Alcohol intake over the life course and mammographic density

Cigarette smoking and mammographic breast density in post-menopausal women from the EPIC Florence cohort

Introduction

Cigarette smoking has been recognized as a risk factor for breast cancer (BC) also if the biological mechanism remains poorly understood. High mammographic breast density (MBD) is associated with BC risk and many BC risk factors, such as genetic, anthropometric, reproductive and lifestyle factors and age, are also able to modulate MBD. The aim of the present study was to prospectively explore, in post-menopausal women, the association between smoking habits and MBD, assessed using an automated software, considering duration and intensity of smoking.

Methods

The analysis was carried out in 3,774 women enrolled in the European Prospective Investigation into Cancer and Nutrition (EPIC) Florence cohort in 1993-98, participating in the 2004-06 follow up (FU) and with at least one full-field digital mammography (FFDM) performed after FU. For each woman, detailed information on smoking habits, anthropometry, lifestyle and reproductive history was collected at enrollment and at FU. Smoking information at baseline and at FU was integrated. The fully automated Volpara™ software was used to obtain total breast volume (cm3), absolute breast dense volume (DV, cm3) and volumetric percent density (VPD, %) from the first available FFDM (average 5.3 years from FU). Multivariable linear regression models were applied to evaluate the associations between smoking habits and VPD or DV.

Results

An inverse association between smoking exposure and VPD emerged (Diff% -7.96%, p <0.0001 for current smokers and -3.92%, p 0.01 for former smokers, compared with non-smokers). An inverse dose-response relationship with number of cigarettes/day, years of smoking duration and lifetime smoking exposure (pack-years) and a direct association with time since smoking cessation among former smokers emerged. Similar associations, with an attenuated effect, emerged when DV was considered as the outcome variable.

Discussion

This longitudinal study confirms the inverse association between active smoking, a known risk factor for BC, and MBD among post-menopausal women. The inclusion of smoking habits in the existing BC risk prediction models could be evaluated in future studies.

Long-Term Health Outcomes of Regular, Moderate Red Wine Consumption

Studies that are conducted to assess alcohol's long-term health outcomes generally report the results as a pooled analysis across all types of alcohol. Questions have been raised regarding potential health differences between types of alcohol, such as beer, wine, or spirits. While these three share the same alcohol in the form of ethanol, they differ in the other compounds they contain that are particular to each type of alcohol, specifically the polyphenols in red wine. The generalizability of pooled results may be limited due to the differences in health outcomes that may exist between different types of alcohol and lead to overall conclusions that differ from the subset analysis by type of alcohol that is often reported in the data tables of an article. The objective of this systematic review was to specifically address the assessment of the long-term health outcomes of regular, moderate, red wine consumption. PubMed was searched from 1987 through June 2023. Studies were included if they met all the following criteria: adult participants, red wine consumption and its frequency (close to daily), volume in moderation (1 glass/day for women, 2 glasses/day for men), and measurement of long-term (> 2 years) health outcomes. Nonclinical animal studies, or studies with an endpoint as a marker or biomarker, without a health outcome, of short duration (< 2 years), small size (< 25 subjects), a focus on binge drinking, no wine analysis performed, review articles, meta-analysis, or editorial/commentary were excluded. A total of 74 studies met the inclusion/exclusion criteria. Of these, 27 (36%) evaluated cancer outcomes, 14 (19%) evaluated cardiovascular outcomes, 10 (14%) evaluated mortality, 7 (9%) evaluated weight gain, 5 (7%) evaluated dementia, and the remaining 11 evaluated a variety of health outcomes. There were no studies that demonstrated an association between red wine consumption and negative health outcomes. Forty-seven studies demonstrated an association between red wine consumption and positive health outcomes, whereas 26 studies were neutral, and one had mixed results where women had a positive health outcome and men were neutral. All studies on mortality and dementia showed positive health outcomes. From this systematic review of the literature, there is no evidence of an association between moderate red wine consumption and negative health outcomes. Across the various outcomes assessed, a beneficial effect of moderate red wine consumption was consistently seen for mortality and dementia, along with certain cancers (e.g., non-Hodgkin lymphoma) and cardiovascular conditions (e.g., metabolic syndrome). For other health outcomes, the association was neutral, i.e., neither harmful nor beneficial. This review is not intended to encourage red wine consumption for health outcomes but rather to avoid discouraging moderate red wine consumption based on misunderstanding or misinterpretation of the red wine data due to the reporting of pooled data across all types of alcohol.

Association between wine consumption and cancer: a systematic review and meta-analysis

Background

Alcohol consumption is related to the risk of developing different types of cancer. However, unlike other alcoholic beverages, moderate wine drinking has demonstrated a protective effect on the risk of developing several types of cancer.

Objective

To analyze the association between wine consumption and the risk of developing cancer.

Methods

We searched the MEDLINE (through PubMed), Scopus, Cochrane, and Web of Science databases to conduct this systematic review and meta-analysis. Pooled relative risks (RRs) were calculated using the DerSimonian and Laird methods. I2 was used to evaluate inconsistency, the τ2 test was used to assess heterogeneity, and The Newcastle-Ottawa Quality Assessment Scale were applied to evaluate the risk of bias. This study was previously registered in PROSPERO, with the registration number CRD42022315864.

Results

Seventy-three studies were included in the systematic review, and 26 were included in the meta-analysis. The pooled RR for the effect of wine consumption on the risk of gynecological cancers was 1.03 (95% CI: 0.99, 1.08), that for colorectal cancer was 0.92 (95% CI: 0.82, 1.03), and that for renal cancer was 0.92 (95% CI: 0.81, 1.04). In general, the heterogeneity was substantial.

Conclusion

The study findings reveal no association between wine consumption and the risk of developing any type of cancer. Moreover, wine drinking demonstrated a protective trend regarding the risk of developing pancreatic, skin, lung, and brain cancer as well as cancer in general.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022315864, identifier CRD42022315864 (PROSPERO).

Bewertung des Rotweinkonsums im Rahmen der mediterranen Ernährung – Eine systematische Literaturanalyse

Hintergrund Die mediterrane Ernährung (MedE) zeigte in mehreren Studien einen präventiven Effekt hinsichtlich Typ 2 Diabetes, kardiovaskulären Erkrankungen und Tumorerkrankungen. Zur MedE wird in der Regel ein mäßiger Konsum von Wein, speziell Rotwein, empfohlen, dem selbst ein kardioprotektiver Effekt zugesprochen wird. Jedoch zeigen zahlreiche Studien, dass schon kleine Mengen Alkohol das Krebsrisiko erhöhen können. In der vorliegenden Arbeit soll eine Übersicht zur aktuellen Datenlage zum Zusammenhang zwischen dem Alkoholkonsum im Rahmen einer MedE, dem Krebsrisiko sowie dem Risiko für kardiovaskuläre Erkrankungen erstellt werden.

