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

Benign breast disease and breast cancer risk in African women: a case-control study

PURPOSE

To examine the association between benign breast disease (BBD) and breast cancer (BC) in a heterogeneous population of African women.

METHODS

BC cases and controls were enrolled in three sub-Saharan African countries, Nigeria, Cameroon, and Uganda, between 1998 and 2018. Multivariable logistic regression was used to test the association between BBD and BC. Risk factors dually associated with BBD and BC were selected. Using a parametric mediation analysis model, we assessed if selected BC risk factors were mediated by BBD.

RESULTS

Of 6,274 participants, 55.6% (3,478) were breast cancer cases. 360 (5.7%) self-reported BBD. Fibroadenoma (46.8%) was the most commonly reported BBD. Women with a self-reported history of BBD had greater odds of developing BC than those without (adjusted odds ratio [aOR] 1.47, 95% CI 1.13-1.91). Biopsy-confirmed BBD was associated with BC (aOR 2.25, 95% CI 1.26-4.02). BBD did not significantly mediate the effects of any of the selected BC risk factors.

CONCLUSIONS

In this study, BBD was associated with BC and did not significantly mediate the effects of selected BC risk factors.

Benign breast disease and breast cancer risk in African women: A case-control study

Purpose

To examine the association between benign breast disease (BBD) and breast cancer (BC) in a heterogeneous population of African women.

Methods

BC cases and matched controls were enrolled in three sub-Saharan African countries, Nigeria Cameroon, and Uganda, between 1998-2018. Multivariable logistic regression was used to test the association between BBD and BC. Risk factors dually associated with BBD and BC were selected. Using a parametric mediation analysis model, we assessed if selected BC risk factors were mediated by BBD.

Results

Of 6418 participants, 55.7% (3572) were breast cancer cases. 360 (5.7%) self-reported BBD. Fibroadenoma (46.8%) was the most reported BBD. Women with a self-reported history of BBD had greater odds of developing BC than those without (adjusted odds ratio [aOR] = 1.47, 95% CI: 1.13-1.91). Biopsy-confirmed BBD was associated with BC (aOR = 3.11, 95% CI: 1.78-5.44). BBD did not significantly mediate the effects of any of the selected BC risk factors.

Conclusions

In this study, BBD was associated with BC and did not significantly mediate the effects of selected BC risk factors.

"I haven't had that information, even though I think I'm really well-informed about most things": a qualitative focus group study on Australian women's understanding and views of potentially modifiable risk factors for breast cancer

BACKGROUND

Building health literacy about potentially modifiable risk factors for breast cancer may help to empower women to make more informed decisions about their breast health; however there has been limited qualitative research on this topic. This study aimed to explore current knowledge, understanding and experience of potentially modifiable risk factors for breast cancer, and views on current and future communication strategies for this information and related interventions.

METHODS

Qualitative study using online focus groups via Zoom in October-November 2022. A diverse sample of women from the Australian community aged 40-74 years were recruited.

RESULTS

Fifty-one women from a range of socioeconomic backgrounds took part in nine focus groups. General knowledge of risk factors for breast cancer in the community is limited, particularly in relation to modifiable factors such as alcohol consumption and postmenopausal obesity, with many women describing feelings of 'shock' following this information. Women overwhelming believed that information on modifiable risk factors for breast cancer should be communicated more widely, however communication preferences for receiving this information varied. There was a strong preference amongst the women for a cascade of information which they believed may then help target greater number of women of all ages and backgrounds. Despite worry about long-term compliance, women also supported various lifestyle interventions which may help them and other women to reduce their overall risk.

CONCLUSIONS

Findings from this study highlight the need for more widespread community communication and education about risk factors for breast, in particular potentially modifiable risk factors such as alcohol consumption and postmenopausal obesity. As breast screening programs in Australia and globally begin to evaluate the potential for risk-related screening this will provide an additional context for primary prevention, hence planning of messaging and piloting of lifestyle-related prevention strategies in breast cancer is needed now. Gaining an understanding of women's preferences for communication and forms of interventions is vital to ensure their engagement.

Investigating the Link between Early Life and Breast Anomalies

Several factors during childhood and adolescence are thought to be associated with the development of proliferative benign breast diseases and breast cancer in adulthood. In order to identify them, the authors conducted an extensive review of the literature up to October 2022, searching for clinical studies, reports, and guidelines in English. A thorough Medline/Pubmed and Google scholar database research was performed, investigating the link between diet, exercise, age of menarche, body mass index, ionizing radiation exposure during childhood and adolescence, and proliferative breast diseases and breast cancer in adulthood. A list of keywords, including breast disorders, adolescence, childhood, and breast cancer was included in our search algorithm. Numerous studies concede that the development of breast disease in adulthood is influenced by various risk factors, whose influence begins during early childhood and adolescence.

Alcohol, smoke, cannabis, new psychoactive substances, and non-prescribed drugs consumption among school student in an area of Nord-West of Italy

BACKGROUND

Alcohol and/or substance use disorders are known to be a significant phenomenon in the Western world. The aim of the present study was to evaluate the consumption of alcohol, cigarette smoking, cannabis, new psychoactive substances (NSP) / non prescribed drug (NPD) in a student population in the north-west of Italy (metropolitan area of Genoa).

METHODS

Fourteen comprehensive schools in the metropolitan area of Genoa (Italy) have requested to participate in the education for correct lifestyles meetings (from December 16, 2021, to May 30, 2022). Before each meeting, a meeting was held with the reference teachers: 3805 students aged 9 to 17 were involved. The group was divided by age group: 9-11, 12-13, 14-15 and 16-17 years. Before the lesson, the students were given a questionnaire relating to various topics related to lifestyle or resulting from an incorrect lifestyle (alcohol consumption, cigarette smoking, cannabis, NPS/NPD, psychological path). The questionnaire was anonymous and was approved by the teachers in the preparation phase of the meeting.

RESULTS

Logistic regression analysis found that cannabis use in the age of 14-15 increases the risk of consuming NPD/NPD by more than 26 times (odd ratio 26.3012; 95% CI 15.9656 to 43.3275; P<0.0001). In the age of 16-17, this risk increases approximately 14 times (odd ratio 14.0625; 95% CI 6.1729 to 32.0360; P<0.0001). In the age of 14-15 years, cannabis consumption, alcohol consumption >2 alcoholic units (AUs) on one occasion, NPD increases the probability of the need for a psychological path (cannabis: odds ratio 14.0254, 95% CI 10.9-17.9, P<0.0001; alcohol: odds ratio 3.68, 95% CI 3-4.4, P<0.0001; NPS/NPD: odds ratio 20.98, 16.4-38.4, P<0.0001). In the age of 14-15 and 16-17 years, respectively, 53% (95% CI 50-58%) and 68% (95% CI 66-71%) of students declared that they had neither the parents nor the psychologist of having used alcohol and/or substances.

