density (p < 0.001). On univariable analysis, increased breast density was associated with significantly increased odds of re-excision (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.04-1.83), as was multifocal disease, human epidermal growth factor receptor 2 (HER2) positive status, and extensive intraductal component (EIC) (all p < 0.05). On multivariable analysis, breast density remained significantly associated with increased odds of re-excision (OR 1.37, 95% CI 1.00-1.86), as did multifocality and EIC. HER2 positive status was not significantly associated with re-excision on multivariable analysis.

CONCLUSIONS

Women with dense breasts are more likely to need additional surgery (re-excision after breast-conserving surgery), but increased breast density did not adversely affect disease-free survival in our study. Our findings support the need for further study in developing techniques that can help decrease re-excisions for women with dense breasts who undergo breast-conserving surgery.

Preliminary investigation of mammographic density among women in Riyadh: association with breast cancer risk factors and implications for screening practices

PURPOSE

Improved mammographic sensitivity is associated with reduced mammographic density. This study aims to: provide a preliminary report on mammographic density among women in Riyadh; identify risk factors associated with mammographic density; and consider the potential implications for screening practices.

METHODS

Based on a cross-sectional design, we examined a total of 792 women using an area-based mammographic density method (LIBRA). Spearman's correlation, Mann-Whitney U, Kruskal-Wallis and binary logistic regression were used for analyses.

RESULTS

The study population had a mean age of 49.6 years and a high proportion of participants were overweight or obese (90%). A large number of women had low mammographic density, with a mean dense breast area of 19.1 cm² and percent density of 10.3 cm². Slightly more than half of the variations in the dense breast area and percent density models were explained by BMI. In the adjusted analyses, BMI, menopausal status, age at menarche and number of children remained statistically significant predictors.

CONCLUSION

Given the high proportion of women with low mammographic density, our findings suggest that women living in Riyadh may not require additional imaging strategies beyond mammography to detect breast cancers. The high proportion of obese women reported here and across Saudi Arabia suggests that mammographic density is less likely to have an adverse impact on mammographic sensitivity. Thus and to improve clinical outcomes among Saudi women, annual mammography and commencing screening at a younger age are suggested. Additional studies are required to shed further light on our findings.

Serum insulin-like growth factor (IGF)-I and IGF binding protein-3 in relation to terminal duct lobular unit involution of the normal breast in Caucasian and African American women: The Susan G. Komen Tissue Bank

Lesser degrees of terminal duct lobular unit (TDLU) involution, as reflected by higher numbers of TDLUs and acini/TDLU, are associated with elevated breast cancer risk. In rodent models, the insulin-like growth factor (IGF) system regulates involution of the mammary gland. We examined associations of circulating IGF measures with TDLU involution in normal breast tissues among women without precancerous lesions. Among 715 Caucasian and 283 African American (AA) women who donated normal breast tissue samples to the Komen Tissue Bank between 2009 and 2012 (75% premenopausal), serum concentrations of IGF-I and binding protein (IGFBP)-3 were quantified using enzyme-linked immunosorbent assay. Hematoxilyn and eosin-stained tissue sections were assessed for numbers of TDLUs ("TDLU count"). Zero-inflated Poisson regression models with a robust variance estimator were used to estimate relative risks (RRs) for association of IGF measures (tertiles) with TDLU count by race and menopausal status, adjusting for potential confounders. AA (vs. Caucasian) women had higher age-adjusted mean levels of serum IGF-I (137 vs. 131 ng/mL, p = 0.07) and lower levels of IGFBP-3 (4165 vs. 4684 ng/mL, p < 0.0001). Postmenopausal IGFBP-3 was inversely associated with TDLU count among AA (RR_T3vs.T1  = 0.49, 95% CI = 0.28-0.84, p-trend = 0.04) and Caucasian (RR_T3vs.T1 =0.64, 95% CI = 0.42-0.98, p-trend = 0.04) women. In premenopausal women, higher IGF-I:IGFBP-3 ratios were associated with higher TDLU count in Caucasian (RR_T3vs.T1 =1.33, 95% CI = 1.02-1.75, p-trend = 0.04), but not in AA (RR_T3vs.T1 =0.65, 95% CI = 0.42-1.00, p-trend = 0.05), women. Our data suggest a role of the IGF system, particularly IGFBP-3, in TDLU involution of the normal breast, a breast cancer risk factor, among Caucasian and AA women.

Mammographic breast density in recent and longer-standing ethiopian immigrants to israel

High breast density is associated with an increased risk of breast cancer development. Little is known concerning ethnic variations in breast density and its relevant contributing factors. We aimed to study breast density among Ethiopian immigrants to Israel in comparison with Israeli-born women and to determine any effect on breast density of the length of residency in the immigrant population. Mammographic breast density using the BI-RADS system was estimated and compared between 77 women of Ethiopian origin who live in Israel and 177 Israeli-born controls. Logistic regression analysis was performed to estimate the odds ratios (OR) for high density (BI-RADS score ≥ 3) vs low density (BI-RADS score < 3) cases, comparing the 2 origin groups. Ethiopian-born women had a crude OR of 0.15 (95% CI: 0.08-0.26) for high breast density compared with Israeli-born women. Adjustments for various cofounders did not affect the results. Time since immigration to Israel seemed to modify the relationship, with a stronger association for women who immigrated within 2 years prior to mammography (OR:0.07, 95% CI: 0.03-0.17) as opposed to women with a longer residency stay in Israel (OR:0.23, 95% CI:0.10-0.50). Adjustments of various confounders did not alter these findings. Breast density in Ethiopian immigrants to Israel is significantly lower than that of Israeli-born controls. Our study suggests a positive association between time since immigration and breast density. Future studies are required to define the possible effects of dietary change on mammographic density following immigration.