Methoden Im Rahmen einer systematischen Literaturrecherche in den Datenbanken PubMed und Scopus wurde nach den Schlagwörtern „diet, mediterranean“ und „alcohol drinking“ gesucht. Voraussetzung war, dass Angaben zur Art und Menge des konsumierten Alkohols im Rahmen der MedE vorlagen.

Ergebnisse Die Umsetzung der MedE kann sowohl das Risiko kardiometabolischer Erkrankungen als auch das Krebsrisiko u. a. für Brustkrebs senken. Moderater Alkoholkonsum zeigt protektive Effekte auf das Herz-Kreislauf-System, ist jedoch mit einem erhöhten Risiko für diverse Krebserkrankungen assoziiert. Mehrere Studien beschreiben eine Assoziation zwischen Alkoholkonsum und Brustkrebsinzidenz, wobei die Ergebnisse zwischen den Studien nicht einheitlich waren. Dabei kommt dem täglichen Glas Rotwein mit ca. 10–15 g Ethanol als vorherrschendem alkoholischen Getränk der Mittelmeerregion eine risikosenkende Wirkung zu.

Schlussfolgerung Moderater Konsum von Rotwein hat nach der vorliegenden systematischen Literaturanalyse, anders als andere alkoholische Getränke, einen protektiven Effekt auf kardiometabolische Erkrankungen und möglicherweise auch auf genetisch bedingten Brustkrebs, während der Konsum von anderen Alkoholgetränken die schützende Wirkung einer MedE möglicherweise reduziert.

Association between skeletal muscle mass and mammographic breast density

Mammographic density (MD) of the breast and body mass index (BMI) are inversely associated with each other, but have inconsistent associations with respect to the risk of breast cancer. Skeletal muscle mass index (SMI) has been considered to reflect a relatively accurate fat and muscle percentage in the body. So, we evaluated the relation between SMI and MD. A cross-sectional study was performed in 143,456 women who underwent comprehensive examinations from 2012 to 2016. BMI was adjusted to analyze whether SMI is an independent factor predicting dense breast. After adjustment for confounding factors including BMI, the odds ratios for MD for the dense breasts was between the highest and lowest quartiles of SMI at 2.65 for premenopausal women and at 2.39 for postmenopausal women. SMI was a significant predictor for MD, which could be due to the similar growth mechanism of the skeletal muscle and breast parenchymal tissue. Further studies are needed to understand the causal link between muscularity, MD and breast cancer risk.

Alcohol and Tobacco Use in Relation to Mammographic Density in 23,456 Women

BACKGROUND

Percent density (PD) is a strong risk factor for breast cancer that is potentially modifiable by lifestyle factors. PD is a composite of the dense (DA) and nondense (NDA) areas of a mammogram, representing predominantly fibroglandular or fatty tissues, respectively. Alcohol and tobacco use have been associated with increased breast cancer risk. However, their effects on mammographic density (MD) phenotypes are poorly understood.

METHODS

We examined associations of alcohol and tobacco use with PD, DA, and NDA in a population-based cohort of 23,456 women screened using full-field digital mammography machines manufactured by Hologic or General Electric. MD was measured using Cumulus. Machine-specific effects were estimated using linear regression, and combined using random effects meta-analysis.

RESULTS

Alcohol use was positively associated with PD (P trend = 0.01), unassociated with DA (P trend = 0.23), and inversely associated with NDA (P trend = 0.02) adjusting for age, body mass index, reproductive factors, physical activity, and family history of breast cancer. In contrast, tobacco use was inversely associated with PD (P trend = 0.0008), unassociated with DA (P trend = 0.93), and positively associated with NDA (P trend<0.0001). These trends were stronger in normal and overweight women than in obese women.

CONCLUSIONS

These findings suggest that associations of alcohol and tobacco use with PD result more from their associations with NDA than DA.

IMPACT

PD and NDA may mediate the association of alcohol drinking, but not tobacco smoking, with increased breast cancer risk. Further studies are needed to elucidate the modifiable lifestyle factors that influence breast tissue composition, and the important role of the fatty tissues on breast health.

Breast cancer prevention in premenopausal women: role of the Mediterranean diet and its components

Breast cancer (BC) is a growing public health concern in most developed and developing countries. Since an increasing number of patients with BC are diagnosed before the menopause and premenopausal women show a more aggressive phenotype, there is consistent interest in promoting prevention strategies in order to reduce the incidence of BC in the premenopause. The Mediterranean diet (MD) has been reported to have beneficial effect in terms of cancer prevention. This healthy dietary pattern consists primarily of foods having important antioxidant properties along with a favourable fatty acid profile, all associated with a reduced risk of cancer. Due to the large variability in study subject characteristics, the protective role of the MD on BC still remains controversial and studies that have investigated the association between adherence to the MD and risk of BC in premenopausal women are fewer than those in postmenopausal women. In addition, the possibility that the beneficial effects of the MD are due to a single component or might more probably derive from the synergic effects of all components of the MD remains a scantly explored field. Considering the increased risk of recurrence and mortality rate of BC in premenopausal women as compared with postmenopausal women, the aim of the present report is to provide a general overview of the current evidence on the relationship between BC and the MD specifically in premenopausal women, and to emphasise the potential role of the MD as an effective measure to reduce the risk of developing BC in premenopausal women.

Relationship of circulating insulin-like growth factor-I and binding proteins 1-7 with mammographic density among women undergoing image-guided diagnostic breast biopsy

Background

Mammographic density (MD) is a strong breast cancer risk factor that reflects fibroglandular and adipose tissue composition, but its biologic underpinnings are poorly understood. Insulin-like growth factor binding proteins (IGFBPs) are markers that may be associated with MD given their hypothesized role in breast carcinogenesis. IGFBPs sequester IGF-I, limiting its bioavailability. Prior studies have found positive associations between circulating IGF-I and the IGF-I:IGFBP-3 ratio and breast cancer risk. We evaluated the associations of IGF-I, IGFBP-3, and six other IGFBPs with MD.