CONCLUSIONS

These data should be useful to policy makers to implement prevention and health promotion policies through teaching (education for correct lifestyles) to be permanently included in school programs and to be recognized in the curricular path.

Health behaviors in adolescent survivors of cancer: An integrative review

PROBLEM

Adolescent survivors of cancer face an increased risk of chronic health conditions that can be improved by healthy behaviors. The purpose of this review is to synthesize the extent/prevalence of health behaviors (physical activity [PA], diet, human papillomavirus [HPV] vaccination, alcohol use, smoking, marijuana use, and unprotected sex) compared to age-matched peers and factors associated with those behaviors.

ELIGIBILITY CRITERIA

Four databases (PubMed, EMBASE, PsycINFO, and CINAHL) were searched for peer-reviewed primary studies published since 2000 including adolescents aged 11-20 years-old, who had completed cancer treatments. Studies reporting at least one behavior were included.

SAMPLE

Of 1979 articles reviewed, 27 studies reporting any of the following health behaviors were included: PA, diet, HPV vaccination, alcohol use, smoking, marijuana use, or unprotected sex.

RESULTS

Adolescent survivors of cancer engaged less in health risk behaviors (alcohol use, smoking, marijuana use, and unprotected sex) or health-promoting behaviors (PA, healthy diet, and HPV vaccination) compared to age-matched peers. Their health behaviors were associated with psychosocial factors including emotional discomfort (e.g., feeling depressed or nervous) and influence of others (family, friends, and healthcare providers).

CONCLUSIONS

Although health risk behaviors in adolescent survivors of cancer are not as prevalent as in their peers, the survivors' low engagement in health-promoting behaviors including PA, diet, and HPV vaccination is concerning.

IMPLICATIONS

More research is needed to develop and evaluate interventions to improve health-promoting behaviors in adolescent survivors of cancer by strengthening or facilitating psychosocial resources.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Epidemiological characteristics and forecasting incidence for patients with breast cancer in Shantou, Southern China: 2006-2017

This study aimed to explore the epidemiological characteristics of breast cancer and establish an Exponential Smoothing (ETS) and Autoregressive Integrated Moving Average (ARIMA) models to predict the development of incidence in Shantou. This study has a large sample size, strong representativeness, and wide-ranging and comprehensive medical insurance information, which can fill the gaps in basic epidemiological research on breast cancer in Shantou. Successful completion of this study is a helpful tool to understand the epidemiology of Guangdong Province and Southern China. This study also provides data and scientific references for the government and future research on breast cancer prevention and control. This retrospective study was conducted to describe the epidemic intensity, epidemic distribution, and epidemic trend of breast cancer in Shantou, Guangdong Province, from 2006 to 2017, gathered from the Shantou's Medical Security Bureau covers the whole districts of Shantou. ETS and ARIMA models were used to describe the regional distribution, time distribution, and population distribution of breast cancer in Shantou. Moreover, based on the ARIMA model and ETS model, the incidence trend of breast cancer was predicted during 2018-2022. This study included 5,681 breast cancer patients, majority of whom were aged 50-59 years. The male-to-female ratio of the breast cancer patients was about 1:107 (the same ratio of the insured population was 1:1). Female patients accounted for 98.61% of the total insured population. The incidence and mortality rates of female breast cancer were 16.42/100,000 and 0.66/100,000, respectively. Based on the ARIMA model or ARIMA and ETS model, a gradually decreasing trend in the incidence of breast cancer is expected in the future. Comparing the performances of the ARIMA model and ETS model, ARIMA (4, 0, 1) (0, 1, 0) model had a lower the root mean squared error and the mean absolute percentage error than ETS (M, N) model. This population-based retrospective study showed that the high-risk age for the age-specific incidence of female breast cancer was 50-55 years. It is recommended that healthcare administration should strengthen program awareness and education regarding breast cancer prevention and control. It is also possible that feasibility of extrapolating the current methodology to other future studies or broader populations in which the cancer registry data are not available.

Effects of major lifestyle factors on breast cancer risk: impact of weight, nutrition, physical activity, alcohol and tobacco

Breast cancer (BC) is the most commonly diagnosed cancer and second most common cause of cancer death in US women. Family history and genetics are well-known BC risk factors, but they only account for 15–20% of BC cases. Therefore, in addition to family history, healthcare providers must consider a woman’s modifiable and nonmodifiable personal risk factors that are associated with an increase in BC risk. The World Cancer Research Fund/American Institute for Cancer Research estimate that 30% of BC cases in the US are preventable. Lifestyle education is imperative given the magnitude of BC occurrence. Evidence supports prevention as an effective, long-term strategy for reducing risk. Healthcare providers are key stakeholders in empowering patients to adopt a healthy lifestyle for primary BC prevention. In this paper, we review the available evidence on modifiable BC risk including weight management, nutrition, physical activity, alcohol and tobacco use and provide strategies to counsel patients on lifestyle modifications.

Adolescent alcohol, nuts, and fiber: combined effects on benign breast disease risk in young women

Adolescent drinking is associated with higher risks of proliferative benign breast disease (BBD) and invasive breast cancer (BC). Furthermore, adolescent nut and fiber consumptions are associated with lower risks of benign lesions and premenopausal BC. We hypothesize that diet (nuts, fiber) may mitigate the elevated BBD risk associated with alcohol. A prospective cohort of 9031 females, 9-15 years at baseline, completed questionnaires in 1996-2001, 2003, 2005, 2007, 2010, 2013, and 2014. Participants completed food frequency questionnaires in 1996-2001. In 2005, participants (>=18 years) began reporting biopsy-confirmed BBD (N = 173 cases). Multivariable logistic regression estimated associations between BBD and cross-classified intakes (14-17 years) of alcohol and peanut butter/nuts (separately, total dietary fiber). Only 19% of participants drank in high school; drinking was associated with elevated BBD risk (OR = 1.75, 95% CI: 1.20-2.56; p = 0.004) compared to nondrinkers. Participants consuming any nuts/butter had lower BBD risk (OR = 0.64, 95% CI: 0.45-0.90; p = 0.01) compared to those consuming none. Participants in top 75% fiber intake had lower risk (OR = 0.57, 95% CI: 0.40-0.81; p = 0.002) compared to bottom quartile. Testing our hypothesis that consuming nuts/butter mitigates the elevated alcohol risk, analyzing alcohol and nuts combined found that those who consumed both had lower risk (RR = 0.47, 95% CI: 0.24-0.89; p = 0.02) compared to drinkers eating no nuts. Our analysis of alcohol and fiber together did not demonstrate risk mitigation by fiber. For high school females who drink, their BBD risk may be attenuated by consuming nuts. Due to modest numbers, future studies need to replicate our findings in adolescent/adult females. However, high school students may be encouraged to eat nuts and fiber, and to avoid alcohol, to reduce risk of BBD and for general health benefits.

