Body size, physical activity, and risk of triple-negative and estrogen receptor-positive breast cancer

Regular and low-dose aspirin, other non-steroidal anti-inflammatory medications and prospective risk of HER2-defined breast cancer: the California Teachers Study

BACKGROUND

Regular users of aspirin may have reduced risk of breast cancer. Few studies have addressed whether risk reduction pertains to specific breast cancer subtypes defined jointly by hormone receptor (estrogen and progesterone receptor) and human epidermal growth factor receptor 2 (HER2) expression. This study assessed the prospective risk of breast cancer (overall and by subtype) according to use of aspirin and other non-steroidal anti-inflammatory medications (NSAIDs) in a cohort of female public school professionals in California.

METHODS

In 1995 - 1996, participants in the California Teachers Study completed a baseline questionnaire on family history of cancer and other conditions, use of NSAIDs, menstrual and reproductive history, self-reported weight and height, living environment, diet, alcohol use, and physical activity. In 2005-2006, 57,164 participants provided some updated information, including use of NSAIDs and 1457 of these participants developed invasive breast cancer before January 2013. Multivariable Cox proportional hazards regression models provided hazard rate ratios (HRR) for the association between NSAID use and risk of invasive breast cancer as well as hormone receptor- and HER2-defined subtypes.

RESULTS

Developing breast cancer was associated inversely with taking three or more tablets of low-dose aspirin per week (23% of participants). Among women reporting this exposure, the HRR was 0.84 (95% confidence interval (CI) 0.72-0.98) compared to those not taking NSAIDs and this was particularly evident in women with the hormone receptor-positive/HER2-negative subtype (HRR = 0.80, 95% CI 0.66-0.96). Use of three or more tablets of "other" NSAIDs was marginally associated with lower risk of breast cancer (HRR = 0.79, 95% CI 0.62-1.00). Other associations with NSAIDs were generally null.

CONCLUSION

Our observation of reduced risk of breast cancer, among participants who took three or more tablets of low-dose aspirin weekly, is consistent with other reports looking at aspirin without differentiation by dose. This is the first report to suggest that the reduction in risk occurs for low-dose aspirin and not for regular-dose aspirin and only among women with the hormone receptor-positive/HER2-negative subtype. This preliminary study builds on previous knowledge and further supports the need for formal cancer chemoprevention studies of low-dose aspirin.

Treating triple negative breast cancer cells with erlotinib plus a select antioxidant overcomes drug resistance by targeting cancer cell heterogeneity

Among breast cancer patients, those diagnosed with the triple-negative breast cancer (TNBC) subtype have the worst prog-nosis. TNBC does not express estrogen receptor-alpha, progesterone receptor, or the HER2 oncogene; therefore, TNBC lacks targets for molecularly-guided therapies. The concept that EGFR oncogene inhibitor drugs could be used as targeted treatment against TNBC has been put forth based on estimates that 30-60% of TNBC express high levels of EGFR. However, results from clinical trials testing EGFR inhibitors, alone or in combination with cytotoxic chemotherapy, did not improve patient outcomes. Results herein offer an explanation as to why EGFR inhibitors failed TNBC patients and support how combining a select antioxidant and an EGFR-specific small molecule kinase inhibitor (SMKI) could be an effective, novel therapeutic strategy. Treatment with CAT-SKL-a re-engineered protein form of the antioxidant enzyme catalase-inhibited cancer stem-like cells (CSCs), and treatment with the EGFR-specific SMKI erlotinib inhibited non-CSCs. Thus, combining the antioxidant CAT-SKL with erlotinib targeted both CSCs and bulk cancer cells in cultures of EGFR-expressing TNBC-derived cells. We also report evidence that the mechanism for CAT-SKL inhibition of CSCs may depend on antioxidant-induced downregulation of a short alternative mRNA splicing variant of the methyl-CpG binding domain 2 gene, isoform MBD2c.

Disparities in Breastfeeding: Impact on Maternal and Child Health Outcomes and Costs

OBJECTIVE

To estimate the disease burden and associated costs attributable to suboptimal breastfeeding rates among non-Hispanic blacks (NHBs), Hispanics, and non-Hispanic whites (NHWs).

STUDY DESIGN

Using current literature on associations between breastfeeding and health outcomes for 8 pediatric and 5 maternal diseases, we used Monte Carlo simulations to evaluate 2 hypothetical cohorts of US women followed from age 15 to 70 years and their infants followed from birth to age 20 years. Accounting for differences in parity, maternal age, and birth weights by race/ethnicity, we examined disease outcomes and costs using 2012 breastfeeding rates by race/ethnicity and outcomes that would be expected if 90% of infants were breastfed according to recommendations for exclusive and continued breastfeeding duration.

RESULTS

Suboptimal breastfeeding is associated with a greater burden of disease among NHB and Hispanic populations. Compared with a NHW population, a NHB population had 1.7 times the number of excess cases of acute otitis media attributable to suboptimal breastfeeding (95% CI 1.7-1.7), 3.3 times the number of excess cases of necrotizing enterocolitis (95% CI 2.9-3.7), and 2.2 times the number of excess child deaths (95% CI 1.6-2.8). Compared with a NHW population, a Hispanic population had 1.4 times the number of excess cases of gastrointestinal infection (95% CI 1.4-1.4) and 1.5 times the number of excess child deaths (95% CI 1.2-1.9).

CONCLUSIONS

Racial/ethnic disparities in breastfeeding have important social, economic, and health implications, assuming a causal relationship between breastfeeding and health outcomes.

Correlates of Triple Negative Breast Cancer and Chemotherapy Patterns in Black and White Women With Breast Cancer

BACKGROUND

Triple negative breast cancer (TNBC) tumors are estrogen receptor-negative, progesterone receptor-negative, and human epidermal growth factor-negative. TNBC is responsive to chemotherapy, but chemotherapy might be underused in some patient subgroups. The goal of the present study was to characterize the patterns of chemotherapy use (uptake and completion) in TNBC patients.

PATIENTS AND METHODS

Women with primary invasive, nonmetastatic breast cancer were recruited in Washington, DC, and Detroit. Data were collected using a standardized telephone survey that captured sociocultural and health care process factors. Clinical data were abstracted from the medical records. We used χ² tests to access the association between the receipt of chemotherapy use (initiation and completion) and categorical variables, and t tests were used for continuous variables. Logistic regression models were used to evaluate the factors associated with chemotherapy uptake.

RESULTS

Women with TNBC (16% of sample) were more likely to be black than white (68% vs. 32%; P < .05). Among women with TNBC, 60% underwent chemotherapy. Chemotherapy uptake was greater for black than for white women (48.3% vs. 11.7%; P = .01) and in women without (vs. with) healthcare discrimination (35% vs. 25%; P = .04). In multivariable models, only race was associated with the receipt of chemotherapy. Black women were more likely to receive chemotherapy than were white women. The odds ratio of receiving chemotherapy by race was 4.1 (95% confidence interval, 1.3-13.1). Each 1-year increase in age was associated with a lower likelihood of chemotherapy completion (odds ratio, 0.9; 95% confidence interval, 0.826-0.981; P = .02). Women with at least some college were less likely to complete chemotherapy than were those with other education levels (P = .02).

CONCLUSION

A substantial number of TNBC patients failed to receive and/or complete chemotherapy. Differences in chemotherapy uptake by race and sociocultural factors diminished in multivariable models but age and stage remained significant. Suboptimal treatment among women with TNBC could contribute to adverse outcomes. Future investigations are necessary to assess whether the noninitiation and/or noncompletion of chemotherapy is clinically warranted.

Examining the relationship between sport and health among USA women: An analysis of the Behavioral Risk Factor Surveillance System

BACKGROUND

Research has been conducted linking sports participation and health in childhood and adolescence; however, little is known about the contribution of sport to women's health. The purpose of this study was to examine the relationship between sport and women's health in the USA by analyzing data from the Behavioral Risk Factor Surveillance System (BRFSS).

METHODS

This study was a secondary data analysis of the 2013 national BRFSS survey. Unlike the BRFSS core component from previous years, in 2013, participants were questioned extensively about their physical activity behaviors. Seventy-six different activities were identified by the participants. Two researchers categorized the 76 activities as sport, conditioning exercise, recreation, or household tasks based on previously identified categories. Logistic regression was utilized to calculate odds ratios and adjusted odds ratios for chronic diseases based on physical activity category.