Methods

Serum IGF measures were quantified in 296 women, ages 40–65, undergoing diagnostic image-guided breast biopsy. Volumetric density measures (MD-V) were assessed in pre-biopsy digital mammograms using single X-ray absorptiometry. Area density measures (MD-A) were estimated by computer-assisted thresholding software. Age, body mass index (BMI), and BMI²-adjusted linear regression models were used to examine associations of serum IGF measures with MD. Effect modification by BMI was also assessed.

Results

IGF-I and IGFBP-3 were not strongly associated with MD after BMI adjustment. In multivariable analyses among premenopausal women, IGFBP-2 was positively associated with both percent MD-V (β = 1.49, p value = 0.02) and MD-A (β = 1.55, p value = 0.05). Among postmenopausal women, positive relationships between IGFBP-2 and percent MD-V (β = 2.04, p = 0.003) were observed; the positive associations between IGFBP-2 and percent MD-V were stronger among lean women (BMI < 25 kg/m²) (β = 5.32, p = 0.0002; p interaction = 0.0003).

Conclusions

In this comprehensive study of IGFBPs and MD, we observed a novel positive association between IGFBP-2 and MD, particularly among women with lower BMI. In concert with in vitro studies suggesting a dual role of IGFBP-2 on breast tissue, promoting cell proliferation as well as inhibiting tumorigenesis, our findings suggest that further studies assessing the role of IGFBP-2 in breast tissue composition, in addition to IGF-1 and IGFBP-3, are warranted.

Electronic supplementary material

The online version of this article (10.1186/s13058-019-1162-8) contains supplementary material, which is available to authorized users.

Predictors of mammographic density among women with a strong family history of breast cancer

BACKGROUND

Mammographic density is one of the strongest risk factors for breast cancer. In the general population, mammographic density can be modified by various exposures; whether this is true for women a strong family history is not known. Thus, we evaluated the association between reproductive, hormonal, and lifestyle risk factors and mammographic density among women with a strong family history of breast cancer but no BRCA1 or BRCA2 mutation.

METHODS

We included 97 premenopausal and 59 postmenopausal women (age range: 27-68 years). Risk factor data was extracted from the research questionnaire closest in time to the mammogram performed nearest to enrollment. The Cumulus software was used to measure percent density, dense area, and non-dense area for each mammogram. Multivariate generalized linear models were used to evaluate the relationships between breast cancer risk factors and measures of mammographic density, adjusting for relevant covariates.

RESULTS

Among premenopausal women, those who had two live births had a mean percent density of 28.8% vs. 41.6% among women who had one live birth (P=0.04). Women with a high body weight had a lower mean percent density compared to women with a low body weight among premenopausal (17.6% vs. 33.2%; P=0.0006) and postmenopausal women (8.7% vs. 14.7%; P=0.04). Among premenopausal women, those who smoked for 14 years or longer had a lower mean dense area compared to women who smoked for a shorter duration (25.3cm² vs. 53.1cm²; P=0.002). Among postmenopausal women, former smokers had a higher mean percent density (19.5% vs. 10.8%; P=0.003) and dense area (26.9% vs. 16.4%; P=0.01) compared to never smokers. After applying the Bonferroni correction, the association between body weight and percent density among premenopausal women remained statistically significant.

CONCLUSIONS

In this cohort of women with a strong family history of breast cancer, body weight was associated with mammographic density. These findings suggest that mammographic density may explain the underlying relationship between some of these risk factors and breast cancer risk, and lend support for the inclusion of mammographic density into risk prediction models.

Can Dietary and Physical Activity Modifications Reduce Breast Density in Postmenopausal Women? The DAMA Study, a Randomized Intervention Trial in Italy

BACKGROUND

Few randomized trials have been carried out to evaluate the effect of lifestyle modifications on mammographic breast density (MBD). The randomized 2 × 2 factorial Diet, physical Activity and MAmmography trial aimed to evaluate whether MBD can be reduced in postmenopausal women with high baseline MBD by a 24-month dietary and/or physical activity (PA) interventions.

METHODS

We randomized healthy postmenopausal women, attending the Florence (Italy) mammographic screening program, ages 50 to 69 years, nonsmokers, with MBD > 50% and no recent hormone therapy, to (i) a dietary intervention focused on plant foods, with a low glycemic load, low in saturated fats and alcohol; (ii) a PA intervention combining daily moderate intensity activities and one weekly supervised session of more strenuous activity; (iii) both interventions; (iv) general recommendations. We evaluated changes in MBD based on Volpara estimates comparing baseline and follow-up digital mammograms by an intention-to-treat-analysis.

RESULTS

MBD measures were available for 226 participants. An interaction emerged between treatments and thus we run analyses by arms. A decrease in volumetric percent density emerged for women in the dietary intervention (ratio 0.91; 95% CI, 0.86-0.97; P = 0.002) and in the PA intervention arm (0.93; 95% CI, 0.87-0.98; P = 0.01) in comparison with controls. No clear effect emerged in the double intervention arm.

CONCLUSIONS

This intervention trial suggests that a 24-month dietary or PA intervention may reduce MBD in postmenopausal women.

IMPACT

A modification of dietary habits or an increase in PA in postmenopausal women may reduce MBD. Further studies are needed to confirm these findings for planning breast cancer preventive strategies.

Hair product use, age at menarche and mammographic breast density in multiethnic urban women

BACKGROUND

Select hair products contain endocrine disrupting chemicals (EDCs) that may affect breast cancer risk. We hypothesize that, if EDCs are related to breast cancer risk, then they may also affect two important breast cancer risk factors: age at menarche and mammographic breast density.

METHODS

In two urban female cohorts (N = 248): 1) the New York site of the National Collaborative Perinatal Project and 2) the New York City Multiethnic Breast Cancer Project, we measured childhood and adult use of hair oils, lotions, leave-in conditioners, root stimulators, perms/relaxers, and hair dyes using the same validated questionnaire. We used multivariable relative risk regression models to examine the association between childhood hair product use and early age at menarche (defined as <11 years of age) and multivariable linear regression models to examine the association between childhood and adult hair product use and adult mammographic breast density.

RESULTS

Early menarche was associated with ever use of childhood hair products (RR 2.3, 95% CI 1.1, 4.8) and hair oil use (RR 2.5, 95% CI 1.2, 5.2); however, additional adjustment for race/ethnicity, attenuated associations (hair products RR 1.8, 95% CI 0.8, 4.1; hair oil use RR 2.3, 95% CI 1.0, 5.5). Breast density was not associated with adult or childhood hair product or hair oil use.