Exploration of Racial Differences in Reproductive Factors for Breast Cancer among Women aged 55-74

Background Reproductive factors have been well-documented risk factors for breast cancer. Few studies have examined whether the associations between reproductive factors and breast cancer differed across races/ethnicities. Methods We analyzed a sub-sample (70, 734) of the Prostate, Lung, Colorectal, and Ovarian (PLCO) dataset. Participants with valid baseline questionnaire and without breast cancer at enrollment were included into analysis. We stratified the participants into subgroups based on their races/ethnicities then estimated the effects of the reproductive factors on breast cancer within each group using Cox-proportion regression models. Results Oral contraceptive use (HR=1.09, 95% confidence interval or CI=1.01, 1.18), advanced age at natural menopause (HR=1.25, 95% CI=1.06, 1.49) were associated with increased risk of breast cancer in non-Hispanic Caucasians group only. Long term use of menopausal hormone therapy (more than five years) was associated with increased risk of breast cancer in both of the non-Hispanic Caucasian (HR=1.44, 95% CI=1.31, 1.59) group and the non-Hispanic Asian/Pacific Islander (HR=1.98, 95% CI=1.23, 3.20) group, but not in other race/ethnic groups. Hispanics who tried to become pregnant for a year or more had increased risk of breast cancer (HR=2.60, 95% CI=1.05, 6.46) than their counterparts without difficulty in getting pregnancy. In addition, surgery induced menopause was found to be a protective factor for breast cancer in non-Hispanic Caucasian (HR=0.88, 95% CI=0.79, 0.98) group only.

Conclusions We concluded that different races/ethnicities had different breast cancer related reproductive risk factors. Non-Hispanic Caucasians had the most breast cancer related reproductive risk factors, while the minorities had none or few breast cancer related reproductive risk factors and among these few factors only 1 was also risk factor for non-Hispanic Caucasians.

Migration History, Language Acculturation, and Mammographic Breast Density

Background: Breast cancer incidence is lower in many U.S. ethnic minority and foreign-born population groups. Investigating whether migration and acculturation patterns in risk are reflected in disease biomarkers may help to elucidate the underlying mechanisms.Methods: We compared the distribution of breast cancer risk factors across U.S.-born white, African American and Hispanic women, and foreign-born Hispanic women (n = 477, ages 40-64 years, 287 born in Caribbean countries). We used linear regression models to examine the associations of migration history and linguistic acculturation with mammographic breast density (MBD), measured using computer-assisted methods as percent and area of dense breast tissue.Results: The distribution of most breast cancer risk factors varied by ethnicity, nativity, and age at migration. In age- and body mass index-adjusted models, U.S.-born women did not differ in average MBD according to ethnicity, but foreign-born Hispanic women had lower MBD [e.g., -4.50%; 95% confidence interval (CI), -7.12 to -1.89 lower percent density in foreign- vs. U.S.-born Hispanic women]. Lower linguistic acculturation and lower percent of life spent in the United States were also associated with lower MBD [e.g., monolingual Spanish and bilingual vs. monolingual English speakers, respectively, had 5.09% (95% CI, -8.33 to -1.85) and 3.34% (95% CI, -6.57 to -0.12) lower percent density]. Adjusting for risk factors (e.g., childhood body size, parity) attenuated some of these associations.Conclusions: Hispanic women predominantly born in Caribbean countries have lower MBD than U.S.-born women of diverse ethnic backgrounds, including U.S.-born Hispanic women of Caribbean heritage.Impact: MBD may provide insight into mechanisms driving geographic and migration variations in breast cancer risk. Cancer Epidemiol Biomarkers Prev; 27(5); 566-74. ©2018 AACR.

Mammographic Breast Density and Breast Cancer Molecular Subtypes: The Kenyan-African Aspect

Introduction

Data examining mammographic breast density (MBD) among patients in Sub-Saharan Africa are sparse. We evaluated how MBD relates to breast cancer characteristics in Kenyan women undergoing diagnostic mammography.

Methods

This cross-sectional study included women with pathologically confirmed breast cancers (n = 123). Pretreatment mammograms of the unaffected breast were assessed to estimate absolute dense area (cm²), nondense area (cm²), and percent density (PD). Relationships between density measurements and clinical characteristics were evaluated using analysis of covariance.

Results

Median PD and dense area were 24.9% and 85.3 cm². Higher PD and dense area were observed in younger women (P < 0.01). Higher dense and nondense areas were observed in obese women (P-trend < 0.01). Estrogen receptor (ER) positive patients (73%) had higher PD and dense area than ER-negative patients (P ≤ 0.02). Triple negative breast cancer (TNBC) patients (17%) had lower PD and dense area (P ≤ 0.01) compared with non-TNBCs. No associations were observed between MBD and tumor size and grade.

Conclusions

Our findings show discordant relationships between MBD and molecular tumor subtypes to those previously observed in Western populations. The relatively low breast density observed at diagnosis may have important implications for cancer prevention initiatives in Kenya. Subsequent larger studies are needed to confirm these findings.

Breast Density and Risk of Breast Cancer in Asian Women: A Meta-analysis of Observational Studies

OBJECTIVES

The established theory that breast density is an independent predictor of breast cancer risk is based on studies targeting white women in the West. More Asian women than Western women have dense breasts, but the incidence of breast cancer is lower among Asian women. This meta-analysis investigated the association between breast density in mammography and breast cancer risk in Asian women.

METHODS

PubMed and Scopus were searched, and the final date of publication was set as December 31, 2015. The effect size in each article was calculated using the interval-collapse method. Summary effect sizes (sESs) and 95% confidence intervals (CIs) were calculated by conducting a meta-analysis applying a random effect model. To investigate the dose-response relationship, random effect dose-response meta-regression (RE-DRMR) was conducted.

RESULTS

Six analytical epidemiology studies in total were selected, including one cohort study and five case-control studies. A total of 17 datasets were constructed by type of breast density index and menopausal status. In analyzing the subgroups of premenopausal vs. postmenopausal women, the percent density (PD) index was confirmed to be associated with a significantly elevated risk for breast cancer (sES, 2.21; 95% CI, 1.52 to 3.21; I²=50.0%). The RE-DRMR results showed that the risk of breast cancer increased 1.73 times for each 25% increase in PD in postmenopausal women (95% CI, 1.20 to 2.47).