RESULTS

Women who participated in sport had better health outcomes with significantly lower odds for all chronic diseases except asthma and better general health than women who participated in conditioning exercise, household tasks, or recreation, and many of the significant differences remained after controlling for demographic characteristics.

CONCLUSION

Sport participation was associated with more positive health outcomes among women in the USA compared with the other categories. As a means to improve health of women, the USA could focus on efforts to increase sport participation among women.

Central obesity and risks of pre- and postmenopausal breast cancer: a dose-response meta-analysis of prospective studies

Epidemiologic evidence has shown inconsistent findings regarding the relationships between abdominal fatness, as measured by waist circumferences (WC) or waist-to-hip ratio (WHR), and risks of pre- and postmenopausal breast cancer (BC). A dose-response meta-analysis of prospective studies was conducted to address these issues. Potentially eligible studies were identified by searching PubMed and EMBASE databases, and by carefully reviewing the bibliographies of retrieved publications and related reviews. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model. When the most fully adjusted RRs were combined, both WC (14 studies, RR _{per 10-cm increase}  = 1.06, 95% CI: 1.04-1.09, I²  = 29.9%) and WHR (15 studies, RR _{per 0.1-unit increase}  = 1.07, 95% CI: 1.01-1.14, I²  = 52.9%) were significantly positively associated with postmenopausal BC, but neither WC (eight studies, RR _{per 10-cm increase}  = 1.05, 95% CI: 0.99-1.10, I²  = 0%) nor WHR (11 studies, RR _{per 0.1-unit increase}  = 1.07, 95% CI: 0.95-1.21, I²  = 59.7%) were associated with premenopausal BC. The WHR-postmenopausal BC association lost statistical significance after correcting publication bias (RR _{per 0.1-unit increase}  = 1.06, 95% CI: 0.99-1.13). When considering BMI-adjusted RRs, WC was associated with both pre- (five studies, RR _{per 10-cm increase}  = 1.09, 95% CI: 1.02-1.16, I²  = 0%) and postmenopausal BC (seven studies, RR _{per 10-cm increase}  = 1.05, 95% CI: 1.02-1.08, I²  = 6.3%), whereas WHR was not associated with either pre- (seven studies, RR _{per 0.1-unit increase}  = 1.12, 95% CI: 0.94-1.34, I²  = 70.9%) or postmenopausal BC (eight studies, RR _{per 0.1-unit increase}  = 1.05, 95% CI: 0.98-1.13, I²  = 57.3%). Among non-current (former or never) users of hormone replacement therapy, the summary RR _{per 10-cm increase} of postmenopausal BC associated with WC was 1.08 (95% CI: 1.03-1.05, I²  = 69.2%, seven studies; BMI-adjusted RR = 1.05, 95% CI: 1.02-1.09, I²  = 22.8%, four studies). This meta-analysis indicates that central obesity measured by WC, but not by WHR, is associated with modestly increased risks of both pre- and postmenopausal BC independent of general obesity.

The association between body mass index and immunohistochemical subtypes in breast cancer

BACKGROUND

Body mass index (BMI) is defined as a poor prognostic factor in patients with breast cancer (BC). However, there are controversial results regarding the various effects of BMI on BC, hence the exact pathophysiology of the relation between obesity and BC is still under debate, and remains unclear. This paper aims to investigate the association between BMI at presentation and BC subtypes defined according to the immunohistochemical classification in both premenopausal and postmenopausal patients with BC.

PATIENTS AND METHODS

This study is a retrospective and explorative analysis of the 3767 female BC patients from a single center. All patients' BMI at the time of initial diagnosis and tumor demographics were recorded. BMI was stratified into 3 groups as normal-weighted (BMI <25 kg/m²), over-weighted (BMI = 25-29.9 kg/m²), and obese (BMI ≥30 kg/m²). Immunohistochemical classification of the tumors was categorized into 4 groups as follows; luminal-like, HER2/luminal-like, HER2-like, and triple-negative according to the ER/PR and HER2 status. Distribution of Immunohistochemical subtypes, tumor characteristics, and overall survival (OS) analysis were evaluated according to the BMI groups in both premenopausal and postmenopausal patients.

RESULTS

Median BMI of premenopausal and postmenopausal patients was 25.5 (kg/m²) and 28.8 (kg/m²), respectively (P < 0.001). In parallel with the increasing age, patients were more obese at diagnosis in both premenopausal (P < 0.001) and postmenopausal period (P < 0.001). Triple-negative subtype was significantly more frequent in premenopausal patients with BMI ≥30 kg/m² compared to BMI <30 kg/m² (P = 0.007). Additionally, premenopausal patients with BMI ≥30 kg/m² had less common luminal-like subtype (P = 0.033) and more frequently presented with higher tumor stage (P = 0.012) and tumor grade (P = 0.004) compared to patients with BMI <25 kg/m². On the other hand, premenopausal patients with BMI <25 kg/m² had significantly more ER-positive tumors (P < 0.001) and lower stages of disease (P = 0.01) compared to their counterparts with BMI ≥25 kg/m². Premenopausal obese patients with triple-negative (P = 0.001) and luminal-like subtype (P = 0.002) had significantly shorter OS duration compared to overweight counterparts. HER2/luminal-like subtype was found to be significantly greater in postmenopausal overweight patients (P = 0.005). However, BMI had no any other significant effect on survival and immunohistochemical subtypes in postmenopausal patients. Multivariate analysis revealed that triple-negative subtype, grade III tumor, BMI ≥30 kg/m², T3-4 (P < 0.001), nodal involvement, metastatic disease, and lymphovascular involvement were significantly associated with poorer OS.

CONCLUSION

Our data indicated that BMI was an independent factor in patients with BC, with an association indicating a decreased incidence for luminal-like subtype and increased incidence for triple-negative subtype among premenopausal patients. However, this significance was not found in postmenopausal patients. Accordingly, a plausible etiological heterogeneity in BC might play a role among immunohistochemical subtypes in every life stage of women.

Central obesity increases risk of breast cancer irrespective of menopausal and hormonal receptor status in women of South Asian Ethnicity

BACKGROUND

Current evidence suggests that the relationship between obesity and breast cancer (BC) risk may vary between ethnic groups.

METHODS

A total of 1633 BC cases and 1504 controls were enrolled in hospital-based case-control study in Mumbai, India, from 2009 to 2013. Along with detailed questionnaire, we collected anthropometric measurements on all participants. We used unconditional logistic regression models to estimate odds ratios (ORs) and 95% confidence interval (CI) for BC risk associated with anthropometry measurements, stratified on tumour subtype and menopausal status.

RESULTS

Waist-to-hip ratio (WHR) of ≥0.95 was strongly associated with risk of BC compared to WHR ≤0.84 in both premenopausal (OR = 4.3; 95% CI: 2.9-6.3) and postmenopausal women (OR = 3.4; 95% CI: 2.4-4.8) after adjustment for body mass index (BMI). Premenopausal women with a BMI ≥30 were at lower risk compared to women with normal BMI (OR = 0.5; 95% CI: 0.4-0.8). A similar protective effect was observed in women who were postmenopausal for <10 years (OR = 0.6; 95% CI: 0.4-0.9) but not in women who were postmenopausal for ≥10 years (OR = 1.8; 95% CI: 1.1-3.3). Overweight and obese women (BMI: 25-29.9 and ≥ 30 kg/m(2), respectively) were at increased BC risk irrespective of menopausal status if their WHR ≥0.95. Central obesity (measured in terms of WC and WHR) increased the risk of both premenopausal and postmenopausal BCs irrespective of hormone receptor (HR) status.

CONCLUSIONS

Central obesity appears to be a key risk factor for BC irrespective of menopausal or HR status in Indian women with no history of hormone replacement therapy.

Duration of Adulthood Overweight, Obesity, and Cancer Risk in the Women's Health Initiative: A Longitudinal Study from the United States

BACKGROUND

High body mass index (BMI) has become the leading risk factor of disease burden in high-income countries. While recent studies have suggested that the risk of cancer related to obesity is mediated by time, insights into the dose-response relationship and the cumulative impact of overweight and obesity during the life course on cancer risk remain scarce. To our knowledge, this study is the first to assess the impact of adulthood overweight and obesity duration on the risk of cancer in a large cohort of postmenopausal women.