CONCLUSIONS

If confirmed in larger prospective studies, these data suggest that exposure to EDCs through hair products in early life may affect breast cancer risk by altering timing of menarche, and may operate through a mechanism distinct from breast density.

Alcohol consumption across the life course and mammographic density in premenopausal women

PURPOSE

Consumption of alcoholic beverages during adolescence and early adulthood has been consistently associated with higher breast cancer risk. The influence of alcohol consumption early in life on mammographic breast density, a marker of breast cancer risk, is inconclusive. This study examined associations of alcohol consumption across the life course with premenopausal mammographic density.

METHODS

The study population included 1211 premenopausal women in the Nurses' Health Study II without cancer, who recalled their alcohol consumption at age 15 through enrollment in 1989 (baseline), and had mammograms available. Recent alcohol consumption was updated over follow-up. Percent and absolute measures of mammographic density were quantified on digitized film mammograms. Generalized linear regression was used to assess associations.

RESULTS

There were no notable differences in any of the three density measures for alcohol consumption at any age (15-17, 18-22, 23-30, and 31-mammogram). Neither alcohol consumption before first pregnancy nor after first pregnancy was significantly associated with any of the three density measures.

CONCLUSIONS

Moderate alcohol consumption during different age intervals during adolescence and early adulthood was not associated with mammographic density in premenopausal women.

Alcohol consumption and mammographic density in the Danish Diet, Cancer and Health cohort

PURPOSE

We examined the association between alcohol consumption and mammographic density (MD) considering in detail the time of exposure and the type of alcohol.

METHODS

Of 5,356 women (4,489 post-menopausal) from the Danish Diet, Cancer and Health cohort (1993-1997) who attended mammographic screening in Copenhagen (1993-2001), we used MD (mixed/dense or fatty) assessed at the first screening after cohort entry. Alcohol consumption was assessed at the time of recruitment. Logistic regression was used to estimate associations [odds ratios (OR), 95% confidence intervals (CI)] between alcohol consumption and MD.

RESULTS

The mean age was 56.2 years, 56.5% of women had mixed/dense MD, and 91.8% were alcohol consumers. There was no association between current alcohol consumption and MD at baseline (age 50-65, on average 1 year before MD assessment) neither between age at drinking initiation and MD, in the fully adjusted model. There was a borderline statistically significantly increased OR of having mixed/dense MD in women who consumed > 7 drinks/week at age 20-29 (1.31, 95% CI 1.00-1.72) compared to non-drinkers in this age group, and no effect of drinking at age 30-39, 40-49 or after > 50 years, when adjusting for current drinking. However, when considering different types of alcohol, drinking spirits at age 20-29 was positively associated with mixed/dense breast (3-7 drinks/week: OR 1.74, 95% CI 1.12-2.72); >7 drinks/week: (OR 1.76, 95% CI 0.73-4.23). No consistent pattern was found with beer, wine, or fortified wine.

CONCLUSIONS

We found higher MD among women with high alcohol consumption in early adulthood (ages 20-29), in those drinking spirits.

Dose-Dependent Associations between Wine Drinking and Breast Cancer Risk - Meta-Analysis Findings

PURPOSE

To investigate any potential association between wine and breast cancer risk.

MATERIALS AND METHODS

We quantitatively assessed associations by conducting a meta-analysis based on evidence from observational studies. In May 2014, we performed electronic searches in PubMed, EmBase and the Cochrane Library to identify studies examining the effect of wine drinking on breast cancer incidence. The relative risk (RR) or odds ratio (OR) were used to measure any such association.

RESULTS

The analysis was further stratified by confounding factors that could influence the results. A total of twenty-six studies (eight case-control and eighteen cohort studies) involving 21,149 cases were included in our meta-analysis. Our study demonstrated that wine drinking was associated with breast cancer risk. A 36% increase in breast cancer risk was observed across overall studies based on the highest versus lowest model, with a combined RR of 1.0059 (95%CI 0.97-1.05) in dose-response analysis. However, 5 g/d ethanol from wine seemed to have protective value from our non-linear model.

CONCLUSIONS

Our findings indicate that wine drinking is associated with breast cancer risk in a dose-dependent manner. High consumption of wine contributes to breast cancer risk with protection exerted by low doses. Further investigations are needed for clarification.

Early life socioeconomic environment and mammographic breast density

Background

Early life social environment may influence breast cancer through shaping risk factors operating in early life, adolescence and adulthood, or may be associated with breast cancer risk independent of known risk factors. We investigated the associations between early life socioeconomic status (SES) and mammographic density, a strong risk factor for breast cancer, and the extent to which these associations were independent of risk factors across the lifecourse.

Methods

We used data from an adult follow-up study of two U.S. birth cohorts of women (average age = 43 years) with prospectively collected data starting during the pregnancy of the mother and continuing through early childhood of the offspring. We collected data on factors in later life periods through computer-assisted interviews with the offspring as adults, and obtained routine clinical mammograms for measurement of percent density and dense and nondense breast areas using a computer assisted method. We used generalized estimating equation models for multivariable analysis to account for correlated data for sibling sets within the study sample (n = 700 composed of 441 individuals and 127 sibling sets).

Results

Highest vs. lowest family income level around the time of birth was associated with smaller dense breast area after adjustment for early life factors (e.g., birthweight, maternal smoking during pregnancy) and risk factors in later life periods, including adult body mass index (BMI) and adult SES (β = −8.2 cm², 95% confidence interval [CI]: −13.3, −3.2). Highest vs. lowest parental educational attainment was associated with higher percent density in models that adjusted for age at mammogram and adult BMI (e.g., β = 4.8, 95% CI = 0.6, 9.1 for maternal education of college or higher degree vs. less than high school), but the association was attenuated and no longer statistically significant after further adjustment for early life factors. There were no associations between early life SES indicators and non-dense area after adjustment for adult BMI. Neither adult education nor adult income was statistically significantly associated with any measure of mammographic density after adjusting for age and adult BMI.

Conclusions

We did not observe consistent associations between different measures of early life SES and mammographic density in adulthood.

Early life growth, socioeconomic status, and mammographic breast density in an urban US birth cohort

PURPOSE

Rapid infant and childhood growth has been associated with chronic disease later in life, including breast cancer. Early life socioeconomic status (SES) influences childhood growth, but few studies have prospective measures from birth to consider the effects of early life growth and SES on breast cancer risk.

