Does intentional weight loss reduce cancer risk?

Long-term effects of a lifestyle modification program for men with obesity delivered in German football clubs

This study examined the long-term effects of a lifestyle modification program delivered at German Bundesliga football clubs. Weekly 90-minute group sessions over 12 weeks combined health education and physical activity and were delivered by coaches affiliated with the football clubs. A total of 371 men (mean age 49.7 years [SD = 7.6]) attended 41 classes at 19 clubs in 2017 and 2018 and participated in the long-term follow-up. Primary outcome was weight-loss at follow-up with a mean observation period of 20.4 months after baseline. Measures were taken partly by research staff and partly by participants themselves. At baseline, the men had a mean weight of 111.3 kg (SD = 16.9). Three months after baseline (posttest), the men had lost a mean of 6.3 kg (95% CI: 5.7-6.9). From posttest to follow-up, growth curve model showed men lost an average of 0.8 kg (95% CI: 0.2-1.4). Weight regain from posttest to follow-up of at least 3% was observed in 75 participants (20.2%) and was associated with less improvement in vegetable consumption in an adjusted logistic regression model. The data suggest that participation in a male-only lifestyle modification program offered by German football clubs may lead to sustained weight loss, but lack of a randomized control group and drop-outs prevent generalization of the results.

Weight-centric prevention of cancer

Background

The link between excess adiposity and carcinogenesis has been well established for multiple malignancies, and cancer is one of the main contributors to obesity-related mortality. The potential role of different weight-loss interventions on cancer risk modification has been assessed, however, its clinical implications remain to be determined. In this clinical review, we present the data assessing the effect of weight loss interventions on cancer risk.

Methods

In this clinical review, we conducted a comprehensive search of relevant literature using MEDLINE, Embase, Web of Science, and Google Scholar databases for relevant studies from inception to January 20, 2024. In this clinical review, we present systematic reviews and meta-analysis, randomized clinical trials, and prospective and retrospective observational studies that address the effect of different treatment modalities for obesity in cancer risk. In addition, we incorporate the opinions from experts in the field of obesity medicine and oncology regarding the potential of weight loss as a preventative intervention for cancer.

Results

Intentional weight loss achieved through different modalities has been associated with a reduced cancer incidence. To date, the effect of weight loss on the postmenopausal women population has been more widely studied, with multiple reports indicating a protective effect of weight loss on hormone-dependent malignancies. The effect of bariatric interventions as a protective intervention for cancer has been studied extensively, showing a significant reduction in cancer incidence and mortality, however, data for the effect of bariatric surgery on certain specific types of cancer is conflicting or limited.

Conclusion

Medical nutrition therapy, exercise, antiobesity medication, and bariatric interventions, might lead to a reduction in cancer risk through weight loss-dependent and independent factors. Further evidence is needed to better determine which population might benefit the most, and the amount of weight loss required to provide a clinically significant preventative effect.

Role of body mass index and weight change in the risk of cancer: A systematic review and meta-analysis of 66 cohort studies

Background

This study was designed to evaluate the effects of body mass index (BMI) and weight change on the risk of developing cancer overall and cancer at different sites.

Methods

We searched PubMed and other databases up to July 2023 using the keywords related to 'risk', 'cancer', 'weight', 'overweight', and 'obesity'. We identified eligible studies, and the inclusion criteria encompassed cohort studies in English that focused on cancer diagnosis and included BMI or weight change as an exposure factor. Multiple authors performed data extraction and quality assessment, and statistical analyses were carried out using RevMan and R software. We used random- or fixed-effects models to calculate the pooled relative risk (RR) or hazard ratio along with 95% confidence intervals (CIs). We used the Newcastle-Ottawa Scale to assess study quality.

Results

Analysis included 66 cohort studies. Compared to underweight or normal weight, overweight or obesity was associated with an increased risk of endometrial cancer, kidney cancer, and liver cancer but a decreased risk of prostate cancer and lung cancer. Being underweight was associated with an increased risk of gastric cancer and lung cancer but not that of postmenopausal breast cancer or female reproductive cancer. In addition, weight loss of more than five kg was protective against overall cancer risk.

Conclusions

Overweight and obesity increase the risk of most cancers, and weight loss of >5 kg reduces overall cancer risk. These findings provide insights for cancer prevention and help to elucidate the mechanisms underlying cancer development.

Registration

Reviewregistry1786.