CONCLUSIONS

In Asian women, breast cancer risk increased with breast density measured using the PD index, regardless of menopausal status. We propose the further development of a breast cancer risk prediction model based on the application of PD in Asian women.

Racial Differences in Quantitative Measures of Area and Volumetric Breast Density

BACKGROUND

Increased breast density is a strong risk factor for breast cancer and also decreases the sensitivity of mammographic screening. The purpose of our study was to compare breast density for black and white women using quantitative measures.

METHODS

Breast density was assessed among 5282 black and 4216 white women screened using digital mammography. Breast Imaging-Reporting and Data System (BI-RADS) density was obtained from radiologists' reports. Quantitative measures for dense area, area percent density (PD), dense volume, and volume percent density were estimated using validated, automated software. Breast density was categorized as dense or nondense based on BI-RADS categories or based on values above and below the median for quantitative measures. Logistic regression was used to estimate the odds of having dense breasts by race, adjusted for age, body mass index (BMI), age at menarche, menopause status, family history of breast or ovarian cancer, parity and age at first birth, and current hormone replacement therapy (HRT) use. All statistical tests were two-sided.

RESULTS

There was a statistically significant interaction of race and BMI on breast density. After accounting for age, BMI, and breast cancer risk factors, black women had statistically significantly greater odds of high breast density across all quantitative measures (eg, PD nonobese odds ratio [OR] = 1.18, 95% confidence interval [CI] = 1.02 to 1.37, P = .03, PD obese OR = 1.26, 95% CI = 1.04 to 1.53, P = .02). There was no statistically significant difference in BI-RADS density by race.

CONCLUSIONS

After accounting for age, BMI, and other risk factors, black women had higher breast density than white women across all quantitative measures previously associated with breast cancer risk. These results may have implications for risk assessment and screening.

Improvement in risk prediction, early detection and prevention of breast cancer in the NHS Breast Screening Programme and family history clinics: a dual cohort study

Background

In the UK, women are invited for 3-yearly mammography screening, through the NHS Breast Screening Programme (NHSBSP), from the ages of 47–50 years to the ages of 69–73 years. Women with family histories of breast cancer can, from the age of 40 years, obtain enhanced surveillance and, in exceptionally high-risk cases, magnetic resonance imaging. However, no NHSBSP risk assessment is undertaken. Risk prediction models are able to categorise women by risk using known risk factors, although accurate individual risk prediction remains elusive. The identification of mammographic breast density (MD) and common genetic risk variants [single nucleotide polymorphisms (SNPs)] has presaged the improved precision of risk models.

Objectives

To (1) identify the best performing model to assess breast cancer risk in family history clinic (FHC) and population settings; (2) use information from MD/SNPs to improve risk prediction; (3) assess the acceptability and feasibility of offering risk assessment in the NHSBSP; and (4) identify the incremental costs and benefits of risk stratified screening in a preliminary cost-effectiveness analysis.

Design

Two cohort studies assessing breast cancer incidence.

Setting

High-risk FHC and the NHSBSP Greater Manchester, UK.

Participants

A total of 10,000 women aged 20–79 years [Family History Risk Study (FH-Risk); UK Clinical Research Network identification number (UKCRN-ID) 8611] and 53,000 women from the NHSBSP [aged 46–73 years; Predicting the Risk of Cancer At Screening (PROCAS) study; UKCRN-ID 8080].

Interventions

Questionnaires collected standard risk information, and mammograms were assessed for breast density by a number of techniques. All FH-Risk and 10,000 PROCAS participants participated in deoxyribonucleic acid (DNA) studies. The risk prediction models Manual method, Tyrer–Cuzick (TC), BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm) and Gail were used to assess risk, with modelling based on MD and SNPs. A preliminary model-based cost-effectiveness analysis of risk stratified screening was conducted.

Main outcome measures

Breast cancer incidence.

Data sources

The NHSBSP; cancer registration.

Results

A total of 446 women developed incident breast cancers in FH-Risk in 97,958 years of follow-up. All risk models accurately stratified women into risk categories. TC had better risk precision than Gail, and BOADICEA accurately predicted risk in the 6268 single probands. The Manual model was also accurate in the whole cohort. In PROCAS, TC had better risk precision than Gail [area under the curve (AUC) 0.58 vs. 0.54], identifying 547 prospective breast cancers. The addition of SNPs in the FH-Risk case–control study improved risk precision but was not useful inBRCA1(breast cancer 1 gene) families. Risk modelling of SNPs in PROCAS showed an incremental improvement from using SNP18 used in PROCAS to SNP67. MD measured by visual assessment score provided better risk stratification than automatic measures, despite wide intra- and inter-reader variability. Using a MD-adjusted TC model in PROCAS improved risk stratification (AUC = 0.6) and identified significantly higher rates (4.7 per 10,000 vs. 1.3 per 10,000;p < 0.001) of high-stage cancers in women with above-average breast cancer risks. It is not possible to provide estimates of the incremental costs and benefits of risk stratified screening because of lack of data inputs for key parameters in the model-based cost-effectiveness analysis.

Conclusions

Risk precision can be improved by using DNA and MD, and can potentially be used to stratify NHSBSP screening. It may also identify those at greater risk of high-stage cancers for enhanced screening. The cost-effectiveness of risk stratified screening is currently associated with extensive uncertainty. Additional research is needed to identify data needed for key inputs into model-based cost-effectiveness analyses to identify the impact on health-care resource use and patient benefits.

Future work

A pilot of real-time NHSBSP risk prediction to identify women for chemoprevention and enhanced screening is required.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme. The DNA saliva collection for SNP analysis for PROCAS was funded by the Genesis Breast Cancer Prevention Appeal.