METHODS

We used prospectively measured early life SES and growth (percentile weight change in height and weight between each pair of consecutive time points at birth, 4 months, 1 and 7 years). We performed linear regression models to obtain standardized estimates of the association between 1 standard deviation increase in early life SES and growth and adult mammographic density (MD), a strong risk factor for breast cancer, in a diverse birth cohort (n = 151; 37% white, 38% black, 25% Puerto Rican; average age at mammogram = 42.4).

RESULTS

In models adjusted for race/ethnicity, prenatal factors, birthweight, infant and childhood growth, and adult body mass index, percentile weight change from 1 year to 7 years was inversely associated with percent MD (standardized coefficient (Stdβ) = -0.28, 95% CI: -0.55 to -0.01), and higher early life SES was positively associated with percent MD (Stdβ = 0.24, 95% CI: 0.04-0.43). Similar associations were observed for dense area, but those estimates were not statistically significant.

CONCLUSIONS

These results suggest opposite and independent effects of early life SES and growth on MD.

Alcohol intake from early adulthood to midlife and mammographic density

PURPOSE

Moderate alcohol consumption (15 g/day) has been consistently associated with increased breast cancer risk; however, the association between alcohol and mammographic density, a strong marker of breast cancer risk, has been less consistent. Less is known about the effect of patterns of alcohol intake across the lifecourse.

METHODS

Using the Early Determinants of Mammographic Density study, an adult follow-up of women born in two US birth cohorts (n = 697; Collaborative Perinatal Project in Boston and Providence sites and the Childhood Health and Development Studies in California), we examined the association between alcohol intake in early adulthood (ages 20-29 years) and at time of interview and mammographic density (percent density and total dense area). We report the difference between nondrinkers and three levels of alcohol intake. We considered confounding by age at mammogram, body mass index, geographic site, race/ethnicity, and reproductive characteristics.

RESULTS

Seventy-nine percent of women reported ever consuming alcohol. Compared to nondrinkers in early adulthood, we observed an inverse association between >7 servings/week and percent density in fully adjusted models (β = -5.1, 95% CI -8.7, -1.5; p for trend = <0.01). Associations with dense area were inverse for the highest category of drinking in early adulthood but not statistically significant (p for trend = 0.15). Compared to noncurrent drinkers, the association for current intake of >7 servings/week and percent density was also inverse (β = -3.1, 95% CI -7.0, 0.8; p for trend = 0.01). In contrast, moderate alcohol intake (>0-≤7 servings/week) in either time period was positively associated with dense area; but associations were not statistically significant in fully adjusted models.

CONCLUSIONS

Our study does not lend support to the hypothesis that the positive association between alcohol intake and breast cancer risk is through increasing mammographic density.

Links between alcohol consumption and breast cancer: a look at the evidence

Alcohol consumption by adult women is consistently associated with risk of breast cancer. Several questions regarding alcohol and breast cancer need to be addressed. Menarche to first pregnancy represents a window of time when breast tissue is particularly susceptible to carcinogens. Youth alcohol consumption is common in the USA, largely in the form of binge drinking and heavy drinking. Whether alcohol intake acts early in the process of breast tumorigenesis is unclear. This review aims to focus on the influences of timing and patterns of alcohol consumption and the effect of alcohol on intermediate risk markers. We also review possible mechanisms underlying the alcohol-breast cancer association.

Alcohol consumption, endogenous estrogen and mammographic density among premenopausal women

Introduction

Alcohol consumption may promote aromatization of androgens to estrogens, which may partly explain the observations linking alcohol consumption to higher breast cancer risk. Whether alcohol consumption is associated with endogenous estrogen levels, and mammographic density phenotypes in premenopausal women remains unclear.

Methods

Alcohol consumption was collected by self-report and interview, using semi quantitative food frequency questionnaires, and a food diary during seven days of a menstrual cycle among 202 premenopausal women, participating in the Energy Balance and Breast Cancer Aspects (EBBA) study I. Estrogen was assessed in serum and daily in saliva across an entire menstrual cycle. Computer-assisted mammographic density (Madena) was obtained from digitized mammograms taken between days 7–12 of the menstrual cycle. Multivariable regression models were used to investigate the associations between alcohol consumption, endogenous estrogen and mammographic density phenotypes.

Results

Current alcohol consumption was positively associated with endogenous estrogen, and absolute mammographic density. We observed 18 % higher mean salivary 17β-estradiol levels throughout the menstrual cycle, among women who consumed more than 10 g of alcohol per day compared to women who consumed less than 10 g of alcohol per day (p = 0.034). Long-term and past-year alcohol consumption was positively associated with mammographic density. We observed a positive association between alcohol consumption (past year) and absolute mammographic density; high alcohol consumers (≥7 drinks/week) had a mean absolute mammographic density of 46.17 cm² (95 % confidence interval (CI) 39.39, 52.95), while low alcohol consumers (<1 drink/week) had a mean absolute mammographic density of 31.26 cm² (95 % CI 25.89, 36.64) (p-trend 0.001). After adjustments, high consumers of alcohol (≥7 drinks/week), had 5.08 (95 % CI 1.82, 14.20) times higher odds of having absolute mammographic density above median (>32.4 cm²), compared to low (<1 drink/week) alcohol consumers.

Conclusion

Alcohol consumption was positively associated with daily endogenous estrogen levels and mammographic density in premenopausal women. These associations could point to an important area of breast cancer prevention.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-015-0620-1) contains supplementary material, which is available to authorized users.

Background risk of breast cancer influences the association between alcohol consumption and mammographic density

Background:

Alcohol consumption has been suggested to increase risk of breast cancer through a mechanism that also increases mammographic density. Whether the association between alcohol consumption and mammographic density is modified by background breast cancer risk has, however, not been studied.

Methods:

We conducted a population-based cross-sectional study of 53 060 Swedish women aged 40–74 years. Alcohol consumption was assessed using a web-based self-administered questionnaire. Mammographic density was measured using the fully-automated volumetric Volpara method. The Tyrer–Cuzick prediction model was used to estimate risk of developing breast cancer in the next 10 years. Linear regression models were used to evaluate the association between alcohol consumption and volumetric mammographic density and the potential influence of Tyrer–Cuzick breast cancer risk.