Alcohol's Effects on Breast Cancer in Women

Globally, more than 2 million new cases of breast cancer are reported annually. The United States alone has more than 496,000 new cases every year. The worldwide prevalence is approximately 6.8 million cases. Although many risk factors for breast cancer are not modifiable, understanding the role of the factors that can be altered is critical. Alcohol consumption is a modifiable factor. Studies of alcohol in relation to breast cancer incidence have included hundreds of thousands of women. Evidence is consistent that intake, even intake of less than 10–15 grams per day, is associated with increased risk of this disease. In addition, evidence, although less extensive, shows that possible early indicators of risk, such as benign breast disease and increased breast density, are associated with alcohol consumption. Evidence is less strong for differences based on geographic region, beverage type, drinking pattern, or breast cancer subtype. Some studies have examined the association between alcohol and recurrence or survival after a breast cancer diagnosis. These findings are less consistent. Public awareness of alcohol as a risk factor for breast cancer is low, and public health measures to increase that awareness are warranted.

Dietary intake from birth through adolescence in relation to risk of benign breast disease in young women

PURPOSE

Nutritional factors during different periods in life impact breast cancer risk. Because benign breast disease (BBD) is a well-established risk factor for breast cancer, we investigated childhood nutrition from birth through age 14 year and subsequent BBD.

METHODS

A prospective cohort study of 9031 females, 9-15 year at baseline, completed questionnaires (including heights, weights) annually from 1996 to 2001, in 2003, 2005, 2007, 2010, 2013 and 2014. In 1996, mothers reported infant feeding practices during their daughters first year of life. Beginning in 1996, participants completed annual food frequency questionnaires. In 2005, participants (18 year +) began reporting whether they had ever been diagnosed with biopsy-confirmed BBD (N = 173 cases). Multivariable logistic regression models estimated associations between childhood nutrition and BBD, adjusted for maternal breast disease and childhood body size factors.

RESULTS

Although no infant nutrition factors were associated with biopsy-confirmed BBD, certain adolescent dietary factors were. A multivariable model simultaneously included the most important diet and body size factors from different age periods: higher BBD risk was associated with greater age 10 year consumption of animal (non-dairy, energy-adjusted) fat (OR 2.27, p < .02, top vs. bottom quartiles) and with lower 14 year consumption of nuts/peanut butter (OR 0.60, p = .033, top vs. bottom quartiles).

CONCLUSION

Greater intake of animal (non-dairy) fat at 10 year and lower intake of nuts/peanut butter at 14 year were independently associated with higher BBD risk. These dietary factors appeared to operate on BBD risk independent of childhood growth (gestational weight gain, childhood BMI and height, adolescent height growth velocity), young adult height and BMI, and family history.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Physical activity, sedentary behaviour, diet, and cancer: an update and emerging new evidence

The lifestyle factors of physical activity, sedentary behaviour, and diet are increasingly being studied for their associations with cancer. Physical activity is inversely associated with and sedentary behaviour is positively (and independently) associated with an increased risk of more than ten types of cancer, including colorectal cancer (and advanced adenomas), endometrial cancers, and breast cancer. The most consistent dietary risk factor for premalignant and invasive breast cancer is alcohol, whether consumed during early or late adult life, even at low levels. Epidemiological studies show that the inclusion of wholegrain, fibre, fruits, and vegetables within diets are associated with reduced cancer risk, with diet during early life (age <8 years) having the strongest apparent association with cancer incidence. However, randomised controlled trials of diet-related factors have not yet shown any conclusive associations between diet and cancer incidence. Obesity is a key contributory factor associated with cancer risk and mortality, including in dose-response associations in endometrial and post-menopausal breast cancer, and in degree and duration of fatty liver disease-related hepatocellular carcinoma. Obesity produces an inflammatory state, characterised by macrophages clustered around enlarged hypertrophied, dead, and dying adipocytes, forming crown-like structures. Increased concentrations of aromatase and interleukin 6 in inflamed breast tissue and an increased number of macrophages, compared with healthy tissue, are also observed in women with normal body mass index, suggesting a metabolic obesity state. Emerging randomised controlled trials of physical activity and dietary factors and mechanistic studies of immunity, inflammation, extracellular matrix mechanics, epigenetic or transcriptional regulation, protein translation, circadian disruption, and interactions of the multibiome with lifestyle factors will be crucial to advance this field.

Combined Patterns of Risk for Problem and Obesogenic Behaviors in Adolescents: A Latent Class Analysis Approach

BACKGROUND

Several studies have used latent class analyses to explore obesogenic behaviors and substance use in adolescents independently. We explored a variety of health risks jointly to identify distinct patterns of risk behaviors among adolescents.

METHODS

Latent class models were estimated using Youth Risk Behavior Surveillance System (YRBSS) 2011 data. Behaviors in the models included substance use, physical fights, physical activity (PA), sedentary activity, sleep, fruit and vegetables (F&V) consumption, and weight-related variables. Models were estimated separately by sex. Constrained and unconstrained models were computed for race. Age and perceived and calculated weight status were compared among emergent latent classes using latent multinomial logistic regressions.

RESULTS

Four and 5 latent class solutions emerged for boys and girls, respectively. Healthy, sedentary, and physically active (PA) groups were common in both boys and girls. The sample of boys also included a health risk behavior (HRB)/PA group and the sample of girls included HRB and HRB/F&V groups.

CONCLUSIONS

The results confirm that obesogenic and HRBs should be conceptualized as combined patterns of risk. Health education programming in schools should adopt a multiple health behavior approach to target the continuum of risks adolescents engage in simultaneously.