METHODS AND FINDINGS

Participants from the observational study of the Women's Health Initiative (WHI) with BMI information from at least three occasions during follow-up, free of cancer at baseline, and with complete covariate information were included (n = 73,913). Trajectories of BMI across ages were estimated using a quadratic growth model; overweight duration (BMI ≥ 25 kg/m2), obesity duration (BMI ≥ 30 kg/m2), and weighted cumulative overweight and obese years, which take into account the degree of overweight and obesity over time (a measure similar to pack-years of cigarette smoking), were calculated using predicted BMIs. Cox proportional hazard models were applied to determine the cancer risk associated with overweight and obesity duration. In secondary analyses, the influence of important effect modifiers and confounders, such as smoking status, postmenopausal hormone use, and ethnicity, was assessed. A longer duration of overweight was significantly associated with the incidence of all obesity-related cancers (hazard ratio [HR] per 10-y increment: 1.07, 95% CI 1.06-1.09). For postmenopausal breast and endometrial cancer, every 10-y increase in adulthood overweight duration was associated with a 5% and 17% increase in risk, respectively. On adjusting for intensity of overweight, these figures rose to 8% and 37%, respectively. Risks of postmenopausal breast and endometrial cancer related to overweight duration were much more pronounced in women who never used postmenopausal hormones. This study has limitations because some of the anthropometric information was obtained from retrospective self-reports. Furthermore, data from longitudinal studies with long-term follow-up and repeated anthropometric measures are typically subject to missing data at various time points, which was also the case in this study. Yet, this limitation was partially overcome by using growth curve models, which enabled us to impute data at missing time points for each participant.

CONCLUSIONS

In summary, this study showed that a longer duration of overweight and obesity is associated with an increased risk of developing several forms of cancer. Furthermore, the degree of overweight experienced during adulthood seemed to play an important role in the risk of developing cancer, especially for endometrial cancer. Although the observational nature of our study precludes inferring causality or making clinical recommendations, our findings suggest that reducing overweight duration in adulthood could reduce cancer risk and that obesity prevention is important from early onset. If this is true, health care teams should recognize the potential of obesity management in cancer prevention and that excess body weight in women is important to manage regardless of the age of the patient.

The Obesity-Breast Cancer Conundrum: An Analysis of the Issues

Breast cancer develops over a timeframe of 2-3 decades prior to clinical detection. Given this prolonged latency, it is somewhat unexpected from a biological perspective that obesity has no effect or reduces the risk for breast cancer in premenopausal women yet increases the risk for breast cancer in postmenopausal women. This conundrum is particularly striking in light of the generally negative effects of obesity on breast cancer outcomes, including larger tumor size at diagnosis and poorer prognosis in both pre- and postmenopausal women. This review and analysis identifies factors that may contribute to this apparent conundrum, issues that merit further investigation, and characteristics of preclinical models for breast cancer and obesity that should be considered if animal models are used to deconstruct the conundrum.

Recreational physical activity and risk of triple negative breast cancer in the California Teachers Study

BACKGROUND

Evidence has accumulated showing that recreational physical activity reduces breast cancer risk. However, it is unclear whether risk reduction pertains to specific receptor-defined subtypes. Moreover, few studies have examined whether changes in the amount of recreational physical activity during adulthood influence breast cancer risk.

METHODS

A total of 108,907 women, ages 22 to 79 years with no history of breast cancer when joining the California Teachers Study in 1995-1996, completed a baseline questionnaire and were eligible for the study. Through 2012, 5882 women were diagnosed with invasive breast cancer. Breast cancer subtypes were defined by the expression status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Multivariable Cox proportional hazards models provided adjusted hazard ratios (HRs) and 95 % confidence intervals (CIs) for breast cancer overall and ER/PR/HER2-defined subtypes associated with long-term (from high school through age 54 or age at cohort entry, whichever was younger) and baseline (during 3 years prior to baseline) recreational physical activity. Among women who also completed a follow-up questionnaire at 10 years after baseline in 2005-2008 (54,686 women, 1406 with invasive breast cancer), risk associated with changes in the amount of recreational physical activity from baseline to the 10-year follow-up (during 3 years prior to the 10-year follow-up) was determined.

RESULTS

Both long-term and baseline strenuous recreational physical activity were inversely associated with risk of invasive breast cancer (P trend ≤0.03). The observed associations were mainly confined to women with triple negative breast cancer (TNBC, ER-/PR-/HER2-, P trend ≤0.02) or luminal A-like subtype (ER+ or PR+ plus HER2-) who were former users of menopausal hormone therapy at baseline (P trend = 0.02, P homogeneity of trends ≤0.03). Moreover, women who consistently engaged in the highest level (≥3.51 h/wk/y) of strenuous recreational physical activity between baseline and 10-year follow-up had the lowest risk of breast cancer (HR = 0.71, 95 % CI = 0.52-0.98) when compared to those who were consistently low (≤0.50 h/wk/y).

CONCLUSIONS

Strenuous recreational physical activity is associated with lower breast cancer risk, especially TNBC. The benefit may be maximized by consistently engaging in high-intensity recreational physical activity during adulthood.

Body mass index and risk of luminal, HER2-overexpressing, and triple negative breast cancer

Triple negative (TN, tumors that do not express estrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor 2 (HER2)) and HER2-overexpressing (H2E, ER-/HER2+) tumors are two particularly aggressive subtypes of breast cancer. There is a lack of knowledge regarding the etiologies of these cancers and in particular how anthropometric factors are related to risk. We conducted a population-based case-case study consisting of 2659 women aged 20-69 years diagnosed with invasive breast cancer from 2004 to 2012. Four case groups defined based on joint ER/PR/HER2 status were included: TN, H2E, luminal A (ER+/HER2-), and luminal B (ER+/HER2+). Polytomous logistic regression was used to estimate odds ratios (ORs) and associated 95 % confidence intervals (CIs) where luminal A patients served as the reference group. Obese premenopausal women [body mass index (BMI) ≥30 kg/m(2)] had an 82 % (95 % CI 1.32-2.51) increased risk of TN breast cancer compared to women whose BMI <25 kg/m(2), and those in the highest weight quartile (quartiles were categorized based on the distribution among luminal A patients) had a 79 % (95 % CI 1.23-2.64) increased risk of TN disease compared to those in the lowest quartile. Among postmenopausal women obesity was associated with reduced risks of both TN (OR = 0.74, 95 % CI 0.54-1.00) and H2E (OR = 0.47, 95 % CI 0.32-0.69) cancers. Our results suggest obesity has divergent impacts on risk of aggressive subtypes of breast cancer in premenopausal versus postmenopausal women, which may contribute to the higher incidence rates of TN cancers observed among younger African American and Hispanic women.

Impact of central obesity on prognostic outcome of triple negative breast cancer in Chinese women

Purpose

To evaluate the prognostic effect of central obesity on triple negative breast cancer (TNBC).

Methods

206 TNBC patients treated from June 2006 to June 2015 were enrolled retrospectively. Body mass index (BMI) ≥25 kg/m² was the standard of obesity and waist circumference ≥80 cm was the standard of central obesity. Patient and tumor characteristics were compared between obesity categories. Survival differences between obesity categories were assessed with log-rank test in the univariate analysis and prognostic factors were then investigated by Cox regression analysis.

Results

81 cases were with obesity (39.3 %). 71 cases were with central obesity (34.5 %). Patients with obesity or central obesity tended to be older (P = 0.022 for obesity; P = 0.013 for central obesity) and to have larger tumor size (P = 0.027 for obesity; P = 0.027 for central obesity). By Cox regression analysis, central obesity (DFS: HR 1.759; 95 % CI 1.009–3.065; P = 0.046. OS: HR 2.297; 95 % CI 1.184–4.456; P = 0.014) was identified as an independent prognostic factor. For central obesity with BMI ≥ 25 kg/m², the prognostic effect was more apparent (DFS: HR 1.845; 95 % CI 1.059–3.212; P = 0.031. OS: HR 2.377; 95 % CI 1.230–4.593; P = 0.010).

Conclusion

Central obesity, especially with high BMI, was an independent prognostic factor for TNBC.