Results:

Overall, increasing alcohol consumption was associated with higher absolute dense volume (cm³) and per cent dense volume (%). The association between alcohol consumption and absolute dense volume was most pronounced among women with the highest (⩾5%) Tyrer–Cuzick 10-year risk. Among high-risk women, women consuming 5.0–9.9, 10.0–19.9, 20.0–29.9, and 30.0–40.0 g of alcohol per day had 2.6 cm³ (95% confidence interval (CI), 0.2–4.9), 2.9 cm³ (95% CI, −0.6 to 6.3), 4.6 cm³ (95% CI, 1.5–7.7), and 10.8 cm³ (95% CI, 4.8–17.0) higher absolute dense volume, respectively, as compared with women abstaining from alcohol. A trend of increasing alcohol consumption and higher absolute dense volume was seen in women at low (⩽3%) risk, but not in women at moderate (3.0–4.9%) risk.

Conclusion:

Alcohol consumption may increase breast cancer risk through increasing mammographic density, particularly in women at high background risk of breast cancer.

The association of alcohol consumption with mammographic density in a multiethnic urban population

Background

Alcohol consumption is associated with higher breast cancer risk. While studies suggest a modest association between alcohol intake and mammographic density, few studies have examined the association in racial/ethnic minority populations.

Methods

We assessed dense breast area and total breast area from digitized film mammograms in an urban cohort of African American (42%), African Caribbean (22%), white (22%), and Hispanic Caribbean (9%) women (n = 189, ages 40-61). We examined the association between alcohol intake and mammographic density (percent density and dense area). We used linear regression to examine mean differences in mammographic density across alcohol intake categories. We considered confounding by age, body mass index (BMI), hormone contraceptive use, family history of breast cancer, menopausal status, smoking status, nativity, race/ethnicity, age at first birth, and parity.

Results

Fifty percent currently consumed alcohol. Women who consumed >7 servings/week of alcohol, but not those consuming ≤7 servings/week, had higher percent density compared to nondrinkers after full adjustments (servings/week >7 β = 8.2, 95% Confidence Interval (CI) 1.8, 14.6; ≤7 β = -0.5, 95% CI -3.7, 2.8). There was a positive association between high alcohol intake and dense area after full adjustments (servings/week >7 β = 5.8, 95% CI -2.7, 14.2; ≤7 β = -0.1, 95% CI -4.4, 4.2). We did not observe race/ethnicity modification of the association between alcohol intake and percent density. In women with a BMI of <25 kg/m², drinkers consuming >7 servings/week of alcohol had a 17% increase in percent density compared to nondrinkers (95% CI 5.4, 29.0) and there was no association in women with a BMI ≥ 25 kg/m² (BMI ≥ 25-30 kg/m² > 7 β = 5.1, 95% CI -8.5, 18.7 and BMI > 30 kg/m² > 7 β = 0.5, 95% CI -6.5, 7.5) after adjusting for age and BMI (continuous).

Conclusion

In a racially/ethnically diverse cohort, women who consumed >7 servings/week of alcohol, especially those with a BMI < 25 kg/m², had higher percent density.

Alcohol intake stimulates epithelial proliferation in an authentic model of the human breast

The voluntary consumption of alcohol by humans is a modifiable lifestyle factor that has been consistently linked to a woman's risk of developing breast cancer. We have used an animal model that closely recapitulates breast development in humans to study the effect of alcohol intake on breast growth and morphology. Pubertal female pigs were fed alcohol for 4-5 weeks at 19-21% of total caloric intake, which led to average blood alcohol concentrations of 115-130mg/dL. Alongside increased liver mass, alcohol intake promoted the formation of distended ductules within lobular units in association with increased epithelial proliferation. Alcohol consumption also increased phosphorylation of the transcription factor STAT5 in the mammary epithelium, but did not lead to any evidence of precocious lactogenesis. In conclusion, feeding alcohol to female pigs having a similar physiology and mammary gland morphology to humans during a reproductive state equivalent to human adolescence leads to increased mammary gland proliferation and development of atypical lobular structures. These changes may phenocopy how alcohol intake increases the risk for developing breast cancer in humans.

Breast cancer susceptibility variants and mammographic density phenotypes in norwegian postmenopausal women

BACKGROUND

Mammographic density (MD) is one of the strongest known breast cancer risk factors. Twin studies have suggested that a large part of the variation in MD is genetically determined. We hypothesized that breast cancer susceptibility variants may affect MD, and that their effects may be modified by nongenetic factors.

METHODS

We assessed MD, using a computer-assisted method, on 2,348 postmenopausal Caucasian women (50-69 years) who participated in the Norwegian Breast Cancer Screening Program (NBCSP) in 2004 or 2006-07. We used linear regression (additive models) to determine the association between each SNP and MD, adjusting for age, body mass index (BMI), and study. We evaluated MD associations with 17 established breast cancer SNPs, overall, and by strata defined by non-genetic factors.

RESULTS

Two variants, 6q25.1-rs9383938 and TXNRD2-rs8141691, were statistically significantly associated with percent MD (P = 0.019 and 0.03, respectively), with the 6q25.1-rs9383938 association being consistent with the SNP effect on breast cancer risk. The effect of 6q25.1-rs3734805 on percent MD varied between parous and nulliparous women (Pinteraction = 0.02), whereas the effects of 9q31.2-rs865686 and MRPS30:FGF10-rs4415084 differed across strata of BMI (Pinteraction = 0.01 and 0.005, respectively). There was no evidence of effect modification by estrogen and progestin therapy use or alcohol consumption.

CONCLUSION

This study provides novel evidence of shared genetic risk factors between MD and breast cancer and of possible MD genetic-environmental interactions.

IMPACT

Although the results may be chance findings, they nevertheless highlight the need to investigate interactions with nongenetic factors in studies on the genetics of MD.

Alcohol Intake and Breast Cancer Risk: Weighing the Overall Evidence

Moderate alcohol consumption has been linked to an approximate 30-50% increased risk in breast cancer. Case-control and cohort studies have consistently observed this modest increase. We highlight recent evidence from molecular epidemiologic studies and studies of intermediate markers like mammographic density that provide additional evidence that this association is real and not solely explained by factors/correlates of the exposure and outcome present in non-randomized studies. We also review evidence from studies of higher risk women including BRCA1 and BRCA2 mutation carriers. Given the incidence of heart disease is higher than breast cancer and modest alcohol consumption is associated with reduced risk of heart disease, we examine the latest evidence to evaluate if alcohol reduction should be targeted to women at high risk for breast cancer. We also review the most recent evidence on the effect of alcohol use on tumor recurrence and survival for those diagnosed with breast cancer.