European Code against Cancer 4th Edition: Alcohol drinking and cancer

Alcohol consumption is the third leading risk factor for disease and mortality in Europe. As evaluated by the International Agency for Research on Cancer (IARC) Monographs, a causal relationship is established for consumption of alcoholic beverages and cancers of the oral cavity, pharynx, larynx, oesophagus, liver, colorectum and female breast, even at low and moderate alcohol intakes. The higher the amount of alcohol consumed, the higher the risk of developing cancer. In Europe, an estimated 10% (95% CI: 7%-13%) of all cancer cases in men and 3% (95% CI: 1%-5%) of all cancer cases in women are attributable to alcohol consumption. Several biological mechanisms explain the carcinogenicity of alcohol; among them, ethanol and its genotoxic metabolite, acetaldehyde, play a major role. Taking all this evidence into account, a recommendation of the 4th edition of European Code against Cancer is: "If you drink alcohol of any type, limit your intake. Not drinking alcohol is better for cancer prevention."

Breast Cancer Research in the Nurses' Health Studies: Exposures Across the Life Course

OBJECTIVES

To review the contribution of the Nurses' Heath Study (NHS) and the NHS II in identifying risk and protective factors for breast cancer incidence and survival.

METHODS

We conducted a narrative review of NHS and NHS II articles on breast cancer incidence and survival published from 1976 to 2016, with a focus on exogenous and endogenous hormones; lifestyle factors, including diet, physical activity, and aspirin use; intermediate markers of risk; and genetic factors.

RESULTS

With the investigation of individual risk factors, as well as their incorporation into risk prediction models, the NHS has contributed to the identification of ways in which women may reduce breast cancer risk, including limiting alcohol consumption, reducing the duration of postmenopausal estrogen-plus-progestin use, avoiding weight gain, and increasing vegetable consumption. In addition, the NHS has helped elucidate the roles of several biomarkers and contributed to the identification of risk alleles.

CONCLUSIONS

The NHS has contributed to our understanding of lifestyle, hormonal, and genetic risk factors for breast cancer, highlighting the importance of exposures across the life course, and has helped identify lifestyle changes that may reduce risk and improve survival after a diagnosis of breast cancer.

Is breast cancer risk associated with alcohol intake before first full-term pregnancy?

PURPOSE

It is plausible that breast tissue is particularly susceptible to carcinogens, including ethanol, between menarche and the first full-term pregnancy ("first pregnancy"). There is some epidemiological evidence that intake before the first pregnancy is more closely associated with risk of breast cancer than is intake thereafter. We examined this association using lifetime alcohol consumption data from a prospective cohort study.

METHODS

We calculated usual alcohol intake for age periods 15-19 years and for 10-year period from age 20 to current age (in grams per day) using recalled frequency and quantity of beverage-specific consumption for 13,630 parous women who had their first pregnancy at age 20 years or later, had no cancer history and were aged 40-69 years at enrollment. Cox regression was performed to estimate hazard ratios (HRs) and their 95 % confidence intervals (CIs).

RESULTS

A total of 651 incident invasive adenocarcinomas of the breast were diagnosed during a mean follow-up of 16.1 years. Alcohol consumption was low overall with only a few drinking ≥40 g/day. Intake before the first pregnancy was markedly lower (mean intake: 2.5 g/day; abstention: 58.8 %) than intake thereafter (mean intake: 6.0 g/day; abstention: 33.6 %). Any alcohol intake before the first pregnancy was associated with an increased risk of breast cancer (HR 1.35, 95 % CI 1.10-1.66 for drinking compared with abstention), whereas any intake after the first pregnancy was not (HR 0.89, 95 % CI 0.72-1.09).

CONCLUSIONS

Limiting alcohol intake before the first pregnancy might reduce women's risk of breast cancer.

European Code against Cancer 4th Edition: Alcohol drinking and cancer

Alcohol consumption is the third leading risk factor for disease and mortality in Europe. The International Agency for Research on Cancer (IARC) Monographs provide strengthened evidence that the consumption of alcoholic beverages is causally associated with cancers of the oral cavity, pharynx, larynx, oesophagus, liver, colorectum and female breast, even for low and moderate alcohol intakes. The risk of cancer increases in a dose-dependent manner, and the higher the amount of alcohol consumed, the higher the risk of developing cancer. Several biological mechanisms explain the carcinogenicity of alcohol; among them, ethanol and its genotoxic metabolite acetaldehyde play a major role. Taking all this evidence into account, a recommendation of the 4th edition of the European Code against Cancer (ECAC) is: "If you drink alcohol of any type, limit your intake. Not drinking alcohol is better for cancer prevention."

Alcohol intake and breast cancer in the European prospective investigation into cancer and nutrition

Alcohol intake has been associated to breast cancer in pre and postmenopausal women; however results are inconclusive regarding tumor hormonal receptor status, and potential modifying factors like age at start drinking. Therefore, we investigated the relation between alcohol intake and the risk of breast cancer using prospective observational data from the European Prospective Investigation into Cancer and Nutrition (EPIC). Up to 334,850 women, aged 35-70 years at baseline, were recruited in ten European countries and followed up an average of 11 years. Alcohol intake at baseline and average lifetime alcohol intake were calculated from country-specific dietary and lifestyle questionnaires. The study outcomes were the Hazard ratios (HR) of developing breast cancer according to hormonal receptor status. During 3,670,439 person-years, 11,576 incident breast cancer cases were diagnosed. Alcohol intake was significantly related to breast cancer risk, for each 10 g/day increase in alcohol intake the HR increased by 4.2% (95% CI: 2.7-5.8%). Taking 0 to 5 g/day as reference, alcohol intake of >5 to 15 g/day was related to a 5.9% increase in breast cancer risk (95% CI: 1-11%). Significant increasing trends were observed between alcohol intake and ER+/PR+, ER-/PR-, HER2- and ER-/PR-HER2- tumors. Breast cancer risk was stronger among women who started drinking prior to first full-time pregnancy. Overall, our results confirm the association between alcohol intake and both hormone receptor positive and hormone receptor negative breast tumors, suggesting that timing of exposure to alcohol drinking may affect the risk. Therefore, women should be advised to control their alcohol consumption.

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.

The relationship between exposure to alcohol-related content on Facebook and predictors of alcohol consumption among female emerging adults

Consuming an unhealthy level of alcohol is a significant problem for some young women. Potential determinants of excess consumption include perceptions of usual consumption among peers-perceptions of what is "normal." The present study examined whether perceptions of social normative endorsement of drinking, operationalized by measures of perceived alcohol consumption of close friends (proximal norms), the consumption of the "average student" (distal norms), and the extent of alcohol-related content posted by peers on Facebook were related to alcohol-related attitudes and self-reported consumption. Female university students (n=129; Mage=21.48 years, SD=3.00) completed an online questionnaire assessing Facebook use, perceived alcohol-related norms, and self-reported alcohol attitudes and consumption. Perceptions of the consumption of the average female student were a negative predictor of attitudes. Positive alcohol attitudes, extent of own alcohol-related photographic posts on Facebook, average female student alcohol consumption, and report of male close friend consumption predicted self-report of own alcohol consumption. Interestingly, female close friend norms failed to predict consumption, whereas male close friend norms predicted consumption but not attitudes, suggesting the possibility of separate cognitive pathways for alcohol-related attitudes and behavior. This study builds on existing research by casting new light on predictors of alcohol-related attitudes, as well as describing the potential role of social networking sites such as Facebook in the formation of social norms and the modulation of drinking behavior.