Obesity and Breast Cancer

The relationship between adiposity and breast cancer risk and prognosis is complex, with associations that differ depending on when body size is assessed (e.g., pre- vs. postmenopausal obesity) and when breast cancer is diagnosed (i.e., pre- vs. postmenopausal disease). Further, the impact of obesity on risk differs by tumor hormone receptor status (e.g., estrogen (ER) and progesterone (PR) receptor) and, among postmenopausal women, use of exogenous hormones (i.e., hormone replacement therapy (HRT)). In the context of these complexities, this review focuses on associations between childhood and adolescent adiposity, general adiposity, weight changes (i.e., loss and gain), abdominal adiposity, and breast cancer risk and survival. Finally, we discuss potential mechanisms linking adiposity to breast cancer.

Beyond Axillary Lymph Node Metastasis, BMI and Menopausal Status Are Prognostic Determinants for Triple-Negative Breast Cancer Treated by Neoadjuvant Chemotherapy

Background

Triple-negative breast cancers (TNBC) are a specific subtype of breast cancers with a particularly poor prognosis. However, it is a very heterogeneous subgroup in terms of clinical behavior and sensitivity to systemic treatments. Thus, the identification of risk factors specifically associated with those tumors still represents a major challenge. A therapeutic strategy increasingly used for TNBC patients is neoadjuvant chemotherapy (NAC). Only a subset of patients achieves a pathologic complete response (pCR) after NAC and have a better outcome than patients with residual disease.

Purpose

The aim of this study is to identify clinical factors associated with the metastatic-free survival in TNBC patients who received NAC.

Methods

We analyzed 326 cT1-3N1-3M0 patients with ductal infiltrating TNBC treated by NAC. The survival analysis was performed using a Cox proportional hazard model to determine clinical features associated with prognosis on the whole TNBC dataset. In addition, we built a recursive partitioning tree in order to identify additional clinical features associated with prognosis in specific subgroups of TNBC patients.

Results

We identified the lymph node involvement after NAC as the only clinical feature significantly associated with a poor prognosis using a Cox multivariate model (HR = 3.89 [2.42–6.25], p<0.0001). Using our recursive partitioning tree, we were able to distinguish 5 subgroups of TNBC patients with different prognosis. For patients without lymph node involvement after NAC, obesity was significantly associated with a poor prognosis (HR = 2.64 [1.28–5.55]). As for patients with lymph node involvement after NAC, the pre-menopausal status in grade III tumors was associated with poor prognosis (HR = 9.68 [5.71–18.31]).

Conclusion

This study demonstrates that axillary lymph node status after NAC is the major prognostic factor for triple-negative breast cancers. Moreover, we identified body mass index and menopausal status as two other promising prognostic factors in this breast cancer subgroup. Using these clinical factors, we were able to classify TNBC patients in 5 subgroups, for which pre-menopausal patients with grade III tumors and lymph node involvement after NAC have the worse prognosis.

Physical activity, hormone replacement therapy and breast cancer risk: A meta-analysis of prospective studies

BACKGROUND

Lower risk of breast cancer has been reported among physically active women, but the risk in women using hormone replacement therapy (HRT) appears to be higher. We quantified the association between physical activity and breast cancer, and we examined the influence that HRT use and other risk factors had on this association.

METHODS

After a systematic literature search, prospective studies were meta-analysed using random-effect models applied on highest versus lowest level of physical activity. Dose-response analyses were conducted with studies reporting physical activity either in hours per week or in hours of metabolic equivalent per week (MET-h/week).

RESULTS

The literature search identified 38 independent prospective studies published between 1987 and 2014 that included 116,304 breast cancer cases. Compared to the lowest level of physical activity, the highest level was associated with a summary relative risk (SRR) of 0.88 (95% confidence interval [CI] 0.85, 0.90) for all breast cancer, 0.89 (95% CI 0.83, 0.95) for ER+/PR+ breast cancer and 0.80 (95% CI 0.69, 0.92) for ER-/PR- breast cancer. Risk reductions were not influenced by the type of physical activity (occupational or non-occupational), adiposity, and menopausal status. Risk reductions increased with increasing amounts of physical activity without threshold effect. In six studies, the SRR was 0.78 (95% CI 0.70, 0.87) in women who never used HRT and 0.97 (95% CI 0.88, 1.07) in women who ever used HRT, without heterogeneity in results. Findings indicate that a physically inactive women engaging in at least 150 min per week of vigorous physical activity would reduce their lifetime risk of breast cancer by 9%, a reduction that might be two times greater in women who never used HRT.

CONCLUSION

Increasing physical activity is associated with meaningful reductions in the risk of breast cancer, but in women who ever used HRT, the preventative effect of physical activity seems to be cancelled out.

Risk factors and biomarkers of life-threatening cancers

There is growing evidence that risk factors for cancer occurrence and for cancer death are not necessarily the same. Knowledge of cancer aggressiveness risk factors (CARF) may help in identifying subjects at high risk of developing a potentially deadly cancer (and not just any cancer). The availability of CARFs may have positive consequences for health policies, medical practice, and the search for biomarkers. For instance, cancer chemoprevention and cancer screening of subjects with CARFs would probably be more ethical and cost-effective than recommending chemoprevention and screening to entire segments of the population. Also, the harmful consequences of chemoprevention and of screening would be reduced while effectiveness would be optimised. We present examples of CARF already in use (e.g. mutations of the breast cancer (BRCA) gene), of promising avenues for the discovery of biomarkers thanks to the investigation of CARFs (e.g. breast radiological density and systemic inflammation), and of biomarkers commonly used that are not real CARFs (e.g. certain mammography images, prostate-specific antigen (PSA) concentration, nevus number).

Breast cancer risk factor associations differ for pure versus invasive carcinoma with an in situ component in case-control and case-case analyses

PURPOSE

Invasive ductal carcinoma (IDC) is diagnosed with or without a ductal carcinoma in situ (DCIS) component. Previous analyses have found significant differences in tumor characteristics between pure IDC lacking DCIS and mixed IDC with DCIS. We will test our hypothesis that pure IDC represents a form of breast cancer with etiology and risk factors distinct from mixed IDC/DCIS.

METHODS

We compared reproductive risk factors for breast cancer risk, as well as family and smoking history between 831 women with mixed IDC/DCIS (n = 650) or pure IDC (n = 181), and 1,620 controls, in the context of the Women's Circle of Health Study (WCHS), a case-control study of breast cancer in African-American and European-American women. Data on reproductive and lifestyle factors were collected during interviews, and tumor characteristics were abstracted from pathology reports. Case-control and case-case analyses were conducted using unconditional logistic regression.

RESULTS

Most risk factors were similarly associated with pure IDC and mixed IDC/DCIS. However, among postmenopausal women, risk of pure IDC was lower in women with body mass index (BMI) 25 to <30 [odds ratio (OR) 0.66; 95 % confidence interval (CI) 0.35-1.23] and BMI ≥ 30 (OR 0.33; 95 % CI 0.18-0.67) compared to women with BMI < 25, with no associations with mixed IDC/DCIS. In case-case analyses, women who breastfed up to 12 months (OR 0.55; 95 % CI 0.32-0.94) or longer (OR 0.47; 95 % CI 0.26-0.87) showed decreased odds of pure IDC than mixed IDC/DCIS compared to those who did not breastfeed.

CONCLUSIONS

Associations with some breast cancer risk factors differed between mixed IDC/DCIS and pure IDC, potentially suggesting differential developmental pathways. These findings, if confirmed in a larger study, will provide a better understanding of the developmental patterns of breast cancer and the influence of modifiable risk factors, which in turn could lead to better preventive measures for pure IDC, which have worse disease prognosis compared to mixed IDC/DCIS.

Correlation of Physical Activities and Breast Cancer Characteristics: A Prospective Analysis with Special Focus on Triple Negative Breast Cancer

OBJECTIVE

Several studies have demonstrated that daily physical activity (PA) prevents the development of breast cancer. Our objective was to examine the relationship between PA and clinical and biological tumor characteristics in breast cancer patients in order to determine the impact of energy expenditure (EE) on tumor prognosis.

METHODS

We pooled data from two prospective studies, including a total of 121 breast cancer patients. The measure of PA was done using the self-completion Population Physical Activity Questionnaire, which was answered by each patient.