Alcohol Intake and Breast Cancer Risk: Weighing the Overall Evidence

Moderate alcohol consumption has been linked to an approximate 30-50% increased risk in breast cancer. Case-control and cohort studies have consistently observed this modest increase. We highlight recent evidence from molecular epidemiologic studies and studies of intermediate markers like mammographic density that provide additional evidence that this association is real and not solely explained by factors/correlates of the exposure and outcome present in non-randomized studies. We also review evidence from studies of higher risk women including BRCA1 and BRCA2 mutation carriers. Given the incidence of heart disease is higher than breast cancer and modest alcohol consumption is associated with reduced risk of heart disease, we examine the latest evidence to evaluate if alcohol reduction should be targeted to women at high risk for breast cancer. We also review the most recent evidence on the effect of alcohol use on tumor recurrence and survival for those diagnosed with breast cancer.

Alcohol intake over the life course and breast cancer survival in Western New York exposures and breast cancer (WEB) study: quantity and intensity of intake

Alcohol intake is a risk factor for breast cancer, but the association between alcohol and mortality among breast cancer survivors is poorly understood. We examined the association between alcohol intake from all sources, assessed by cognitive lifetime drinking history, and all-cause and breast cancer mortality among women with breast cancer (N = 1,097) who participated in a population-based case-control study. Vital status was ascertained through 2006 using the National Death Index. Using Cox proportional hazards models, we computed hazard ratios for all-cause and breast cancer mortality in association with alcohol intake. We examined lifetime volume and intensity (drinks per drinking day) of alcohol consumption as well as drinking status during various life periods. Analyses were stratified by menopausal status. After adjustment for total intake, postmenopausal women with consumption of four or more drinks per drinking day over their lifetimes were nearly three times more likely to die from any cause compared to abstainers (HR 2.94, 95 % CI 1.31, 6.62). There was a similar but non-significant association with breast cancer mortality (HR 2.68, 95 % CI 0.94, 7.67). Postmenopausal women who drank one drink or fewer per drinking day between menarche and first birth had a significantly decreased hazard of all-cause (HR 0.54, 95 % CI 0.31, 0.95) and breast cancer mortality (HR 0.27, 95 % CI 0.09, 0.77). Premenopausal breast cancer survival was not associated with drinking intensity. We observed no associations between drinking status or total volume of alcohol intake and breast cancer or all-cause mortality. High-intensity alcohol consumption may be associated with decreased survival in postmenopausal women with breast cancer. Low-intensity alcohol consumption between menarche and first birth may be inversely associated with all-cause and breast cancer mortality; this period may be critical for development of and survival from breast cancer. Intensity of alcohol intake may be a more important factor than absolute volume of intake on survival in women with breast cancer.

Association of Mediterranean diet, dietary supplements and alcohol consumption with breast density among women in South Germany: a cross-sectional study

BACKGROUND

Effects of dietary factors, such as adherence to Mediterranean diet, multivitamin-multimineral supplements use and alcohol consumption on mammographic breast density, an important biomarker of breast cancer risk, are not sufficiently consistent to elaborate preventive recommendations. This study aims to investigate the association between current diet and mammographic density.

METHODS

We performed a cross-sectional study in 424 pre- and post-menopausal women aged 21 to 84 years. Current Mediterranean dietary pattern, multivitamin-multimineral supplements use, alcohol consumption and potential confounders were assessed with a self-administered questionnaire in the University Hospital Ulm (2007-2008). Radiologists evaluated mammographic density according to the American College of Radiology (ACR) classification, which was summarized in low = ACR1/2 and high = ACR3/4 mammographic density. Logistic regression models were used to assess the association between current diet and mammographic density.

RESULTS

Adherance to Mediterranean dietary pattern was inversely associated with mammographic density in the models adjusted for age and BMI (per 1 unit increase of score OR 0.95; 95%CI 0.90-0.997). Current use of multivitamin-multimineral supplements was also inversely associated with mammographic density (OR 0.53; 95%CI 0.34-0.83). Further adjustment revealed similar point estimates but the associations were no longer statistically significant. Compared to non-drinkers, excessive alcohol consumption (<10 g/d) was positively associated with mammographic density (OR 1.47; 95%CI 0.82-2.63).

CONCLUSIONS

Our results show that dietary factors are associated with mammographic density. Adherence to Mediterranean diet and current use of multivitamin-multimineral supplements could be inversely associated with mammographic density and may suggest a protective effect against breast cancer, whereas high alcohol consumption was associated with increased mammographic density.

Identification of a novel Calotropis procera protein that can suppress tumor growth in breast cancer through the suppression of NF-κB pathway

Breast cancer is the most common cancer among women. To date, improvements in hormonal and cytotoxic therapies have not yet led to a sustained remission or cure. In the present study, we investigated the in vitro and in vivo antitumor activities of a novel Calotropis procera protein (CP-P) isolated from root bark. CP-P protein inhibited the proliferation and induced apoptosis of breast cancer cells through the suppression of nuclear factor kappaB (NF-kB) activation. CP-P, when administered individually or in combination with cyclophosphamide (CYC, 0.2 mg/kg) to rats with 7, 12-dimethyl benz(a)anthracene (DMBA)-induced breast cancer decreased tumor volume significantly without affecting the body weight. To elucidate the anticancer mechanism of CP-P, antioxidant activities such as superoxide dismutase (SOD), catalase (CAT), glutathione-s-transferase (GST) and non-enzymatic antioxidant - reduced glutathione (GSH), vitamin E and C generation in the breast were analyzed by various assays. SOD, CAT, GST, GSH, vitamin E and C levels were high in combination-treated groups (CP-P+CYC) versus the CYC alone-treated groups. Also, the combination was more effective in down-regulating the expression of NF-kB-regulated gene products (cyclin D1 and Bcl-2) in breast tumor tissues. Our findings indicate that CP-P possesses significant antitumor activity comparable to a commonly used anticancer drug, cyclophosphamide, and may form the basis of a novel therapy for breast cancer.

Red versus white wine as a nutritional aromatase inhibitor in premenopausal women: a pilot study

BACKGROUND

An increased risk of breast cancer is associated with alcohol consumption; however, it is controversial whether red wine increases this risk. Aromatase inhibitors (AIs) prevent the conversion of androgens to estrogen and occur naturally in grapes, grape juice, and red, but not white wine. We tested whether red wine is a nutritional AI in premenopausal women.