Breast cancer risk associated with benign breast disease: systematic review and meta-analysis

Benign breast disease (BBD) is a broad category of diagnoses reported to convey a variable degree of increased risk of developing breast cancer. A meta-analysis of the existing literature was performed to quantify the risk estimate associated with BBD. Pubmed, Google Scholar, and EMBASE databases were searched in January 2011. English retrospective and prospective observational studies published from 1972 to 2010 evaluating BBD and the risk of breast cancer were included with data acquisition reported from 1930 to 2007. Eligibility was performed independently following a standardized protocol for full-text publication review by a single reviewer and reviewed by a second author. Of the 3,409 articles retrieved from the literature search, 32 studies met the selection criteria. Reported risk estimates, including relative risk, odds ratio, standardized incidence ratios, rate ratio, hazards ratio, and incidence rate ratio, were the primary outcomes extracted. The most commonly reported pathologies were decided prior to extraction and organized into the following categories for analysis of the extracted risk estimate: non-proliferative disease (NPD), proliferative disease without atypia, benign breast disease not otherwise specified (BBD), and atypical hyperplasia not otherwise specified (AHNOS). The mean age at benign breast biopsy was 46.1 years and the mean age of developing breast cancer was 55.9 years. The mean follow-up length was 12.8 years (range 3.3-20.6). The summary risk estimate of developing breast cancer for NPD was 1.17 (N = 8; 95% CI 0.94-1.47). Proliferative disease without atypia was associated with significantly increased risk of future breast cancer, summary relative risk 1.76 (N = 15; 95% CI 1.58-1.95). The summary risk estimate for AHNOS was 3.93 (N = 13; 95% CI 3.24-4.76). This meta-analysis demonstrates that proliferative benign breast disease with or without atypia is associated with a significant increase in risk of developing breast cancer. These data support management strategies for women with benign breast disease such as additional screening methods or chemoprevention.

Differences among college women for breast cancer prevention acquired information-seeking, desired apps and texts, and daughter-initiated information to mothers

The purpose of this study was to examine among college women acquired breast cancer prevention information-seeking, desired apps and texts, and information given to mothers. Using a cross-sectional study, a survey was administered to college women at a southwestern university. College women (n = 546) used the Internet (44 %) for active breast cancer prevention information-seeking and used the Internet (74 %), magazines (69 %), and television (59 %) for passive information receipt. Over half of the participants desired breast cancer prevention apps (54 %) and texts (51 %). Logistic regression analyses revealed predictors for interest to receive apps were ethnicity (Hispanic), lower self-efficacy, actively seeking online information, and older age and predictors for interest to receive texts were lower self-efficacy and higher university level. Eighteen percent of college women (n = 99) reported giving information to mothers and reported in an open-ended item the types of information given to mothers. Predictors for giving information to mothers were actively and passively seeking online information, breast self-exam practice, and higher university level. Screenings were the most frequent types of information given to mothers. Breast cancer prevention information using apps, texts, or Internet and daughter-initiated information for mothers should be considered in health promotion targeting college students or young women in communities. Future research is needed to examine the quality of apps, texts, and online information and cultural differences for breast cancer prevention sources.

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.

Adolescent physical activity and inactivity: a prospective study of risk of benign breast disease in young women

In previous investigations of adolescent activity recalled in adulthood, modest reductions in risk of benign breast disease (BBD) and premenopausal breast cancer were seen with moderate-strenuous activity during high school. We therefore investigated physical activity, walking, and recreational inactivity (watching TV-videos, playing computer-videogames) reported by adolescent girls in relation to their subsequent risk for BBD as young women. The Growing Up Today Study includes 9,039 females, 9-15 years at study initiation (1996), who completed questionnaires annually through 2001, then in 2003, 2005, 2007, 2010 and 2013. Annual surveys (1996-2001) obtained data on physical and sedentary activities during the past year. Beginning in 2005, women (≥18 years) reported whether they had ever been diagnosed with BBD confirmed by breast biopsy (n = 133 cases, to 11/01/2013). Logistic regression (adjusted for baseline adiposity and age; additional factors in multivariable-adjusted models) estimated associations between adolescent activities (moderate-vigorous, walking, METS, inactivity) and biopsy-confirmed BBD in young women. Girls who walked the most had significantly lower risk of BBD (multivariable-adjusted OR = 0.61, ≥30 vs ≤15 min/day; p = .049). We observed no evidence that inactivity (≥3 vs <2 h/day OR = 1.02, p = .92) or METS (top vs bottom tertile OR = 1.19, p = .42) were associated with BBD. Accounting for factors including family history, childhood adiposity, and other activities and inactivities, adolescent girls who walked the most were at lower risk for BBD. We found no evidence that high moderate-vigorous activity might reduce risk, nor did we observe any association with inactivity. Continued follow-up will re-evaluate these findings as more BBD cases, and ultimately breast cancer, are diagnosed.

Breast cancer risk accumulation starts early: prevention must also

Nearly one in four breast cancers is diagnosed before the age of 50, and many early-stage premalignant lesions are present but not yet diagnosed. Therefore, we review evidence to support the strategy that breast cancer prevention efforts must begin early in life. This study follows the literature review methods and format. Exposures during childhood and adolescence affect a woman's long-term risk of breast cancer, but have received far less research attention than exposures that occur later in life. Breast tissue undergoes rapid cellular proliferation between menarche and first full-term pregnancy, and risk accumulates rapidly until the terminal differentiation that accompanies first pregnancy. Evidence on childhood diet and growth in height, and adolescent alcohol intake, among other adolescent factors is related to breast cancer risk and risk of premalignant proliferative benign lesions. Breast cancer prevention efforts will have the greatest effect when initiated at an early age and continued over a lifetime. Gaps in knowledge are identified and deserve increase attention to inform prevention.

Adolescent carotenoid intake and benign breast disease

BACKGROUND

Carotenoids may reduce risk of benign breast disease (BBD), an independent risk factor for breast cancer, through antioxidative or antiproliferative mechanisms. Exposure to carotenoids may be most important during adolescence when breast tissue is still developing. We examined adolescent carotenoid intake in relation to BBD in young women.