RESULTS

Ten patients harbored triple negative (TN) tumors. The mean body mass index (BMI) in the general population and in patients with TN tumors was 24.3 and 25.6, respectively. The mean daily EE (DEE) was 10,266 kJ×24 h(-1) in the general population and 11,212 kJ×24 h(-1) in patients with TN tumors. In the whole population, there was an inverse statistical correlation between BMI and DEE, rest, low PA, and high PA (p=0.0002, p=0.003, p<0001, and p=0.03, respectively). There was a positive correlation between negative estrogen receptor status and intensive PA (p=0.041) and DEE (p=0.007). For TN tumors, there was no significant correlation between BMI and categories of EE.

CONCLUSIONS

Lifestyle (weight regulation, PA) should be adapted and personalized according to biological, clinical, and epidemiological characteristics of the tumors.

Adiposity and cancer risk: new mechanistic insights from epidemiology

Excess body adiposity, commonly expressed as body mass index (BMI), is a risk factor for many common adult cancers. Over the past decade, epidemiological data have shown that adiposity-cancer risk associations are specific for gender, site, geographical population, histological subtype and molecular phenotype. The biological mechanisms underpinning these associations are incompletely understood but need to take account of the specificities observed in epidemiology to better inform future prevention strategies.

New approaches for improving outcomes in breast cancer in Europe

Considerable progress has been made in breast cancer treatment in Europe over the past three decades, yet survival rates for metastatic disease remain poor, underlining the need for further advances. While the use of predictive biomarkers for response to systemic therapy could improve drug development efficiency, progress in identifying such markers has been slow. The currently inadequate classification of breast cancer subtypes is a further challenge. Improved understanding of the molecular pathology of the disease has led to the identification of new targets for drug treatment, and evolving classifications should reflect these developments. Further ongoing challenges include difficulties in finding optimal combinations and sequences of systemic therapies, circumventing multidrug resistance and intra-tumor heterogeneity, problems associated with fragmentation in clinical trials and translational research efforts. Adoption of some of the strategies identified in this article may lead to further improvements in outcomes for patients with the disease.

The phosphorylated prodrug FTY720 is a histone deacetylase inhibitor that reactivates ERα expression and enhances hormonal therapy for breast cancer

Estrogen receptor-α (ERα)-negative breast cancer is clinically aggressive and does not respond to conventional hormonal therapies. Strategies that lead to re-expression of ERα could sensitize ERα-negative breast cancers to selective ER modulators. FTY720 (fingolimod, Gilenya), a sphingosine analog, is the Food and Drug Administration (FDA)-approved prodrug for treatment of multiple sclerosis that also has anticancer actions that are not yet well understood. We found that FTY720 is phosphorylated in breast cancer cells by nuclear sphingosine kinase 2 and accumulates there. Nuclear FTY720-P is a potent inhibitor of class I histone deacetylases (HDACs) that enhances histone acetylations and regulates expression of a restricted set of genes independently of its known effects on canonical signaling through sphingosine-1-phosphate receptors. High-fat diet (HFD) and obesity, which is now endemic, increase breast cancer risk and have been associated with worse prognosis. HFD accelerated the onset of tumors with more advanced lesions and increased triple-negative spontaneous breast tumors and HDAC activity in MMTV-PyMT transgenic mice. Oral administration of clinically relevant doses of FTY720 suppressed development, progression and aggressiveness of spontaneous breast tumors in these mice, reduced HDAC activity and strikingly reversed HFD-induced loss of estrogen and progesterone receptors in advanced carcinoma. In ERα-negative human and murine breast cancer cells, FTY720 reactivated expression of silenced ERα and sensitized them to tamoxifen. Moreover, treatment with FTY720 also re-expressed ERα and increased therapeutic sensitivity of ERα-negative syngeneic breast tumors to tamoxifen in vivo more potently than a known HDAC inhibitor. Our work suggests that a multipronged attack with FTY720 is a novel combination approach for effective treatment of both conventional hormonal therapy-resistant breast cancer and triple-negative breast cancer.

Obesity and male breast cancer: provocative parallels?

While rare compared to female breast cancer the incidence of male breast cancer (MBC) has increased in the last few decades. Without comprehensive epidemiological studies, the explanation for the increased incidence of MBC can only be speculated. Nevertheless, one of the most worrying global public health issues is the exponential rise in the number of overweight and obese people, especially in the developed world. Although obesity is not considered an established risk factor for MBC, studies have shown increased incidence among obese individuals. With this observation in mind, this article highlights the correlation between the increased incidence of MBC and the current trends in obesity as a growing problem in the 21(st) century, including how this may impact treatment. With MBC becoming more prominent we put forward the notion that, not only is obesity a risk factor for MBC, but that increasing obesity trends are a contributing factor to its increased incidence.

Lifestyle and Breast Cancer Incidence and Survival

Recently reported SEER data revealing an increase in the number of younger women who present with advanced breast cancer at diagnosis has led to much speculation regarding epidemiological factors that play a role in breast cancer risk and that may be modifiable by lifestyle. Molecular genomics has identified biological pathways that affect breast cancer prognosis and inform treatment decisions. Depending on menopausal status and breast cancer subtype, evidence is emerging that lifestyle could be implicated not only in the risk for breast cancer but also outcomes following breast cancer diagnosis. Several biologic mechanisms have been explored explaining the physiologic role of lifestyle and cancer risk and survival. In this report, we explore the interaction between lifestyle, breast cancer phenotype, and outcomes and review potential molecular mechanisms linking lifestyle to risk and prognosis in order to establish a platform for future exploration. The cost of breast cancer treatment and breast cancer morbidity and mortality during a woman’s productive years impose a psychosocial and socioeconomic burden on our nation. Efforts to ease that burden through lifestyle modification should be embraced and supported as we reevaluate and scrutinize the allocation of health care resources in our nation.

Reduced risk of breast cancer associated with recreational physical activity varies by HER2 status

Convincing epidemiologic evidence indicates that physical activity is inversely associated with breast cancer risk. Whether this association varies by the tumor protein expression status of the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), or p53 is unclear. We evaluated the effects of recreational physical activity on risk of invasive breast cancer classified by the four biomarkers, fitting multivariable unconditional logistic regression models to data from 1195 case and 2012 control participants in the population-based Women’s Contraceptive and Reproductive Experiences Study. Self-reported recreational physical activity at different life periods was measured as average annual metabolic equivalents of energy expenditure [MET]-hours per week. Our biomarker-specific analyses showed that lifetime recreational physical activity was negatively associated with the risks of ER-positive (ER+) and of HER2-negative (HER2−) subtypes (both P_trend ≤ 0.04), but not with other subtypes (all P_trend > 0.10). Analyses using combinations of biomarkers indicated that risk of invasive breast cancer varied only by HER2 status. Risk of HER2–breast cancer decreased with increasing number of MET-hours of recreational physical activity in each specific life period examined, although some trend tests were only marginally statistically significant (all P_trend ≤ 0.06). The test for homogeneity of trends (HER2– vs. HER2+ ) reached statistical significance only when evaluating physical activity during the first 10 years after menarche (P_homogeneity = 0.03). Our data suggest that physical activity reduces risk of invasive breast cancers that lack HER2 overexpression, increasing our understanding of the biological mechanisms by which physical activity acts.

Targeting the COX-2 Pathway to Improve Therapeutic Response in the Obese Breast Cancer Patient Population

Multiple studies have demonstrated that obesity is associated with a worse outcome for all breast cancer subtypes and that obese breast cancer patients do not respond as well as normal weight patients to aromatase inhibitor treatment and chemotherapy. While a number of mechanisms have been proposed to explain this link, recent studies have provided evidence that elevated local cyclooxygenase-2 (COX-2) expression and the resulting increase in prostaglandin E2 (PGE2) production may play an important role. COX-2 upregulation in breast tumors is associated with a poor prognosis, a connection generally attributed to PGE2's direct effects on apoptosis and invasion as well as its stimulation of pre-adipocyte aromatase expression and subsequent estrogen production. Research in this area has provided a strong foundation for the hypothesis that COX-2 signaling is involved in the obesity-breast cancer link, and further study regarding the role of COX-2 in this link is warranted.