Association between weight cycling and risk of colorectal cancer: a prospective cohort study

BACKGROUND

Weight cycling is the repeated episodes manifesting intentional weight loss and subsequent unintentional weight gain. Whether the frequency and magnitude of weight cycling is associated with colorectal cancer risk independent of body mass index (BMI) remains unknown.

METHODS

Two prospective cohort studies, Nurses' Health Study I and Health Professionals Follow-up Study, followed 85,562 participants from 1992 to 2014. Participants completed a questionnaire regarding the frequency and magnitude of intentional weight loss in the past 4 years at the baseline. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard model.

RESULTS

We identified 1626 colorectal cancer cases during up to 22 years of follow-up. In the pooled analysis of HPFS and NHS, compared to non-weight cycling, moderate weight cycling (≥3 times of intentional weight loss of ≥2.3-4.4 kg) was associated with a reduced risk of colorectal cancer after adjustment for confounders, including attained BMI after weight cycling (HR = 0.82, 95% CI 0.69, 0.97). However, no significant association was observed in mild weight cyclers and in severe weight cyclers.

CONCLUSIONS

Moderate weight cycling was associated with a lower risk of colorectal cancer independent of BMI. This finding needs further studies for replication and putative biological mechanisms.

Cardiovascular health assessment in routine cancer follow-up in community settings: survivor risk awareness and perspectives

BACKGROUND

Guidelines recommend cardiovascular risk assessment and counseling for cancer survivors. For effective implementation, it is critical to understand survivor cardiovascular health (CVH) profiles and perspectives in community settings. We aimed to (1) Assess survivor CVH profiles, (2) compare self-reported and EHR-based categorization of CVH factors, and (3) describe perceptions regarding addressing CVH during oncology encounters.

METHODS

This cross-sectional analysis utilized data from an ongoing NCI Community Oncology Research Program trial of an EHR heart health tool for cancer survivors (WF-1804CD). Survivors presenting for routine care after potentially curative treatment recruited from 8 oncology practices completed a pre-visit survey, including American Heart Association Simple 7 CVH factors (classified as ideal, intermediate, or poor). Medical record abstraction ascertained CVD risk factors and cancer characteristics. Likert-type questions assessed desired discussion during oncology care.

RESULTS

Of 502 enrolled survivors (95.6% female; mean time since diagnosis = 4.2 years), most had breast cancer (79.7%). Many survivors had common cardiovascular comorbidities, including high cholesterol (48.3%), hypertension or high BP (47.8%) obesity (33.1%), and diabetes (20.5%); 30.5% of survivors received high cardiotoxicity potential cancer treatment. Less than half had ideal/non-missing levels for physical activity (48.0%), BMI (18.9%), cholesterol (17.9%), blood pressure (14.1%), healthy diet (11.0%), and glucose/ HbA1c (6.0%). While > 50% of survivors had concordant EHR-self-report categorization for smoking, BMI, and blood pressure; cholesterol, glucose, and A1C were unknown by survivors and/or missing in the EHR for most. Most survivors agreed oncology providers should talk about heart health (78.9%).

CONCLUSIONS

Tools to promote CVH discussion can fill gaps in CVH knowledge and are likely to be well-received by survivors in community settings.

TRIAL REGISTRATION

NCT03935282, Registered 10/01/2020.

Increases in BMI contribute to worsening inflammatory biomarkers related to breast cancer risk in women: a longitudinal study

BACKGROUND

Inflammatory adipokines and cytokines play a pivotal role in linking obesity and breast cancer (BC) risk in women. We investigated the longitudinal associations between BMI change and trajectories of inflammatory biomarkers related to BC risk.

METHODS

A longitudinal study was conducted among 442 Chinese women with 3-year repeated measures from 2019 to 2021. Plasma circulating inflammatory biomarkers related to BC risk, including adiponectin (ADP), resistin (RETN), soluble leptin receptor (sOB-R), insulin-like growth factor-binding protein-3 (IGFBP-3), and C-reactive protein (CRP), were examined annually. Linear mixed-effect models (LMM) were applied to investigate associations of time-varying BMI with trajectories of biomarkers. We additionally examined the modification effect of baseline BMI groups, menopausal status, and metabolic syndrome.