METHODS

In 6593 adolescent girls in the prospective Growing Up Today Study cohort, intakes of α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and lycopene were assessed by using the means from food-frequency questionnaires in 1996, 1997, and 1998. Girls reported biopsy-confirmed BBD on questionnaires in 2005, 2007, and 2010 (n = 122). We conducted logistic regression of energy-adjusted carotenoid intakes in relation to BBD, adjusted for age, family history of breast cancer or BBD, age at menarche, nulliparity, alcohol intake, BMI, and physical activity.

RESULTS

Mean (SD) age at baseline was 12.0 (1.6) years. β-Carotene intake was inversely associated with BBD; comparing the highest to lowest quartile, the multivariate-adjusted odds ratio was 0.58 (95% confidence interval: 0.34-1.00; P-trend = .03). α-Carotene and lutein/zeaxanthin were also inversely associated with BBD, but the associations were not statistically significant.

CONCLUSIONS

Adolescent carotenoid intake may be associated with lower BBD risk; these findings warrant further study.

Recent evidence on alcohol and cancer epidemiology

This review presents an overview of the impact of alcohol consumption on cancer risk. Results from the 2009 International Agency for Research on Cancer monograph as well as the most recent meta-analyses and epidemiological studies are considered. Alcohol consumption is one of the most important known risk factors for human cancer and potentially one of the most avoidable factors, but it is increasing worldwide. Ethanol in alcoholic beverages is carcinogenic to humans and causes several cancers (oral cavity, pharynx, larynx, esophagus, colorectum, liver and female breast). Cumulative lifetime consumption, frequency and drinking pattern appear to play a role in risk characterization. While the role of heavy drinking has been long recognized, new evidence suggests that light consumption (up to one drink/day) is also associated with adverse effects. In addition, some genetic polymorphisms interact with alcohol metabolism and may modify its impact.

Female breast cancer and alcohol consumption: a review of the literature

CONTEXT

Consumption of alcoholic beverages is one of the single most important known and modifiable risk factor for human cancer. Among women, breast cancer is the most common cancer worldwide and the leading cause of cancer-related mortality. Consumption of alcoholic beverages is causally associated with female breast cancer and the association shows a linear dose-response relationship. The role of heavy drinking has been long recognized and even a moderate intake is associated with an increased risk for breast cancer. The present review is an update of the current evidence on the association between alcohol consumption and breast cancer risk. The aim is to gain further insight into this association and to improve our current understanding of the effects of the major modifying factors.

EVIDENCE ACQUISITION

Epidemiologic and experimental studies published since the most recent International Agency for Research on Cancer (IARC) Monograph on alcoholic beverages were identified in PubMed using a combination of keywords such as alcohol, breast cancer, polymorphisms, menopausal status.

EVIDENCE SYNTHESIS

Cumulative lifetime consumption, drinking frequency, drinking patterns and timing of exposure each modulate the association between alcohol consumption and breast cancer. Hormonal status, genetic polymorphisms, and nutritional factors may interact with ethanol metabolism and further influence breast cancer risk.

CONCLUSIONS

Better standardization among experimental and epidemiologic designs in assessing alcohol intake and timing of exposure may improve our understanding of the heterogeneity observed across studies, possibly allowing the quantification of the effects of occasional heavy drinking and the identification of a window of higher susceptibility to breast cancer development.

Alcohol intake between menarche and first pregnancy: a prospective study of breast cancer risk

BACKGROUND

Adult alcohol consumption during the previous year is related to breast cancer risk. Breast tissue is particularly susceptible to carcinogens between menarche and first full-term pregnancy. No study has characterized the contribution of alcohol consumption during this interval to risks of proliferative benign breast disease (BBD) and breast cancer.

METHODS

We used data from 91,005 parous women in the Nurses' Health Study II who had no cancer history, completed questions on early alcohol consumption in 1989, and were followed through June 30, 2009, to analyze breast cancer risk. A subset of 60,093 women who had no history of BBD or cancer in 1991 and were followed through June 30, 2001, were included in the analysis of proliferative BBD. Relative risks (RRs) were estimated using Cox proportional hazard regression.

RESULTS

We identified 1609 breast cancer cases and 970 proliferative BBD cases confirmed by central histology review. Alcohol consumption between menarche and first pregnancy, adjusted for drinking after first pregnancy, was associated with risks of breast cancer (RR = 1.11 per 10 g/day intake; 95% confidence interval [CI] = 1.00 to 1.23) and proliferative BBD (RR = 1.16 per 10 g/day intake; 95% CI = 1.02 to 1.32). Drinking after first pregnancy had a similar risk for breast cancer (RR = 1.09 per 10 g/day intake; 95% CI = 0.96 to 1.23) but not for BBD. The association between drinking before first pregnancy and breast neoplasia appeared to be stronger with longer menarche to first pregnancy intervals.

CONCLUSIONS

Alcohol consumption before first pregnancy was consistently associated with increased risks of proliferative BBD and breast cancer.

Vegetable protein and vegetable fat intakes in pre-adolescent and adolescent girls, and risk for benign breast disease in young women

Previous investigations, of adolescent diet recalled in adulthood, found lower risk for benign breast disease (BBD) with higher intakes of vegetable fat and nuts during high school. We investigate whether vegetable protein and fat, derived from diets reported during pre-adolescence and adolescence, are associated with subsequent risk for BBD in young women. The Growing Up Today Study includes 9,039 females, 9-15 years in 1996, who completed questionnaires annually through 2001, and then in 2003, 2005, 2007, and 2010. Food frequency questionnaires (1996-2001) obtained intake data on a variety of foods. Beginning in 2005, women (18-30 years) reported whether they had ever been diagnosed with BBD that was confirmed by breast biopsy (n = 112 cases). Logistic regression estimated associations between intakes of vegetable protein and fat and biopsy-confirmed BBD. Those individual foods that were the largest contributors of protein and fat in this cohort were also investigated. In analyses of intakes from 1996 through 1998, when our cohort was youngest, vegetable fat (OR = 0.72/(10 gm/day), 95 % CI 0.53-0.98; p = 0.04) was inversely associated with BBD risk. The greatest sources of vegetable fat and protein in these girls were peanut butter, peanuts, nuts, beans (beans, lentils, and soybeans), and corn. A daily serving of any one of these was associated with lower risk (OR = 0.32/(serv/day), 95 % CI 0.13-0.79; p = 0.01). Peanut butter (and nuts) at age 11 years was inversely associated with risk (p = 0.01). In analyses of intakes at age 14 years, vegetable protein was associated with lower BBD risk (OR = 0.64/(10 gm/day), 95 % CI 0.43-0.95; p = 0.03). A daily serving at 14 years of any one of the foods was associated with lower risk (OR = 0.34, 95 % CI 0.16-0.75; p = 0.01), as was peanut butter (and nuts) (p = 0.02). Girls with a family history of breast cancer had significantly lower risk if they consumed these foods or vegetable fat. In conclusion, consumption of vegetable protein, fat, peanut butter, or nuts by older girls may help reduce their risk of BBD as young women.