Obesity, body fat distribution, and risk of breast cancer subtypes in African American women participating in the AMBER Consortium

African American (AA) women are more likely than white women to be obese and to be diagnosed with ER- and triple-negative (TN) breast cancer, but few studies have evaluated the impact of obesity and body fat distribution on breast cancer subtypes in AA women. We evaluated these associations in the AMBER Consortium by pooling data from four large studies. Cases were categorized according to hormone receptor status as ER+, ER-, and TN (ER-, PR-, and HER2-) based on pathology data. A total of 2104 ER+ cases, 1070 ER- cases (including 491 TN cases), and 12,060 controls were included. Odds ratios (OR) and 95 % confidence intervals (CI) were computed using logistic regression, taking into account breast cancer risk factors. In postmenopausal women, higher recent (most proximal value to diagnosis/index date) BMI was associated with increased risk of ER+ cancer (OR 1.31; 95 % CI 1.02-1.67 for BMI ≥ 35 vs. <25 kg/m(2)) and with decreased risk of TN tumors (OR 0.60; 95 % CI 0.39-0.93 for BMI ≥ 35 vs. <25). High young adult BMI was associated with decreased premenopausal ER+ cancer and all subtypes of postmenopausal cancer, and high recent waist-to-hip ratio with increased risk of premenopausal ER+ tumors (OR 1.35; 95 % CI 1.01-1.80) and all tumor subtypes combined in postmenopausal women (OR 1.26; 95 % CI 1.02-1.56). The impact of general and central obesity varies by menopausal status and hormone receptor subtype in AA women. Our findings imply different mechanisms for associations of adiposity with TN and ER+ breast cancers.

Tumor mechanics and metabolic dysfunction

Desmosplasia is a characteristic of most solid tumors and leads to fibrosis through abnormal extracellular matrix (ECM) deposition, remodeling, and posttranslational modifications. The resulting stiff tumor stroma not only compromises vascular integrity to induce hypoxia and impede drug delivery, but also promotes aggressiveness by potentiating the activity of key growth, invasion, and survival pathways. Intriguingly, many of the protumorigenic signaling pathways that are mechanically activated by ECM stiffness also promote glucose uptake and aerobic glycolysis, and an altered metabolism is a recognized hallmark of cancer. Indeed, emerging evidence suggests that metabolic alterations and an abnormal ECM may cooperatively drive cancer cell aggression and treatment resistance. Accordingly, improved methods to monitor tissue mechanics and metabolism promise to improve diagnostics and treatments to ameliorate ECM stiffening and elevated mechanosignaling may improve patient outcome. Here we discuss the interplay between ECM mechanics and metabolism in tumor biology and suggest that monitoring these processes and targeting their regulatory pathways may improve diagnostics, therapy, and the prevention of malignant transformation.

The role of body size and physical activity on the risk of breast cancer in BRCA mutation carriers

Women who inherit a BRCA mutation face a high lifetime risk of developing breast cancer. Given the high penetrance of these mutations, prevention is of extreme importance. Here, we review the literature regarding the role of body size and of physical activity in the context of BRCA-associated breast cancer. There is some evidence to support a protective role of a healthy body size and of regular physical activity among mutation carriers, particularly during adolescence or early adulthood. Factors which increase the physiologic expression of the normal copy of the BRCA1 or BRCA2 gene and thereby normalize protein levels, contribute to stem cell homeostasis, and/or affect hormone levels, might mitigate the effects of an inherited BRCA mutation. Preliminary evidence from one in vivo study and from one epidemiologic report suggests that an increase in BRCA1 mRNA expression occurs with increasing levels of physical activity. The prospect of changing lifestyle for the purpose of preventing breast cancer in high-risk women, complemented by mechanistic evidence, warrants evaluation in large-scale prospective studies.

The 2014 Society of Surgical Oncology Susan G. Komen for the Cure Symposium: triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an operational term that refers to a heterogeneous collection of breast cancers lacking expression of estrogen receptor (ER), progesterone receptor, and HER2. These tumors account for 12-17 % of all breast cancers, preferentially affect young women, are more frequent in women of African and Hispanic descent, and are enriched in the population of patients diagnosed with "interval cancers." TNBCs account for the majority of breast cancers arising in BRCA1 germline mutation carriers (approximately 80%), and approximately 11-16% of all TNBCs harbor BRCA1 or BRCA2 germline mutations. Well-known risk factors for ER-positive cancers, such as reproductive history and hormonal factors, do not appear to have the same correlations for TNBC, and histologic risk factors for TNBC have not been identified. Patients with TNBC have a higher risk of both local and distant recurrence, but this is not mitigated by bigger surgery, and standard criteria should be used to select the approach to local therapy in these patients. Although platinum drugs have shown promise in the treatment of TNBC, standard chemotherapy remains the standard of care outside of a clinical trial.

Body mass index and risk of breast cancer: a nonlinear dose-response meta-analysis of prospective studies

The role of Body Mass Index (BMI) for Breast Cancer (BC) remains to be great interest for a long time. However, the precise effect of nonlinear dose-response for BMI and BC risk is still unclear. We conducted a dose-response meta-analysis to quantitatively assess the effect of BMI on BC risk. Twelve prospective studies with 4,699 cases identified among 426,199 participants and 25 studies of 22,809 cases identified among 1,155,110 participants in premenopausal and postmenopausal groups, respectively, were included in this meta-analysis. Significant non-linear dose-response (P < 0.001) association was identified between BMI and BC risk in postmenopausal women. Individuals with BMI of 25, 30, and 35 kg/m² yielded relative risks (RRs) of 1.02 [95% confidence interval (CI): 0.98–1.06], 1.12 (95% CI: 1.01–1.24), and 1.26 (95% CI: 1.07–1.50), respectively, when compared to the mean level of the normal BMI range. However, inverse result though not significant was observed in premenopausal women. In conclusion, the results of this meta-analysis highlighted that obesity contributed to increased BC risk in a nonlinear dose-response manner in postmenopausal women, and it is important to realize that body weight control may be a crucial process to reduce BC susceptibility.

Obesity enhances nongenomic estrogen receptor crosstalk with the PI3K/Akt and MAPK pathways to promote in vitro measures of breast cancer progression

Introduction

Epidemiological and clinical studies indicate that obesity is associated with a worse postmenopausal breast cancer prognosis and an increased risk of endocrine therapy resistance. However, the mechanisms mediating these effects remain poorly understood. Here we investigate the molecular pathways by which obesity-associated circulating factors in the blood enhance estrogen receptor alpha (ERα) positive breast cancer cell viability and growth.

Methods

Blood serum was collected from postmenopausal breast cancer patients and pooled by body mass index (BMI) category (Control: 18.5 to 24.9 kg/m²; Obese: ≥30.0 kg/m²). The effects of patient sera on MCF-7 and T47D breast cancer cell viability and growth were examined by MTT and colony formation assays, respectively. Insulin-like growth factor receptor 1(IGF-1R), Akt, and ERK1/2 activation and genomic ERα activity were assessed to determine their possible contribution to obese patient sera-induced cell viability and growth. To further define the relative contribution of these signaling pathways, cells grown in patient sera were treated with various combinations of ERα, PI3K/Akt and MAPK targeted therapies. Comparisons between cells exposed to different experimental conditions were made using one-way analysis of variance (ANOVA) and Student's t test.

Results

Cells grown in media supplemented with obese patient sera displayed greater cell viability and growth as well as IGF-1R, Akt and ERK1/2 activation relative to control sera. Despite the lack of a significant difference in genomic ERα activity following growth in obese versus control patient sera, we observed a dramatic reduction in cell viability and growth after concurrent inhibition of the ERα and PI3K/Akt signaling pathways. Further, we demonstrated that ERα inhibition was sufficient to attenuate obese serum-induced Akt and ERK1/2 activation. Together, these data suggest that obesity promotes greater ERα positive breast cancer cell viability and growth through enhanced crosstalk between nongenomic ERα signaling and the PI3K/Akt and MAPK pathways.

Conclusions

Circulating factors in the serum of obese postmenopausal women stimulate ERα positive breast cancer cell viability and growth by facilitating non-genomic ERα crosstalk with the PI3K/Akt and MAPK signaling pathways. These findings provide valuable insight into one mechanism by which obesity may promote ERα positive postmenopausal breast cancer progression and endocrine therapy resistance.