Contrast-enhanced ultrasound improved performance of breast imaging reporting and data system evaluation of critical breast lesions

AIM: To determine whether contrast-enhanced ultrasound (CEUS) can improve the precision of breast imaging reporting and data system (BI-RADS) categorization.

METHODS: A total of 230 patients with 235 solid breast lesions classified as BI-RADS 4 on conventional ultrasound were evaluated. CEUS was performed within one week before core needle biopsy or surgical resection and a revised BI-RADS classification was assigned based on 10 CEUS imaging characteristics. Receiver operating characteristic curve analysis was then conducted to evaluate the diagnostic performance of CEUS-based BI-RADS assignment with pathological examination as reference criteria.

RESULTS: The CEUS-based BI-RADS evaluation classified 116/235 (49.36%) lesions into category 3, 20 (8.51%), 13 (5.53%) and 12 (5.11%) lesions into categories 4A, 4B and 4C, respectively, and 74 (31.49%) into category 5. Selecting CEUS-based BI-RADS category 4A as an appropriate cut-off gave sensitivity and specificity values of 85.4% and 87.8%, respectively, for the diagnosis of malignant disease. The cancer-to-biopsy yield was 73.11% with CEUS-based BI-RADS 4A selected as the biopsy threshold compared with 40.85% otherwise, while the biopsy rate was only 42.13% compared with 100% otherwise. Overall, only 4.68% of invasive cancers were misdiagnosed.

CONCLUSION: This pilot study suggests that evaluation of BI-RADS 4 breast lesions with CEUS results in reduced biopsy rates and increased cancer-to-biopsy yields.

Supplemental Screening for Breast Cancer in Women With Dense Breasts: A Systematic Review for the U.S. Preventive Services Task Force

BACKGROUND

Screening mammography has lower sensitivity and specificity in women with dense breasts, who experience higher breast cancer risk.

PURPOSE

To perform a systematic review of reproducibility of Breast Imaging Reporting and Data System (BI-RADS) density categorization and test performance and clinical outcomes of supplemental screening with breast ultrasonography, magnetic resonance imaging (MRI), and digital breast tomosynthesis (DBT) in women with dense breasts and negative mammography results.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and Cochrane database from January 2000 to July 2015.

STUDY SELECTION

Studies reporting BI-RADS density reproducibility or supplemental screening results for women with dense breasts.

DATA EXTRACTION

Quality assessment and abstraction of 24 studies from 7 countries; 6 studies were good-quality.

DATA SYNTHESIS

Three good-quality studies reported reproducibility of BI-RADS density; 13% to 19% of women were recategorized between "dense" and "nondense" at subsequent screening. Two good-quality studies reported that sensitivity of ultrasonography for women with negative mammography results ranged from 80% to 83%; specificity, from 86% to 94%; and positive predictive value (PPV), from 3% to 8%. The sensitivity of MRI ranged from 75% to 100%; specificity, from 78% to 94%; and PPV, from 3% to 33% (3 studies). Rates of additional cancer detection with ultrasonography were 4.4 per 1000 examinations (89% to 93% invasive); recall rates were 14%. Use of MRI detected 3.5 to 28.6 additional cancer cases per 1000 examinations (34% to 86% invasive); recall rates were 12% to 24%. Rates of cancer detection with DBT increased by 1.4 to 2.5 per 1000 examinations compared with mammography alone (3 studies). Recall rates ranged from 7% to 11%, compared with 7% to 17% with mammography alone. No studies examined breast cancer outcomes.

LIMITATIONS

Good-quality evidence was sparse. Studies were small and CIs were wide. Definitions of recall were absent or inconsistent.

CONCLUSION

Density ratings may be recategorized on serial screening mammography. Supplemental screening of women with dense breasts finds additional breast cancer but increases false-positive results. Use of DBT may reduce recall rates. Effects of supplemental screening on breast cancer outcomes remain unclear.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Breast cancer diagnosis from screening in trinidad and tobago: opportunities for cancer prevention

Trinidad and Tobago (TT) experiences the highest breast cancer mortality in the Caribbean; the distribution of traditional breast cancer risk factors in this population has not been analyzed. Data on women who underwent breast cancer screening at the TT Cancer Society between January 2009-December 2011(N = 2,689) were retrospectively collected. The screening detected 131 incident breast cancers; variables significantly associated with breast cancer diagnosis were, a positive family history of breast cancer (adjusted odds ratio [ORadj]: 1.55; 95% CI 1.00-2.41), presence of symptoms (ORadj: 1.91; 95% CI 1.25-2.92), and previous breast surgery (ORadj: 1.67; 95% CI 0.97-2.88). Breast cancer was significantly associated with increased breast density. Among healthy women, breast density was positively associated with nulliparity (ORadj: 1.46, 1.37, 2.52 respectively for density level 2, 3 and 4 vs. 1) and previous breast surgeries (ORadj: 2.27, 3.09 and 4.13 respectively for density level 2, 3 and 4 vs. 1). This analysis confirms that breast density is an important predictor of newly diagnosed breast cancer in this Caribbean population. Screening is still a diagnostic tool rather than a preventive measure in TT.

Type 2 diabetes and mammographic breast density among underserved women

PURPOSE

We conducted a study of women recruited at Meharry Medical College, a historically black medical school, to investigate the relationship between diabetes and mammographic breast density.

METHODS

A total of 476 women completed in-person interviews, body measurements, and full-field digital mammograms on a Hologic mammography unit from December 2011 to February 2014. Average percent breast density for the left and right breasts combined was estimated using Quantra, an automated algorithm for volumetric assessment of breast tissue. The prevalence of type 2 diabetes was determined by self-report.