Invited commentary: are dietary intakes and other exposures in childhood and adolescence important for adult cancers?

In this issue of the Journal, Nimptsch et al. (Am J Epidemiol. 2013;178(2):172-183) report significant associations between female adolescents' poultry consumption in high school and subsequent reduced risk of colorectal adenomas in adulthood. Consumption of red meat or fish was not related to risk, but replacement with poultry reduced the risk of later adenomas. Most epidemiologic studies of adult diseases lack exposure data from the distant past. By focusing on a cancer precursor lesion and using a variety of methods to assess data quality, the investigators address concerns about the quality of distant recall. These findings add to the growing evidence that links childhood and adolescent lifestyle and environmental exposures with subsequent risk of cancers arising in adulthood. Highlights of the literature on this topic and methodological challenges are summarized. Future studies would benefit from incorporating measures of lifestyle, diet, environmental exposures, and other risk factors from early in life and from validation and other data quality checks of such measurements. Sources of historical data on children's and adolescents' exposures should be sought and evaluated in conjunction with subsequent exposures in relationship to adult-onset cancers.

Association between diet during preadolescence and adolescence and risk for breast cancer during adulthood

It is increasingly evident that diet during preadolescence and adolescence has important consequences for breast cancer during adulthood. However, only a few epidemiologic studies have been conducted on the relationship between diet during preadolescence and adolescence, and cancer during adulthood. This situation is partly because of methodological challenges such as the long latency period, the complexity of breast cancer, the lack of validated diet assessment tools, and the large number of subjects that must be followed, all of which increase costs. In addition, funding opportunities are few for such studies. Results from the small number of epidemiologic studies are inconsistent, but evidence is emerging that specific aspects of the diet during preadolescence and adolescence are important. For example, during preadolescence and adolescence, severe calorie restriction with poor food quality, high total fat intake, and alcohol intake tend to increase risk, whereas high soy intake decreases risk. Research on preadolescent and adolescent diet is a paradigm shift in breast cancer investigations. This research paradigm has the potential to produce transformative knowledge to inform breast cancer prevention strategies through dietary intervention during preadolescence and adolescence, rather than later in life, as is current practice, when it is perhaps less effective. Methodological challenges that have plagued the field might now be overcome by leveraging several existing large-scale cohort studies in the U.S. and around the world to investigate the role of diet during preadolescence and adolescence in risk for adult breast cancer.

Preadolescent and adolescent risk factors for benign breast disease

PURPOSE

It is well established that exposures during childhood and adolescence affect breast cancer risk much later in life. Recently, studies have begun to evaluate whether early life exposures might also impact the risk of developing benign breast disease (BBD). A diagnosis of proliferative BBD independent of other breast cancer risk factors also increases the subsequent risk of breast cancer; therefore, understanding how to decrease the incidence of BBD may have important implications for primary breast cancer prevention.

METHODS

We reviewed several studies from prospective cohort studies that have investigated the relationship between risk factors during childhood and adolescence, such as anthropometric and reproductive characteristics as well as diet and other behaviors, and subsequent risk of BBD.

RESULTS

Higher intake of vegetable oils, nuts, vitamin E, and fiber and lower consumption of animal fat, red meat, and alcohol are associated with reduced risk of BBD. Childhood weight and adolescent body mass index are inversely associated with BBD risk, whereas a greater peak height velocity during adolescence is associated with a higher risk of BBD. There was no association between age of menarche and risk of BBD.

CONCLUSION

Early life exposures and behaviors appear to impact BBD risk. The current body of evidence further supports the importance of a life-course approach to breast cancer prevention.

Dairy intakes in older girls and risk of benign breast disease in young women

Previous investigations found high dairy intakes in girls associated with rapid height growth and excess weight gain, which had opposite relationships with benign breast disease (BBD) in young women. We use data from the longitudinal Growing Up Today Study (GUTS) to investigate whether dairy intakes, in older children/adolescents, are associated with BBD risk in young women. GUTS includes 9,039 females, ages 9-15 years in 1996, who completed questionnaires annually through 2001, then in 2003, 2005, 2007, and 2010. Dietary food frequencies (1996-2001) obtained milk, yogurt, and cheese intakes. On 2005-2010 surveys, 7,011 females (18-29 years) reported whether a health care provider ever diagnosed them with BBD (n = 250) and if confirmed by breast biopsy (n = 105). Logistic regression models estimated associations between prevalent biopsy-confirmed BBD and dairy intakes, adjusted for age and energy. Multivariable-adjusted models additionally included menarche age, childhood adiposity, adolescent alcohol consumption, and pregnancy. Further analyses stratified by family history. Age-energy-adjusted models of dairy (milk, yogurt, cheese, total dairy servings, dairy protein, dairy fat) intakes at 14 yr found no significant associations with BBD risk [milk: OR, 0.90/(serving/d); 95% confidence interval (CI), 0.76-1.05; dairy protein: OR, 0.98/(10 g/d); 95% CI, 0.82-1.17). Separate analyses of dairy intakes at 10 yr, intakes before the growth spurt, during the growth spurt, before menses-onset, and after menses-onset provided no significant associations with BBD. Multivariable adjustment, and family history stratification, did not alter the above findings. We conclude that dairy intakes by older girls have no strong relation with BBD risk in young women. Because of small number of cases, it is important to continue follow-up and re-examine later.

Prostate cancer: is it time to expand the research focus to early-life exposures?

Although the contribution of lifestyle and environment (non-genetic factors) to prostate carcinogenesis is indicated by international variation in prostate cancer occurrence and migration studies, no conclusive modifiable risk factors have yet been identified. One possible reason for this may be the dearth of epidemiological research on exposures experienced early in life, when the immature prostate may be more susceptible to carcinogenic exposures. In this Opinion article, we summarize the rationale for studying early-life exposures, describe the small body of early-life research and its associated challenges, and point to solutions for future research.