Modern reproductive patterns associated with estrogen receptor positive but not negative breast cancer susceptibility

It has long been accepted that modern reproductive patterns are likely contributors to breast cancer susceptibility because of their influence on hormones such as estrogen and the importance of these hormones in breast cancer. We conducted a meta-analysis to assess whether this ‘evolutionary mismatch hypothesis’ can explain susceptibility to both estrogen receptor positive (ER-positive) and estrogen receptor negative (ER-negative) cancer. Our meta-analysis includes a total of 33 studies and examines parity, age of first birth and age of menarche broken down by estrogen receptor status. We found that modern reproductive patterns are more closely linked to ER-positive than ER-negative breast cancer. Thus, the evolutionary mismatch hypothesis for breast cancer can account for ER-positive breast cancer susceptibility but not ER-negative breast cancer.

Self-recalled Youth Physical Activity and Postmenopausal Cardiovascular Disease

OBJECTIVES

To evaluate the association between childhood physical activity and incident cardiovascular disease (CVD) during postmenopausal years.

METHODS

Proportional hazards and logistic regression were used describe the association between self-reported childhood physical activity and CVD incidence and mortality in 36,741 postmenopausal women.

RESULTS

Older women, African-Americans, or nondrinkers or past drinkers self-reported the highest levels of youth physical activity and women with a history of diabetes, hypertension, overweight or obesity, or current smoking reported the highest youth physical activity dose. Youth physical activity was not associated with CVD incidence (HR=1.11; 0.93, 1.34) or mortality (HR=1.2; 0.9, 1.73).

CONCLUSIONS

Self-reported youth activity was not associated with postmenopausal CVD incidence or mortality.

A prospective study of physical activity and breast cancer incidence in African-American women

BACKGROUND

Physical activity has been associated with reduced risk of breast cancer. Evidence on the association in African Americans is limited.

METHODS

With prospective data from the Black Women's Health Study, we assessed vigorous exercise and walking in relation to incidence of invasive breast cancer overall (n = 1,364), estrogen receptor-positive (ER(+), n = 688) cancer, and estrogen receptor-negative (ER(-), n = 405) cancer, based on 307,672 person-years of follow-up of 44,708 African-American women ages 30 years or older at enrollment. Cox proportional hazards models estimated incidence rate ratios (IRR) and 95% confidence intervals (CI).

RESULTS

Vigorous exercise at baseline was inversely associated with overall breast cancer incidence (Ptrend = 0.05): the IRR for ≥7 h/wk relative to <1 h/wk was 0.74 (95% CI, 0.57-0.96). The association did not differ by ER status. Brisk walking for ≥7 h/wk was associated with a reduction similar to that for vigorous exercise. Vigorous exercise at the age of 30 years, 21 years, or in high school was not associated with breast cancer incidence. Sitting for long periods at work or watching TV was not significantly associated with breast cancer incidence.

CONCLUSION

High levels of vigorous exercise or brisk walking may be associated with a reduction in incidence of breast cancer in African-American women.

IMPACT

These results provide informative data on a potential modifiable risk factor, exercise, for breast cancer in African-American women.

Inflammatory cytokine levels and breast cancer risk factors: racial differences of healthy Caucasian and African American women

PURPOSE/OBJECTIVES

To examine racial differences in inflammatory cytokine levels (interleukin [IL]-6 and interferon-gamma [IFN-γ]) and breast cancer (BC) risk factors between healthy Caucasian and African American women; to examine differences in relationships of inflammatory cytokine levels with BC risk factors between these groups of women; and to determine the independent contribution of race to IL-6 and IFN-γ after controlling for relevant covariates.

DESIGN

Cross-sectional and correlational descriptive design.

SETTING

Community surrounding a state university health system in the southeastern United States.

SAMPLE

113 healthy women (65 Caucasians and 48 African Americans) aged 20 years or older and not pregnant.

METHODS

Secondary analysis of data collected from self-report questionnaires and blood samples.

MAIN RESEARCH VARIABLES

Inflammatory cytokine levels, BC risk factors (age, age at menarche, age at first live birth, family history of BC, breast biopsy, breastfeeding history and duration, body mass index, and physical activity), and race.

FINDINGS

Significant racial differences were noted in IL-6 and IFN-γ levels, reproductive or hormonal and lifestyle BC risk factors, and relationships between African American and Caucasian women. Controlling for all other effects, race appeared to be a significant predictor for IL-6 and IFN-γ.

CONCLUSIONS

Racial differences in inflammatory cytokines and BC risk factors may provide partial evidence for existing racial disparities in BC for African American and Caucasian women. Additional studies are needed to confirm that potential.

IMPLICATIONS FOR NURSING

Additional biobehavioral research in racial disparities in BC may help to inform nurses to target race-specific modifications of lifestyle and behavioral factors to reduce BC health disparity between African American and Caucasian women.

KNOWLEDGE TRANSLATION

Being an African American woman predicted a higher level of inflammatory cytokine production after controlling for selected BC risk factors. Great potential exists for inflammatory responses as one of the underlying biologic mechanisms for existing BC disparity and for culturally tailored lifestyle or behavioral modification interventions for reducing BC risk and racial disparity.

Differential patterns of recurrence and specific survival between luminal A and luminal B breast cancer according to recent changes in the 2013 St Gallen immunohistochemical classification

INTRODUCTION

In 2011, the St Gallen panel introduced several changes in breast cancer classification, thereby creating the luminal B Her2- subtype. In 2013, the panel also included Ki67 overexpression and PR <20 % as risk factors, while excluding GH3 in the absence of increased Ki67. We compared the classification of 2011 modified with the new 2013 St Gallen classification.

PATIENTS AND METHOD

Consecutive breast cancer patients referred to the Breast Unit of the University Hospital Mútua Terrassa and Hospital of Terrassa for surgical treatment of either primary or recurrent tumors were prospectively included between 1997 and 2014. Eventually, 1,874 cases were included for the four-subtype analysis. The median follow-up was of 66 months.

RESULTS

Using the 2013 St Gallen classification no significant differences were found in specific mortality rates between luminal A and B subtypes. There were significant differences at 5, 10, and, 15 years if we excluded luminal A GH3 patients in the absence of increased Ki67 (p = 0.004, 0.005, and 0.007). Luminal A sub-type patients showed significantly less distant metastases than the rest, including luminal B Her2- patients (p < 0.001). Also, luminal B patients showed significantly less distant metastases than pure Her2 (0.05) and triple negative (TN) (p < 0.001). There were no differences between pure Her2 and TN patients (0.055), neither among the different luminal B sub-types.

CONCLUSION

GH3, PR, and Ki67 may all be discriminatory factors for metastasis and specific mortality. Therefore, we suggest including GH3 in the luminal B subtype in the absence of Ki67.

Association between mammographic density and basal-like and luminal A breast cancer subtypes

Introduction

Mammographic density is a strong risk factor for breast cancer overall, but few studies have examined the association between mammographic density and specific subtypes of breast cancer, especially aggressive basal-like breast cancers. Because basal-like breast cancers are less frequently screen-detected, it is important to understand how mammographic density relates to risk of basal-like breast cancer.

Methods

We estimated associations between mammographic density and breast cancer risk according to breast cancer subtype. Cases and controls were participants in the Carolina Breast Cancer Study (CBCS) who also had mammograms recorded in the Carolina Mammography Registry (CMR). A total of 491 cases had mammograms within five years prior to and one year after diagnosis and 528 controls had screening or diagnostic mammograms close to the dates of selection into CBCS. Mammographic density was reported to the CMR using Breast Imaging Reporting and Data System categories. The expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 1 and 2 (HER1 and HER2), and cytokeratin 5/6 (CK5/6) were assessed by immunohistochemistry and dichotomized as positive or negative, with ER+ and/or PR+, and HER2- tumors classified as luminal A and ER-, PR-, HER2-, HER1+ and/or CK5/6+ tumors classified as basal-like breast cancer. Triple negative tumors were defined as negative for ER, PR and HER2. Of the 491 cases 175 were missing information on subtypes; the remaining cases included 181 luminal A, 17 luminal B, 48 basal-like, 29 ER-/PR-/HER2+, and 41 unclassified subtypes. Odds ratios comparing each subtype to all controls and case-case odds ratios comparing mammographic density distributions in basal-like to luminal A breast cancers were estimated using logistic regression.