RESULTS

After adjustment for confounding variables, the mean percent breast density among premenopausal women with type 2 diabetes [[Formula: see text] 13.8 %, 95 % confidence interval (CI) 11.6-15.9] was nonsignificantly lower than that of women without type 2 diabetes ([Formula: see text] 15.9 %, 95 % CI 15.0-16.8) (p = 0.07); however, there was no association among postmenopausal women. The effect of type 2 diabetes in severely obese women (BMI ≥ 35) appeared to differ by menopausal status with a reduction in mean percent breast density in premenopausal women, but an increase in mean percent breast density in postmenopausal women which could have been due to chance.

CONCLUSIONS

Confirmation of our findings in larger studies may assist in clarifying the role of the insulin signaling breast cancer pathway in women with high breast density.

Breast contrast-enhanced ultrasound: is a scoring system feasible? A preliminary study in China

OBJECTIVES

Although many studies about breast contrast-enhanced ultrasound had been conducted, clear diagnostic criteria for evaluating enhancement patterns are still lacking. This study aims to identify significant indicators for breast contrast-enhanced ultrasound and to establish an initial scoring system.

MATERIALS AND METHODS

Totally 839 patients were included in the study. This study was divided into two parts. 364 patients were included in part 1 while 475 in part 2. Conventional ultrasound and contrast-enhanced ultrasound were used to examine each lesion. Only the cases in part 2 were also examined by elastography. In part 1, Logistic regression analysis was performed to predict significant variables. A 5-point scoring system was developed based on the results. In part 2, the scoring system was used to evaluate all the breast lesions. To evaluate the diagnostic efficacy of the new scoring system, it was compared with the system established for elastography and conventional ultrasound (BI-RADS).

RESULTS

Three independent variables, namely, lesion scope, margin, and shape were selected in the final step of the logistic regression analysis in part 1. In part 2, the area under the ROC (receiver operating characteristic) curve for the contrast-enhanced scoring system was 0.912. The difference in the diagnostic capabilities of the contrast-enhanced scoring system and elastography was not statistically significant (P = 0.17). The difference in the diagnostic capabilities of the contrast-enhanced scoring system and BI-RADS was statistically significant (P<0.001).

CONCLUSIONS

The contrast-enhanced patterns of benign and malignant breast tumors are different. The application of a 5-point scoring system for contrast-enhanced ultrasound is clinically promising.

Distribution of mammographic density and its influential factors among Chinese women

BACKGROUND

Mammographic density (MD) has not been systematically investigated among Chinese women. Breast cancer screening programmes provided detailed information on MD in a large number of asymptomatic women.

METHODS

In the Multi-modality Independent Screening Trial (MIST), we estimated the association between MD and its influential factors using logistic regression, adjusting for age, body mass index (BMI) and study area. Differences between Chinese and other ethnic groups with respect to MD were also explored with adjustment for age and BMI.

RESULTS

A total of 28 388 women aged 45 to 65 years, who had been screened by mammography, were enrolled in the study. Of these, 49.2% were categorized as having dense breasts (BI-RADS density 3 and 4) and 50.8% as fatty breasts (BI-RADS density 1 and 2). Postmenopausal status [odds ratio (OR) = 0.66; 95% confidence interval (CI): 0.62-0.70] and higher number of live births (OR = 0.56; 95% CI: 0.46-0.68) were inversely associated with MD, whereas prior benign breast disease (OR = 1.48; 95% CI: 1.40-1.56) and later age at first birth (OR = 1.17; 95% CI: 1.08-1.27) were positively associated with MD. In comparison with the data from the Breast Cancer Surveillance Consortium, we found that women in MIST were more likely to have fatty breasts than Americans (from the Breast Cancer Surveillance Consortium) in the older age group (≥50 years) but more likely to have dense breasts in the younger age group (<50 years).

CONCLUSIONS

This study suggests that several risk factors for breast cancer were associated with breast density in Chinese women. Information on the determinants of mammographic density may provide valuable insights into breast cancer aetiology.

Mammographic density and breast cancer risk in White and African American Women

Mammographic density is a strong risk factor for breast cancer, but limited data are available in African American (AA) women. We examined the association between mammographic density and breast cancer risk in AA and white women. Cases (n = 491) and controls (n = 528) were from the Carolina Breast Cancer Study (CBCS) who also had mammograms recorded in the Carolina Mammography Registry (CMR). Mammographic density was reported to CMR using Breast Imaging Reporting and Data System (BI-RADS) categories. Increasing mammographic density was associated with increased breast cancer risk among all women. After adjusting for potential confounders, a monotonically increasing risk of breast cancer was observed between the highest versus the lowest BI-RADS density categories [OR = 2.45, (95 % confidence interval: 0.99, 6.09)]. The association was stronger in whites, with ~40 % higher risk among those with extremely dense breasts compared to those with scattered fibroglandular densities [1.39, (0.75, 2.55)]. In AA women, the same comparison suggested lower risk [0.75, (0.30, 1.91)]. Because age, obesity, and exogenous hormones have strong associations with breast cancer risk, mammographic density, and race in the CBCS, effect measure modification by these factors was considered. Consistent with previous literature, density-associated risk was greatest among those with BMI > 30 and current hormone users (P value = 0.02 and 0.01, respectively). In the CBCS, mammographic density is associated with increased breast cancer risk, with some suggestion of effect measure modification by race, although results were not statistically significant. However, exposures such as BMI and hormone therapy may be important modifiers of this association and merit further investigation.

Breast density, body mass index, and risk of tumor marker-defined subtypes of breast cancer

PURPOSE

Breast density and body mass index (BMI) are correlated attributes and are both potentially modifiable risk factors for breast cancer. However, relationships between these factors and risk of molecularly-defined subtypes of breast cancer have not been established.

METHODS

We used breast density and BMI data collected by the Breast Cancer Surveillance Consortium from 1,054,466 women ages 40 to 84 years receiving mammography, including 13,797 women subsequently diagnosed with breast cancer. Cases were classified into three groups on the basis of expression of the estrogen receptor (ER), progesterone receptor (PR), and HER2:1) ER-positive (ER+, n = 10,026), 2) HER2-expressing (ER-negative/PR-negative/HER2-positive, n = 308), or triple-negative (ER-negative/PR-negative/HER2-negative, n = 705). Using Cox regression, we evaluated subtype-specific associations with breast density and BMI.