RESULTS

BMI was associated with increased levels of RETN, CRP, sOB-R, and decreased levels of ADP at baseline. An increasing BMI rate was significantly associated with an average 3-year increase in RETN (β = 0.019, 95% CI 0.004 to 0.034) and sOB-R (β = 0.022, 95% CI 0.009 to 0.035), as well as a decrease in ADP (β =  - 0.006, 95% CI  - 0.012 to 0.001). These associations persisted across different baseline BMI groups. An increasing BMI rate was significantly associated with an average 3-year increase in CRP levels among normal weight (β = 0.045, 95% CI 0.001 to 0.088) and overweight (β = 0.060, 95% CI 0.014 to 0.107) women. As BMI increased over time, a more remarkable decrease in ADP was observed among women with metabolic syndrome (β =  - 0.016, 95% CI - 0.029 to - 0.004) than those without metabolic syndrome at baseline.

CONCLUSIONS

A higher increase rate of BMI was associated with poorer trajectories of inflammatory biomarkers related to BC risk. Recommendations for BMI reduction may benefit BC prevention in women, particularly for those with metabolic syndrome.

Lifestyle Factors and Energy Intakes with Risks of Breast Cancer among Pre- and Post- Menopausal Women in Taiwan

Although the incidence of invasive breast cancer (BC) among women in Asian is generally lower than that in Western countries, the incidence of BC has been on the rise in the past three decades in Asian countries. This hospital-based case-control study aimed to explore the relationship between dietary and metabolic factors and BC risk in pre- and post-menopausal women. We enrolled 285 patients with newly diagnosed BC at the National Taiwan University Hospital and 297 controls from the local community and hospital staff. Before receiving anticancer therapy, all patients with BC and control participants completed a 57-question semi-quantitative Food Frequency Questionnaire. For pre-menopausal women, plant-based factor scores rich in seeds and nuts, soy, fruits, and seaweeds correlated significantly with reduced BC risks, whereas menarche occurring at <12 years of age, reduced physical activity, and high-density lipoprotein <40 mg/dL were associated with increased BC risks. For post-menopausal women, plant-based dietary factor scores were also associated with reduced risks, whereas increased body mass index and energy intake levels correlated with increased BC risks. Diets rich in plant-based dietary patterns are protective against BC risk, regardless of menopausal status. Habitual physical activity is protective against BC risk among pre-menopausal Taiwanese women. Maintaining optimal weight and caloric intake is beneficial for reducing post-menopausal BC risk.

A six-month low-carbohydrate diet high in fat does not adversely affect endothelial function or markers of low-grade inflammation in patients with type 2 diabetes: an open-label randomized controlled trial

BACKGROUND

While a low-carbohydrate diet (LCD) reduces HbA1c in patients with type 2 diabetes (T2D), the associated high intake of fat may adversely affect cardiovascular risk factors. To address this, we examined the effect of a non-calorie-restricted LCD high in fat on endothelial function and markers of low-grade inflammation in T2D over 6 months.

METHODS

In an open-label randomized controlled trial, 71 patients with T2D were randomized 2:1 to either a LCD (< 20 E% carbohydrates, 50-60 E% fat) or a control diet (50-60 E% carbohydrates, 20-30 E% fat) for six months. Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) were assessed by ultrasound in the brachial artery together with plasma interleukin-6 (IL-6) and serum high-sensitivity C-reactive protein (hsCRP) in the participants at baseline (n = 70) and after six months (n = 64).

RESULTS

The FMD and NID were unaltered in both groups after six months, and there were no between-group differences in change of either FMD (p = 0.34) or NID (p = 0.53) in response to the interventions. The circulating hsCRP and IL-6 levels decreased only in response to LCD (both p < 0.05). However, comparing changes over time with the control diet, the LCD did not reduce either IL-6 (p = 0.25) or hsCRP (p = 0.07) levels. The lack of changes in FMD and NID in response to LCD persisted after adjustment for cardiovascular risk factors.

CONCLUSION

A LCD high in fat for six months does not adversely affect endothelial function or selected markers of low-grade inflammation, which suggests that this nutritional approach does not increase the risk of cardiovascular disease. Trial registration ClinicalTrials.gov (NCT03068078).

The Impact of Bariatric Surgery on Pancreatic Cancer Risk: a Systematic Review and Meta-Analysis

A growing body of evidence suggests that bariatric surgery is associated with a reduced risk of some cancers. This meta-analysis aims to determine whether bariatric surgery affects pancreatic cancer risk. We conducted a comprehensive literature search of PubMed, Embase, and Web of Science databases. Fixed-effect models were used to estimate pooled data and presented as odds ratio (OR) and 95% confidence interval (CI). Heterogeneity was assessed using the Cochran Q test and I² test. A total of 9 cohort studies involving 1,147,473 patients were included in the analysis. The pooled OR was 0.76 (95% CI = 0.64-0.90). The Cochran Q test and I² test indicated only mild heterogeneity (P = 0.12, I² = 38%). In the subgroup analyses, the pooled OR was 0.67 (95% CI = 0.54-0.82) for North America. In the subgroup analyses by mean follow-up time, the pooled OR was 0.46 (95% CI = 0.28-0.74) for less than 5 years. In conclusion, bariatric surgery has a positive effect on pancreatic cancer reduction, especially in North America. This effect may diminish or disappear with time.