Results

Mammographic density was associated with increased risk of both luminal A and basal-like breast cancers, although estimates were imprecise. The magnitude of the odds ratio associated with mammographic density was not substantially different between basal-like and luminal A cancers in case–control analyses and case-case analyses (case-case OR = 1.08 (95% confidence interval: 0.30, 3.84)).

Conclusions

These results suggest that risk estimates associated with mammographic density are not distinct for separate breast cancer subtypes (basal-like/triple negative vs. luminal A breast cancers). Studies with a larger number of basal-like breast cancers are needed to confirm our findings.

Clinicopathologic and demographic evaluation of triple- negative breast cancer patients among a turkish patient population: a single center experience

BACKGROUND

To evaluate the clinicopathologic and demographic characteristics of triple-negative breast cancer (TNBC) patients and to determine differences from non-triple-negative cases.

MATERIALS AND METHODS

A detailed review of the medical records of 882 breast cancer (BC) patients was conducted to obtain information regarding age, menopausal status, height and weight at the time of diagnosis, presence of diabetes or hypertension, and pathologic characteristics of the tumor (tumor size, lymph node status, histologic grade, ER status, PR status, HER2 status, p53 mutation). Body mass index (BMI) was calculated and a value of ≥30 was considered as indicative of obesity.

RESULTS

14.9% (n=132) of the patients had TNBC. There was no difference among the patients in terms of median age, comorbid conditions and menopausal status. The proportion of medullary, tubular and mucinous carcinomas was significantly higher (15.9%) in the triple-negative (TN) group, while invasive lobular histology was more frequent (8.2%) among non-triple negative (NTN) cases (p<0.001). Grade 3 (G3) tumors were more frequent in the triple-negative group (p<0.001). The rate of p53 mutation was 44.3% in TN tumors versus 28.2% in the NTN group (p<0.001). The two groups were similar in terms of LN metastasis. In the NTN group, the rate of patients with BMI ≥30 was 53% among postmenopausal patients, while it was 36% among premenopausal women, and the difference was statistically significant (p<0.001). No significant difference was observed in terms of BMI between postmenopausal and premenopausal patients in the TN group (p=0.08).

CONCLUSIONS

TNBC rates and clinicopathologic characteristics of the Turkish patient population were consistent with the data from Europe and America. However, no relationship between obesity and TNBC was observed in our study. The association between TNBC and obesity needs to be evaluated in a larger patient population.

The impact of overweight and obesity on breast cancer: data from Switzerland, so far a country little affected by the current global obesity epidemic

This review presents results from the project "The Impact of Overweight/Obesity on Breast Cancer: data from Switzerland". Swiss data is interesting because the general female population is distinctive in two areas when compared to that of most other industrialized countries: Switzerland has comparatively low rates of overweight (22-23%) and obesity (7-8%) and has rather stable rates of overweight and obesity. The entire project comprised three major issues: (I) etiology of breast cancer (BC). There is a consistently shown association between obesity and postmenopausal BC risk in countries with high obesity prevalence rates in the literature. In our Swiss study group, however, we did not find higher rates of overweight and obesity in postmenopausal BC cases than in the general population. A possible explanation for this observation may be a curvilinear dose-response relationship between BMI and postmenopausal BC risk, so that an increased risk may only be observed in populations with a high prevalence of obese/very obese women; (II) tumor characteristics. BMI was significantly associated with tumor size; this applied not only to the cases where the tumor was found by self-detection, but also to lesions detected by radiological breast examinations. In addition, a higher BMI was positively correlated with advanced TNM stage, unfavorable grading and a higher St. Gallen risk score. No associations were observed between BMI and histological subtype, estrogen receptor status, HER2 status and triple negative BC; (III) patient compliance and persistence towards adjuvant BC therapy. Many studies found that the prognosis of overweight/obese BC patients was significantly lower than that of normal weight patients. However, failure of compliance and persistence towards therapy on the part of the patient is not a contributing factor for this observed unfavorable prognosis. In most therapy modes, patients with increasing BMI demonstrated greater motivation and perseverance towards the recommended treatment.

Clinicopathological features and prognosis of triple negative breast cancer in Kuwait: A comparative/perspective analysis

AIM

The aim of this study was to determine the incidence of TNBC in Kuwait, to analyze the clinicopathologic features and prognosis of this type of breast cancer, and compare it with reports from other regions of the world.

BACKGROUND

Triple negative breast cancer (TNBC) is defined as a subtype that is negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). There is a growing evidence of the heterogeneity of such entity on the molecular level that may cause discrete outcomes.

METHODS

We analyzed the clinicopathologic features of 363 TNBC cases which were diagnosed in Kuwait from July 1999 to June 2009. The disease-free survival (DFS) and overall survival (OS) were analyzed by Kaplan-Meier method. Comparison was done with reports from USA, Europe, Middle and Far East.

RESULTS

Among 2986 patients diagnosed with breast cancer in Kuwait, 363 patients (12.2%) were TNBC. The median age was 48 years, 57.2% had lymph nodes (LN) metastasis, 56.9% were of grade III tumor and 41.9% had stage II disease. 81% developed recurrences and 75% of deaths occurred by 2.5 years after treatment. There is marked variation of clinicopathologic features according to country of patients' cohort.

CONCLUSION

The incidence of TNBC in our study is similar to other studies. TNBC patients showed an early major recurrence surge peaking at approximately year 2.5. Regional variation of clinicopathologic features indicates a need for molecular studies to define underlying molecular features and its impact on survival.

Can molecular subtyping replace axillary nodal status as prognostic marker in breast cancer?

Subtypes are an established prognostic factor of BC in western population but its significance in Indian BC patients has not been evaluated. Thus this study provides an insight into the prognostic significance of molecular classification and its effect on the survival of BC patients in Eastern India. In this hospital based study 242 BC patients attending a Comprehensive Breast Service Clinic of a reputed institute in Eastern India and having IDC were studied over a period of 7 years (January 2007 to October 2013). Nonluminal HER-2-positive and Triple negative tumors were associated with advanced stage of disease, metastatic lymph nodes and NPI ≥5.4, whereas Luminal 1 and Luminal 2 tumors were associated with early stage, uninvolved lymph nodes and NPI <5.4. Better survival was observed for the patients with Luminal 1 [OS = 57.1 % (n = 36)] and Luminal 2 [OS = 60.0 % (n = 6)], compared to Triple negative [OS = 33.6 % (n = 38)] and nonluminal HER-2-positive tumors [OS = 32.1 % (n = 18)]. This study provided some idea about the pattern of BC on the basis of classification by molecular profiling. Our study indicated that Triple negative and nonluminal HER-2-positive tumors have reduced DFS and OS compared with luminal 1 and 2 subtypes. In our patients, Triple negative and nonluminal HER-2-positive tumors were associated with established unfavorable prognostic indicators and this reflects the data in the western literature. The results suggest that the molecular subtypes are an independent prognostic and predictive marker in Indian BC patients. Whether or not molecular subtyping of breast cancer can replace axillary lymph nodes as the standard in prognosis remains to be seen, but if molecular subtyping can provide more information than the axilla about the prognosis and treatment option, it may well be the future of prognostication.

Breast cancer screening, area deprivation, and later-stage breast cancer in Appalachia: does geography matter?

OBJECTIVE

To model the relationship of an area-based measure of a breast cancer screening and geographic area deprivation on the incidence of later stage breast cancer (LSBC) across a diverse region of Appalachia.

DATA SOURCE

Central cancer registry data (2006-2008) from three Appalachian states were linked to Medicare claims and census data.

STUDY DESIGN

Exploratory spatial analysis preceded the statistical model based on negative binomial regression to model predictors and effect modification by geographic subregions.

PRINCIPAL FINDINGS

Exploratory spatial analysis revealed geographically varying effects of area deprivation and screening on LSBC. In the negative binomial regression model, predictors of LSBC included receipt of screening, area deprivation, supply of mammography centers, and female population aged>75 years. The most deprived counties had a 3.31 times greater rate of LSBC compared to the least deprived. Effect of screening on LSBC was significantly stronger in northern Appalachia than elsewhere in the study region, found mostly for high-population counties.

CONCLUSIONS

Breast cancer screening and area deprivation are strongly associated with disparity in LBSC in Appalachia. The presence of geographically varying predictors of later stage tumors in Appalachia suggests the importance of place-based health care access and risk.