METHODS

In a cross-over design, 36 women (mean age [SD], 36 [8] years) were assigned to 8 ounces (237 mL) of red wine daily then white wine for 1 month each, or the reverse. Blood was collected twice during the menstrual cycle for measurement of estradiol (E2), estrone (E1), androstenedione (A), total and free testosterone (T), sex hormone binding globulin (SHBG), luteinizing hormone (LH), and follicle stimulating hormone (FSH).

RESULTS

Red wine demonstrated higher free T vs. white wine (mean difference 0.64 pg/mL [0.2 SE], p=0.009) and lower SHBG (mean difference -5.0 nmol/L [1.9 SE], p=0.007). E2 levels were lower in red vs. white wine but not statistically significant. LH was significantly higher in red vs. white wine (mean difference 2.3 mIU/mL [1.3 SE], p=0.027); however, FSH was not.

CONCLUSION

Red wine is associated with significantly higher free T and lower SHBG levels, as well as a significant higher LH level vs. white wine in healthy premenopausal women. These data suggest that red wine is a nutritional AI and may explain the observation that red wine does not appear to increase breast cancer risk.

Alcohol intake and mammographic density in postmenopausal Norwegian women

Mammographic density is a strong risk factor for breast cancer. While alcohol intake has been associated with increased breast cancer risk, the association between alcohol consumption and mammographic density is not clear. We assessed the association between alcohol consumption and mammographic density among women who participated in the Norwegian Breast Cancer Screening Program in 2004. Mammographic density was assessed on digitized mammograms from 2,251 postmenopausal women aged 50-69 years, using a computer assisted method. Current intake of beer, wine (red and white), and liquor was assessed using a validated food frequency questionnaire. Non-drinkers were defined as complete abstainers (i.e., those who reported no intake of any type of alcohol). We used multivariate linear regression models to estimate least square means of percent mammographic density by categories of alcohol intake with adjustment for potential confounders. We also checked for possible effect modification by stratifying the analyses by age, body mass index, and hormone therapy. The mean percent mammographic density was almost similar for drinkers 18.3% (95% CI: 17.6-18.9%) and non-drinkers 17.8% (95% CI: 16.1-19.4%) (P = 0.59). There was no indication that amount of alcohol consumed was associated with percent mammographic density, with a mean percent density among women with the highest intake (>90 g of alcohol per week) of 18.2% (95% CI: 16.9-19.0%), only slightly different from that of non-drinkers 18.3% (17.3-19.6%) (P for trend = 0.99). There was no association between any type of alcohol consumed and mammographic density.There was no effect modification by body mass index, age, or hormone therapy use. We found no evidence of an association between alcohol intake and percent mammographic density.

Alcohol, tobacco, and mammographic density: a population-based study

Mammographic density (MD), or the proportion of the breast with respect to its overall area that is composed of dense tissue, is a strong risk factor for breast cancer. Studies support a positive association of mammographic density and alcohol drinking. This was a cross-sectional multicenter study based on 3584 women, aged 45-68 years, recruited from seven screening centers within the Spanish breast cancer screening program network. The association between MD, alcohol consumption and tobacco use was evaluated by using ordinal logistic models with random center-specific intercepts. We found a weak positive association between current alcohol intake and higher MD, with current alcohol consumption increasing the odds of high MD by 13% (OR = 1.13; 95% CI 0.99-1.28) and high daily grams of alcohol being positively associated with increased MD (P for trend = 0.045). There were no statistically significant differences in MD between smokers and non-smokers. Nevertheless, increased number of daily cigarettes and increased number of accumulated lifetime cigarettes were negatively associated with high MD (P for trend 0.017 and 0.021). The effect of alcohol on MD was modified by menopausal status and tobacco smoking: whereas, alcohol consumption and daily grams of alcohol were positively associated with higher MD in postmenopausal women and in women who were not currently smoking, alcohol consumption had no effect on MD in premenopausal women and current smokers. Our results support an association between recent alcohol consumption and high MD, characterized by a modest increase in risk at low levels of current consumption and a decrease in risk among heavier drinkers. Our study also shows how the effects of alcohol in the breast can be modified by other factors, such as smoking.

Components of an anticancer diet: dietary recommendations, restrictions and supplements of the Bill Henderson Protocol

The use of complementary and alternative medicines including dietary supplements, herbals and special diets to prevent or treat disease continues to be popular. The following paper provides a description of an alternative dietary approach to the self-management and treatment of cancer, the Bill Henderson Protocol (BHP). This diet encourages daily intake of raw foods, a combination of cottage cheese and flaxseed oil and a number of supplements. Some foods and food groups are restricted (e.g., gluten, meat, dairy). Early background theory that contributed to the protocol’s development is presented as is a summary of relevant evidence concerning the anti-cancer fighting properties of the individual components. Supplement intake is considered in relation to daily recommended intakes. Challenges and risks to protocol adherence are discussed. As with many complementary and alternative interventions, clear evidence of this dietary protocol’s safety and efficacy is lacking. Consumers of this protocol may require guidance on the ability of this protocol to meet their individual nutritional needs.

Prospective study of adolescent alcohol consumption and risk of benign breast disease in young women

OBJECTIVE

To investigate prospectively, using alcoholic beverage consumption data collected in real time, the association between adolescent drinking and risk of biopsy-confirmed benign breast disease (BBD) in young women.

PARTICIPANTS AND METHODS

The Growing Up Today Study is a prospective cohort study of US girls, aged 9 to 15 years at baseline, with annual questionnaires from 1996 through 2001, followed by questionnaires in 2003, 2005, and 2007. On the 2003 survey, the participants (then aged 16-23 years) provided information about their alcoholic beverage consumption in the previous year. On the 2005 and 2007 surveys, a total of 6899 women (aged 18-27 years) reported whether a health care provider had ever diagnosed them with BBD (n = 147 cases) and whether it was confirmed by biopsy (n = 67 cases); 6752 women reported never being diagnosed with BBD.

RESULTS

Adjusted for age and BMI, quantity of alcohol consumed was associated with increased risk of biopsy-confirmed BBD (odds ratio: 1.50 per drink per day [95% confidence interval: 1.19-1.90]). Girls who typically drank 6 or 7 days/week were at higher risk (odds ratio: 5.50 [95% confidence interval: 1.23-24.53]) compared with those who never drank or who drank less than once per week.

CONCLUSIONS

Higher amounts consumed, and more frequent consumption, of alcoholic beverages in adolescence may increase the occurrence of BBD in young women. Advising teenagers to avoid alcoholic beverages, along with smoking and sun exposure, may reduce cancer incidence in adulthood.