What is currently known about the association between bariatric surgery and cancer

BACKGROUND

Obesity increases the risk of multiple cancers.

OBJECTIVE

The purpose of this manuscript is to review the high-quality studies that have provided the most compelling evidence around the association between bariatric surgery and cancer risk.

SETTING

Literature review.

METHODS

The literature was reviewed for large high quality observational studies with well matched controls. Identified studies were summarized in this review.

RESULTS

Four large cohort studies were identified and summarized including the Swedish Obese Subjects study, the Utah cohorts, the Kaiser Permanente studies and the SPLENDID study. All four cohorts demonstrated a strong association between bariatric surgery and a reduction in cancer risk. Two of the cohorts showed a reduction in cancer related mortality, and two of the cohorts found a dose-response between amount of weight loss following bariatric surgery and cancer risk.

CONCLUSIONS

The evidence that bariatric surgery is associated with a reduced risk of cancer is compelling.

Obesity and breast cancer

The paper presents an analysis of the latest literature data on the problem of obesity and breast cancer (BC). This review presents modern approaches to the diagnosis of BC in obese patients, new molecular methods of breast imaging,  analyzes the features of the course of BC with obesity depending on menstrual status, molecular biological subtypes of the tumor, the mechanisms of the development of BC against the background of obesity.

Associations between circulating obesity-related biomarkers and prognosis in female breast cancer survivors: a systematic review of observational data in women enrolled in lifestyle intervention trials

Obesity plays an important role in the development and progression of breast cancer via various oncogenic pathways. However, the biological mechanisms underlying this relationship are not fully understood. Moreover, it is unclear whether obesity-related and further associated biomarkers could be suitable targets for lifestyle interventions. This systematic review was conducted to examine relationships between obesity-related blood parameters and prognosis for breast cancer survivors enrolled in lifestyle intervention studies. A systematic, computerized literature search was conducted from inception through August 26th, 2020 in PubMed, EMBASE, and CENTRAL. The focus was on observational data from randomized controlled lifestyle intervention trials investigating associations between selected baseline biomarkers, measured in remission, and breast cancer recurrence, breast cancer mortality and/or all-cause mortality. Four studies with data from 5234 women met the inclusion criteria.

Studies herein provide moderate evidence that bioavailable or serum testosterone may be positively linked to breast cancer recurrence and inversely linked to disease-free survival. Limited evidence suggests no associations with circulating estradiol or insulin levels on prognosis outcomes, whereas HDL cholesterol was inversely associated with breast cancer recurrence. For some other biomarkers, such as growth factors, adipokines, and CRP, the evidence for associations with disease prognosis was too weak to draw conclusions.

Overall, despite potential candidates, there is insufficient evidence to confirm or refute that obesity-related biomarkers and sex hormones have a prognostic value for breast cancer survival. More longitudinal studies in breast cancer survivors to examine the clinical utility of obesity-related biomarkers are needed.

Cancer and Obesity: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) provides an overview of cancer and increased body fat.

Methods

The scientific information for this CPS is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

Topics include the increased risk of cancers among patients with obesity, cancer risk factor population-attributable fractions, genetic and epigenetic links between obesity and cancer, adiposopathic and mechanistic processes accounting for increased cancer risk among patients with obesity, the role of oxidative stress, and obesity-related cancers based upon Mendelian randomization and observational studies. Other topics include nutritional and physical activity principles for patients with obesity who either have cancer or are at risk for cancer, and preventive care as it relates to cancer and obesity.

Conclusions

Obesity is the second most common preventable cause of cancer and may be the most common preventable cause of cancer among nonsmokers. This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) on cancer is one of a series of OMA CPSs designed to assist clinicians in the care of patients with the disease of obesity. Patients with obesity are at greater risk of developing certain types of cancers, and treatment of obesity may influence the risk, onset, progression, and recurrence of cancer in patients with obesity.

Association of Bariatric Surgery With Cancer Risk and Mortality in Adults With Obesity

IMPORTANCE

Obesity increases the incidence and mortality from some types of cancer, but it remains uncertain whether intentional weight loss can decrease this risk.