Applying what we know to accelerate cancer prevention

More than half of the cancer occurring today is preventable by applying knowledge that we already have. Tobacco, obesity, and physical inactivity are the modifiable causes of cancer that generate the most disease. Cancer burden can be reduced by alterations in individual and population behaviors and by public health efforts as long as these changes are driven by sound scientific knowledge and social commitment to change. The obstacles to these efforts are societal and arise from the organization of institutions, including academia, and in the habits of daily life. To achieve maximal possible cancer prevention, we will need better ways to implement what we know and improved infrastructure that will better incentivize and support transdisciplinary, multilevel research and successful intervention.

Intakes of alcohol and folate during adolescence and risk of proliferative benign breast disease

OBJECTIVES

To examine the combined effect of alcohol and folate intake during adolescence on the risk of proliferative benign breast disease (BBD).

METHODS

We used data from 29 117 women in the Nurses' Health Study II who completed both adolescent alcohol consumption questions in 1989 and an adolescent diet questionnaire in 1998. A total of 659 women with proliferative BBD diagnosed between 1991 and 2001 were confirmed by central pathology review. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals (CIs), adjusted for established risk factors of breast cancer.

RESULTS

Adolescent alcohol consumption was dose-dependently associated with an increased risk of proliferative BBD (hazard ratio = 1.15 per 10 g/day consumption; 95% CI, 1.03-1.28). There was no significant association between adolescent folate intake and the risk of proliferative BBD. Stratified analyses showed that each 10-g/day alcohol intake during adolescence was associated with a 21% (95% CI, 1.01-1.45) increase in the risk of proliferative BBD among women with low folate intake during adolescence, which was not significantly different from the alcohol-associated risk among women with moderate and high folate intake during adolescence (P for interaction = 0.18).

CONCLUSIONS

Adolescent alcohol consumption is associated with increased risk of proliferative BBD, which may not be reduced by increased folate intake during adolescence.

Challenges and opportunities in research on early-life events/exposures and cancer development later in life

It is becoming increasingly evident that early-life events and exposures have important consequences for cancer development later in life. However, epidemiological studies of early-life factors and cancer development later in life have had significant methodological challenges such as the long latency period, the distinctiveness of each cancer, and large number of subjects that must be studied, all likely to increase costs. These traditional hurdles might be mitigated by leveraging several existing large-scale prospective studies in the United States (US) and globally, as well as birth databases and birth cohorts, in order to launch both association and mechanistic studies of early-life exposures and cancer development later in life. Dedicated research funding will be needed to advance this paradigm shift in cancer research, and it seems justified by its potential to produce transformative understanding of how cancer develops over the life-course. This in turn has the potential to transform cancer prevention strategies through interventions in early-life rather than later in life, as is the current practice, where it is perhaps less effective.

Young women with family history of breast cancer and their risk factors for benign breast disease

BACKGROUND

Breast cancer (BC) patients wonder how their daughters might reduce their risk. The authors investigated childhood/adolescent risk factors for benign breast disease (BBD), a well-documented risk factor for BC, among girls with a family history.

METHODS

GUTS (the Growing Up Today Study) includes females, aged 9 to 15 years in 1996, who completed annual questionnaires during 1996 to 2001, then in 2003, 2005, and 2007. Participants provided information regarding alcohol, menarche, height, and body mass index (BMI; kg/m(2)). Peak height growth velocity (PHV; in./y) was estimated from longitudinal heights. On 2005-2007 surveys, 6888 women (18-27 years old) reported whether they were diagnosed with biopsy-confirmed BBD (n = 67 cases); 6741 women (noncases) reported no BBD. Participants' mothers reported their own biopsy-confirmed BBD and BC, and BC in their sisters and mothers. Stratified by family history, logistic models investigated BBD risk factors.

RESULTS

Young women whose mothers or aunts had BC were more likely to be diagnosed with BBD (odds ratio [OR], 2.34; P = .01), as were those with maternal BBD (OR, 1.59; P = .095). Adolescents with BC family history (mother, aunt, grandmother) who consumed alcohol (7 drinks/wk) doubled their BBD risk (OR, 2.28; P = .01), similar to those with maternal BBD (OR, 1.96; P = .02). Girls whose mother or aunt had BC saw their BBD risk elevated with higher PHV (OR, 1.82 [inch/yr]; P = .05). Among girls with no family history, BBD risk appeared to be related to other factors: childhood BMI, adolescent waist circumference, and adult height.

CONCLUSIONS

Adolescents with family history may reduce their risk by avoiding alcohol. Separate risk factors were observed among girls with family history versus girls with no family history, possibly reflecting different causes of BC.

Prospective study of growth and development in older girls and risk of benign breast disease in young women

BACKGROUND

In adult women with retrospective data, childhood adiposity, pubertal growth and development were associated with benign breast disease (BBD) and/or breast cancer. The authors prospectively evaluated these childhood/adolescent characteristics and BBD risk.

METHODS

The Growing Up Today Study (GUTS) included females, aged 9-15 years in 1996, who completed annual questionnaires through 2001, then 2003, 2005, and 2007. Participants annually/biennially provided information on menarche, height, and weight, from which the authors derived body mass index (BMI in kg/m(2) ). Peak height growth velocity (PHV in cm/year) was estimated from longitudinal data. On 2005-2007 surveys, 6899 females (18-27 years of age) reported whether a healthcare provider ever diagnosed BBD (n = 147), and whether it was confirmed by biopsy (n = 67). Logistic models investigated risk factors adjusted for age, alcohol, pregnancy, and maternal history.

RESULTS

More childhood adiposity (odds ratio [OR], 0.91/[kg/m(2) ]; P = .04) and shorter adult height (OR, 0.93/inch shorter; P = .07) were associated with lower risk of biopsy-confirmed BBD. Girls with most rapid height growth were at increased risk (OR, 2.12; P = .09) relative to those with the slowest growth. Age at menarche was not associated (OR, 1.11/year; P = .32) nor was adult BMI (adjusted for childhood BMI: OR, 1.01/[kg/m(2) ]; P = .98); larger BMI increases (childhood to adulthood) were not protective (OR + 1.04/[kg/m(2) ]; P = .37). Among girls with maternal breast cancer, those with more rapid growth had higher risk (OR, 1.47/[cm/year]; P = .02). All estimates were age-adjusted.

CONCLUSIONS

Increased BBD risk (likely evolving to elevated breast cancer risk) was observed in thinner girls, girls with the most rapid growth, and taller women. Contrary to expectations, later menarche age was not protective against BBD, consistent with studies that found BBD patients are not protected against breast cancer by later menarche.