RESULTS

Breast density was similarly positively associated with risk of all subtypes, especially among women ages 40 to 64 years. BMI was positively associated with risks of ER+ and triple-negative breast cancer in women ages 50 to 84 who were not users of hormone therapy.

CONCLUSIONS

Breast density is positively associated with breast cancer risk, regardless of disease subtype. Associations with BMI appear to vary more by breast cancer subtype. Additional studies are needed to confirm and further characterize risk factors for HER2-expressing and triple-negative breast cancer.

Reproductive and menstrual factors and mammographic density in African American, Caribbean, and white women

OBJECTIVE

We investigated the associations between reproductive and menstrual risk factors for breast cancer and mammographic density, a strong risk factor for breast cancer, in a predominantly ethnic minority and immigrant sample.

METHODS

We interviewed women (42% African American, 22% African Caribbean, 22% White, 9% Hispanic Caribbean, 5% other) without a history of breast cancer during their mammography appointment (n = 191, mean age = 50). We used a computer-assisted method to measure the area and percentage of dense breast tissue from cranio-caudal mammograms. We used multivariable linear regression analyses to estimate the associations between reproductive and menstrual risk factors and mammographic density.

RESULTS

Age was inversely associated with percent density and dense area, and body mass index (BMI) was inversely associated with percent density. Adjusting for age, BMI, ethnicity and menopausal status, later age at menarche (e.g., β = -7.37, 95% CI: -12.29, -2.46 for age ≥ 13 years vs. ≤ 11 years), and any use of hormonal birth control (HBC) methods (β = -5.10, 95% CI: -9.37, -0.84) were associated with reduced dense area. Ethnicity and nativity (foreign- vs. US-born) were not directly associated with density despite variations in the distribution of several risk factors across ethnic and nativity groups.

CONCLUSIONS

The mean level of mammographic density did not differ across ethnic and nativity groups, but several risk factors for breast cancer were associated with density in ethnic minority and immigrant women.

Breast and prostate cancer survival in Michigan: can geographic analyses assist in understanding racial disparities?

BACKGROUND

Racial disparities in survival from breast and prostate cancer are well established; however, the roles of societal/socioeconomic factors and innate/genetic factors in explaining the disparities remain unclear. One approach for evaluating the relative importance of societal and innate factors is to quantify how the magnitude of racial disparities changes according to the geographic scales at which data are aggregated. Disappearance of racial disparities for some levels of aggregation would suggest that modifiable factors not inherent at the individual level are responsible for the disparities.

METHODS

The Michigan Cancer Surveillance Program compiled a dataset from 1985 to 2002 that included 124,218 breast cancer cases and 120,615 prostate cancer cases with 5-year survival rates of 78% and 75%, respectively. Absolute and relative differences in survival rates for whites and blacks were quantified across different geographic scales using statistics that adjusted for population size to account for the small numbers problem common with minority populations.

RESULTS

Whites experienced significantly higher survival rates for prostate and breast cancer compared with blacks throughout much of southern Michigan in analyses conducted using federal House legislative districts; however, in smaller geographic units (state House legislative districts and community-defined neighborhoods), disparities diminished and virtually disappeared.

CONCLUSIONS

The current results suggest that modifiable societal factors are responsible for apparent racial disparities in breast and prostate cancer survival observed at larger geographic scales. This research presents a novel strategy for taking advantage of inconsistencies across geographic scales to evaluate the relative importance of innate and societal-level factors in explaining racial disparities in cancer survival.

Ethnic variations in mammographic density: a British multiethnic longitudinal study

It is not known whether the 20-30% lower breast cancer incidence rates in first-generation South Asian and Afro-Caribbean women relative to Caucasian women in the United Kingdom are reflected in mammographic density. The authors conducted a United Kingdom population-based multiethnic study of mammographic density at ages 50-64 years in 645 women. Data on breast cancer risk factors were obtained using a questionnaire/telephone interview. Threshold percent density was assessed on 5,277 digitized mammograms taken in 1995-2004 and was analyzed using multilevel models. Both ethnic minorities were characterized by more protective breast cancer risk factor distributions than Caucasians, such as later menarche, shorter stature, higher parity, earlier age at first birth, and less use of hormone therapy, but they had a higher mean body mass index; the last four factors were associated with lower mammographic density. Age-adjusted percent mammographic densities in Afro-Caribbeans and South Asians were 5.6% (95% confidence interval (CI): 3.5, 7.5) and 5.9% (95% CI: 3.6, 8.0) lower, respectively, than in Caucasians. Lower densities were partly attributed to higher body mass index, less use of hormone therapy, and a protective reproductive history, but these factors did not account entirely for ethnic differences, since fully adjusted mean densities were 1.3% (95% CI: -1.3, 3.7) and 3.8% (95% CI: 1.1, 6.3) lower, respectively. Ethnic differences in mammographic density are consistent with those for breast cancer risk.

Disparities in breast cancer incidence across racial/ethnic strata and socioeconomic status: a systematic review

OBJECTIVES

A higher incidence of breast cancer has been reported both in white women and women of higher socioeconomic status (SES) compared to women of other races and lower SES, respectively. We explored whether differences in SES can account for disparities in breast cancer incidence between races.

METHODS

We identified several studies published between 1990 and 2007 that addressed disparities in breast cancer incidence across racial and socioeconomic strata. For each study, we calculated incidence rate ratios (IRRs) for breast cancer incidence in the highest strata to lowest strata of SES for white, black, Hispanic and Asian/Pacific-Islander populations. We then used these IRRs to compare trends in SES and breast cancer incidence between races and across studies.