OBJECTIVE

To investigate whether bariatric surgery is associated with lower cancer risk and mortality in patients with obesity.

DESIGN, SETTING, AND PARTICIPANTS

In the SPLENDID (Surgical Procedures and Long-term Effectiveness in Neoplastic Disease Incidence and Death) matched cohort study, adult patients with a body mass index of 35 or greater who underwent bariatric surgery at a US health system between 2004 and 2017 were included. Patients who underwent bariatric surgery were matched 1:5 to patients who did not undergo surgery for their obesity, resulting in a total of 30 318 patients. Follow-up ended in February 2021.

EXPOSURES

Bariatric surgery (n = 5053), including Roux-en-Y gastric bypass and sleeve gastrectomy, vs nonsurgical care (n = 25 265).

MAIN OUTCOMES AND MEASURES

Multivariable Cox regression analysis estimated time to incident obesity-associated cancer (a composite of 13 cancer types as the primary end point) and cancer-related mortality.

RESULTS

The study included 30 318 patients (median age, 46 years; median body mass index, 45; 77% female; and 73% White) with a median follow-up of 6.1 years (IQR, 3.8-8.9 years). The mean between-group difference in body weight at 10 years was 24.8 kg (95% CI, 24.6-25.1 kg) or a 19.2% (95% CI, 19.1%-19.4%) greater weight loss in the bariatric surgery group. During follow-up, 96 patients in the bariatric surgery group and 780 patients in the nonsurgical control group had an incident obesity-associated cancer (incidence rate of 3.0 events vs 4.6 events, respectively, per 1000 person-years). The cumulative incidence of the primary end point at 10 years was 2.9% (95% CI, 2.2%-3.6%) in the bariatric surgery group and 4.9% (95% CI, 4.5%-5.3%) in the nonsurgical control group (absolute risk difference, 2.0% [95% CI, 1.2%-2.7%]; adjusted hazard ratio, 0.68 [95% CI, 0.53-0.87], P = .002). Cancer-related mortality occurred in 21 patients in the bariatric surgery group and 205 patients in the nonsurgical control group (incidence rate of 0.6 events vs 1.2 events, respectively, per 1000 person-years). The cumulative incidence of cancer-related mortality at 10 years was 0.8% (95% CI, 0.4%-1.2%) in the bariatric surgery group and 1.4% (95% CI, 1.1%-1.6%) in the nonsurgical control group (absolute risk difference, 0.6% [95% CI, 0.1%-1.0%]; adjusted hazard ratio, 0.52 [95% CI, 0.31-0.88], P = .01).

CONCLUSIONS AND RELEVANCE

Among adults with obesity, bariatric surgery compared with no surgery was associated with a significantly lower incidence of obesity-associated cancer and cancer-related mortality.

Benefits of weight loss programs for breast cancer survivors: a systematic reviews and meta-analysis of randomized controlled trials

BACKGROUND

Obesity and weight gain have been associated with poor disease-specific and health-related outcomes in breast cancer survivors (BCS). But the benefits of weight loss in managing BCS have not been elucidated.

OBJECTIVE

To evaluate the beneficial effects of weight loss programs in randomized controlled trials on BCS.

METHODS

We searched English databases PubMed, the Cochrane Library, EMBASE, Scopus, Web of Science, CINAHL, and Chinese databases China National Knowledge Infrastructure (CNKI), Weipu Information Chinese Periodical Service Platform (VIP), China Biomedical Literature Service System (SinoMed), and Wanfang from the inception to January 2021 and collected randomized controlled trials (RCTs) of weight loss programs for BCS. Two reviewers independently screened the literature, extracted the data, and assessed the risk of bias in the included studies. The data synthesis was performed on RevMan (version 5.3), and the publication bias was calculated with STATA (version 15.1).