RESULTS

The studies we identified revealed that the magnitude of the disparity in breast cancer incidence between races decreases with increasing SES. While individual census-tract based studies' methods of assessing the association between SES and breast cancer incidence did not identify consistent trends between races, adjustment for risk factors closely correlated with SES eliminated the statistical differences in breast cancer incidence between women of white, Hispanic and Asian/Pacific-Islander, but not black, ethnicity.

CONCLUSION

We found that racial differences in breast cancer incidence can largely be accounted for by ethnic differences in SES among white, Hispanic and Asian/Pacific-Islander women, but not between these populations and black women. We further highlight important differences in methodology between previously published studies that may account for their disparate findings.

Population differences in breast cancer severity

Breast cancer incidence and mortality vary among different populations. African-American, Hispanic, Asian and Native American women have lower incidence but higher mortality compared with non-Hispanic white women. Explanations for the observed variation include social and economic factors such as education, income level, health insurance coverage, use of mammography, parity, breastfeeding and diet. Breast cancer may be a heterogeneous disease with different subtypes of tumors having different genetic and environmental risk factors. The difference in frequency of particular tumor subtypes between populations may explain some of the differences in incidence and mortality. Known genetic variants explain a small fraction of breast cancer cases, and so far there are no susceptibility genes that explain population differences in incidence and mortality. Studies evaluating the risk for particular tumor subtypes combining genetic and environmental variables and analyzing cases from different populations are needed to understand population differences in the severity of breast cancer.

Racial and ethnic differences in mammography use among U.S. women younger than age 40

OBJECTIVE

Evidence-based recommendations for routine breast cancer screening suggest that women begin mammography at age 40, although some women receive a mammogram before that age. Little is known about mammography use among younger women, especially with respect to race and ethnicity.

METHODS

We used data from the 2005 National Health Interview Survey to examine racial/ethnic differences in mammography use among U.S. women ages 30-39. We examined descriptive characteristics of women who reported ever having a mammogram, and used logistic regression to estimate associations between race/ethnicity and mammography use among women at average risk for breast cancer.

RESULTS

Our sample comprised 3,098 women (18% Hispanic, 13% non-Hispanic [NH] black, 69% NH white), of whom 29% reported having ever had a mammogram. NH black women were more likely than NH white women to report ever having a mammogram and receiving multiple mammograms before age 40 among women of average risk. Patterns of mammography use for Hispanic women compared to NH white women varied.

CONCLUSION

Findings suggest differential utilization of mammograms by race/ethnicity among women outside current recommendations and of average risk. Future studies should examine the role of practice patterns and patient-provider communication.

Mammographic breast density and race

OBJECTIVE

Women with increased mammographic breast density are known to be at higher risk of developing breast cancer. Reports of differences in breast density by race have implied that genetic and environmental factors may in part determine breast density. We first compared breast density among white, African American, and Asian women and then correlated breast density and race with age, body mass index (BMI), and breast or cup size.

MATERIALS AND METHODS

A retrospective review of data collected from 15,292 women was conducted. A stepwise multiple regression for an ordered response (breast density) was used to test for a relationship between race or ethnicity and breast density. We then determined whether differences in breast density by race might be caused by differences among races and ethnic groups in the age at imaging and BMI. We informally assessed the strength of the contribution of each term by means of the incremental change in the percent concordance. We also compared models using bra and cup sizes and age with models using BMI and age to try to determine whether the effects of breast size are local or systemic.

RESULTS

We did not find evidence that mammographic breast density differences exist across racial groups (p < 0.0001) other than those associated with BMI and age at screening. Ignoring age and BMI, breast density depends on race for all comparisons (p < 0.0001). To generalize, we found that breast density appears to be greater in Asian women and least in African American women. However, when controlling for BMI and age, breast density differences by race disappeared in all groups except Asians (p < 0.0001). In all racial groups, bra and cup size in addition to age correlated with breast density after controlling for BMI (p < 0.0001). Except in Asian women, in women of any racial group, age and any of the following parameters accounted for all of the breast density differences: BMI, bra size, and cup size.

CONCLUSION

Although breast density is associated with breast cancer risk, our results indicate that innate mammographic breast density differences across racial groups do not explain the risk differences known for the development of breast cancer. Age and BMI or age, bra size, and cup size can account for the reported density differences except among Asians. There may be no innate racial differences in breast density beyond those associated with racial differences in age and body habitus.

Physical activity, body mass index, and mammographic density in postmenopausal breast cancer survivors

PURPOSE

To investigate the association between physical activity, body mass index (BMI), and mammographic density in a racially/ethnically diverse population-based sample of 522 postmenopausal women diagnosed with stage 0-IIIA breast cancer and enrolled in the Health, Eating, Activity, and Lifestyle Study.

METHODS

We collected information on BMI and physical activity during a clinic visit 2 to 3 years after diagnosis. Weight and height were measured in a standard manner. Using an interview-administered questionnaire, participants recalled the type, duration, and frequency of physical activities they had performed in the last year. We estimated dense area and percentage density as a continuous measure using a computer-assisted software program from mammograms imaged approximately 1 to 2 years after diagnosis. Analysis of covariance methods were used to obtain mean density across WHO BMI categories and physical activity tertiles adjusted for confounders.

RESULTS

We observed a statistically significant decline in percentage density (P for trend = .0001), and mammographic dense area (P for trend = .0052), with increasing level of BMI adjusted for potential covariates. We observed a statistically significant decline in mammographic dense area (P for trend = .036) with increasing level of sports/recreational physical activity in women with a BMI of at least 30 kg/m2. Conversely, in women with a BMI less than 25 kg/m2, we observed a non-statistically significant increase in mammographic dense area and percentage density with increasing level of sports/recreational physical activity.

CONCLUSION

Increasing physical activity among obese postmenopausal breast cancer survivors may be a reasonable intervention approach to reduce mammographic density.

Pilot study of dietary influences on mammographic density in pre- and postmenopausal Hispanic and non-Hispanic white women

OBJECTIVE

The extent to which modifiable dietary factors may account for some of the variability demonstrated in mammographic density across ethnic groups is unknown. The purpose of this study was to provide pilot data describing the relationship between dietary variables and mammographic density in pre- and postmenopausal Hispanic and non-Hispanic white (NHW) women (N=238) ranging in age from 41 to 50 years (premenopausal only) or 56 to 70 years (postmenopausal only).

DESIGN

Using a cross-sectional design, computer-assisted density assessments were performed on mammograms of both breasts and averaged for analysis. The Arizona Food Frequency Questionnaire was used to estimate dietary intake.

RESULTS

Study participants were well educated and overweight, with mean mammographic densities ranging from 20.25% for postmenopausal Hispanic women to 46.94% for premenopausal NHW women. Hispanic women reported higher energy intake than NHW women, but energy-adjusted intake of other nutrients was generally comparable. There was preliminary evidence of ethnic variability in diet-mammographic density associations. Among premenopausal Hispanic women, density was inversely associated with dairy, calcium, and vitamin D intakes (P<or=0.05 for all). Among premenopausal NHW women, lower mammographic density was associated with greater intake of vegetables (P<or=0.05), and higher density was associated with greater fruit intake (P<or=0.05). Among postmenopausal Hispanic women, for every 4.54 increase in the polyunsaturated-to-saturated fat ratio, there was a 9.0% reduction in mammograph density.

CONCLUSIONS

These preliminary results suggest that a differential pattern of dietary nutrient associations with mammographic density could potentially exist among Hispanic and NHW women. These ethnic differences in diet and mammographic density associations need to be further explored in larger studies.

Estrogen-plus-progestin use and mammographic density in postmenopausal women: Women's Health Initiative randomized trial

BACKGROUND

Increased mammographic density reduces the sensitivity of screening mammography, is associated with increased breast cancer risk, and may be hormone related. We assessed the effect of estrogen-plus-progestin therapy on mammographic density.

METHODS

In a racially and ethnically diverse ancillary study of the Women's Health Initiative, we examined data from 413 postmenopausal women who had been randomly assigned to receive daily combined conjugated equine estrogens (0.625 mg) plus medroxyprogesterone acetate (i.e., progestin; 2.5 mg) (n = 202) or daily placebo (n = 211). We assessed the effect of estrogen plus progestin on measured mammographic percent density and abnormal findings over a 1-year and 2-year period. All tests of statistical significance were two-sided and were based on F tests or t tests from mixed-effects models.

RESULTS

Mean mammographic percent density increased by 6.0% at year 1, compared with baseline, in the estrogen-plus-progestin group but decreased by 0.9% in the placebo group (difference = 6.9%, 95% confidence interval [CI] = 5.3% to 8.5%; P < .001). The mean changes in mammographic density persisted but were attenuated slightly after 2 years, with an absolute increase of 4.9% in the estrogen-plus-progestin group and a decrease of 0.8% in the placebo group (difference = 5.7%, 95% CI = 4.3% to 7.3%; P < .001). These effects were consistent across racial/ethnic groups but were higher among women aged 70-79 years in the estrogen-plus-progestin group (mean increase at year 1 = 11.6%) than in the placebo group (mean decrease at year 1 = 0.1%) (difference of the means = 11.7%, 95% CI = 8.2% to 15.4%; P < .001, comparing across age groups). At year 1, women who were adherent to treatment in the estrogen-plus-progestin group had a mean increase in density of 7.7% (95% CI = 5.9% to 9.5%), and women in the placebo group had a mean decrease in density of 1.1% (95% CI = 0.3% to 1.9%). Use of estrogen plus progestin was associated with an increased risk of having an abnormal mammogram at year 1 (relative risk = 3.9, 95% CI = 1.5 to 10.2; P = .003), compared with placebo, that was not explained by an increase in density.

CONCLUSIONS

Use of up to 2 years of estrogen plus progestin was associated with increases in mammographic density.

Ethnicity and Breast Cancer: Factors Influencing Differences in Incidence and Outcome

BACKGROUND

The lower breast cancer incidence in minority women and the higher breast cancer mortality in African American women than in white women are largely unexplained. The influence of breast cancer risk factors on these differences has received little attention.

METHODS

Racial/ethnic differences in breast cancer incidence and outcome were examined in 156,570 postmenopausal women participating in the Women's Health Initiative. Detailed information on breast cancer risk factors including mammography was collected, and participants were followed prospectively for breast cancer incidence, pathological breast cancer characteristics, and breast cancer mortality. Comparisons of breast cancer incidence and mortality across racial/ethnic groups were estimated as hazard ratios (HRs) and 95% confidence intervals (CIs) from Cox proportional hazard models. Tumor characteristics were compared as odds ratios (ORs) and 95% confidence intervals in logistic regression models.

RESULTS

After median follow-up of 6.3 years, 3938 breast cancers were diagnosed. Age-adjusted incidences for all minority groups (i.e., African American, Hispanic, American Indian/Alaskan Native, and Asian/Pacific Islander) were lower than for white women, but adjustment for breast cancer risk factors accounted for the differences for all but African Americans (HR = 0.75, 95% CI = 0.61 to 0.92) corresponding to 29 cases and 44 cases per 10,000 person years for African American and white women, respectively. Breast cancers in African American women had unfavorable characteristics; 32% of those in African Americans but only 10% in whites were both high grade and estrogen receptor negative (adjusted OR = 4.70, 95% CI = 3.12 to 7.09). Moreover, after adjustment for prognostic factors, African American women had higher mortality after breast cancer than white women (HR = 1.79, 95% CI = 1.05 to 3.05) corresponding to nine and six deaths per 10 000 person-years from diagnosis in African American and white women, respectively.

CONCLUSION

Differences in breast cancer incidence rates between most racial/ethnic groups were largely explained by risk factor distribution except in African Americans. However, breast cancers in African American women more commonly had characteristics of poor prognosis, which may contribute to their increased mortality after diagnosis.