RESULTS

Ten RCTs were included in the meta-analysis. The current study showed that diet and exercise interventions resulted in significant improvements in body weight (MD =  - 4.43 kg, 95%CI: - 6.23 to - 2.63, P < 0.00001), waist circumference (MD =  - 2.81 cm, 95%CI: - 4.37 to - 1.26, P = 0.004), hip circumference (MD =  - 3.01 cm, 95%CI: - 4.24 to - 1.77, P < 0.0001), body mass index (MD =  - 1.69 kg/m², 95%CI: - 2.16 to - 1.21, P < 0.00001), systolic blood pressure (MD =  - 12.12 mmHg, 95%CI: - 18.97 to - 5.27), p = 0.0005), C-reactive protein (MD =  - 1.83 mg/L, 95% CI: - 2.74 to - 0.91, p < 0.0001), body fat (MD =  - 1.19 kg, 95%CI: - 1.75 to - 0.63, P < 0.001), fat mass (MD =  - 2.29 kg, 95%CI: - 3.12 to - 1.46, P < 0.0001), and lean body mass (MD =  - 2.15 kg, 95%CI: - 3.66 to - 0.65, P = 0.005). Alternatively, compared with the effects of control interventions, weight loss programs did not affect fat-free mass, total cholesterol, low-density leptin cholesterol, glucose, insulin, and leptin (P > 0.05).

CONCLUSIONS

This review summarizes the benefits of weight loss programs for BCS. The results indicated that weight loss programs could significantly improve specific anthropometric outcomes but not affect biochemical indicators. Researchers should tailor weight loss interventions to the body fat status of BCS. Evidence to support the translation of effective weight loss intervention programs into wider-scale implementation is needed to be part of routine survivorship care.

Socioeconomic Status and Inflammation in Women with Early-stage Breast Cancer: Mediation by Body Mass Index

BACKGROUND

Breast cancer is the most common cancer among women in the US, and women of low socioeconomic status (SES) show markedly poorer outcomes than those of high SES. SES may influence health through inflammation, although links between SES and inflammatory biomarkers have not been investigated in women with breast cancer. This study tested the hypothesis that breast cancer patients of lower SES would show higher levels of inflammation than those of higher SES. BMI was examined as a mediator of this association.

METHODS

Women recently diagnosed with early-stage breast cancer (N = 194) were recruited before neoadjuvant or adjuvant therapy. Participants completed questionnaires and provided blood samples for immune assessment. SES was indexed by participants' self-reported education and annual household income, BMI was determined by height and weight measurements, and blood was assayed for inflammatory biomarkers linked with cancer outcomes: IL-6, CRP, TNF-α, and sTNF-RII. General linear models tested associations between SES and inflammation, and mediation models examined indirect effects through BMI.

RESULTS

Consistent with hypotheses, education status was associated with CRP, (F(2,185) = 4.72, p = 0.001), and sTNF-RII, (F(2,185) = 4.19, p = 0.02), such that lower education was associated with higher levels of both biomarkers. Further, BMI mediated the associations between education and CRP, (95% CIs [-0.62, -0.11; -0.76, -0.21]), sTNF-RII, (95% CIs [-0.09, -0.01; -0.10, -0.02]), and IL-6, (95% CIs [-0.32, -0.05; -0.38, -0.09]). Annual household income was not significantly associated with inflammation (ps > 0.25), and indirect effects on inflammation through BMI were not significant.

CONCLUSIONS

Lower education was associated with higher levels of inflammation in this sample, which may presage poor breast cancer-related and clinical outcomes. SES should inform the development of interventions targeting BMI and inflammation in breast cancer.

A Low-Glucose Eating Pattern Improves Biomarkers of Postmenopausal Breast Cancer Risk: An Exploratory Secondary Analysis of a Randomized Feasibility Trial

Postmenopausal breast cancer is the most common obesity-related cancer death among women in the U.S. Insulin resistance, which worsens in the setting of obesity, is associated with higher breast cancer incidence and mortality. Maladaptive eating patterns driving insulin resistance represent a key modifiable risk factor for breast cancer. Emerging evidence suggests that time-restricted feeding paradigms (TRF) improve cancer-related metabolic risk factors; however, more flexible approaches could be more feasible and effective. In this exploratory, secondary analysis, we identified participants following a low-glucose eating pattern (LGEP), defined as consuming energy when glucose levels are at or below average fasting levels, as an alternative to TRF. Results show that following an LGEP regimen for at least 40% of reported eating events improves insulin resistance (HOMA-IR) and other cancer-related serum biomarkers. The magnitude of serum biomarkers changes observed here has previously been shown to favorably modulate benign breast tissue in women with overweight and obesity who are at risk for postmenopausal breast cancer. By comparison, the observed effects of LGEP were similar to results from previously published TRF studies in similar populations. These preliminary findings support further testing of LGEP as an alternative to TRF and a postmenopausal breast cancer prevention strategy. However, results should be interpreted with caution, given the exploratory nature of analyses.

A molecular link between diabetes and breast cancer: Therapeutic potential of repurposing incretin-based therapies for breast cancer

Female breast cancer recently surpassed lung cancer and became the most commonly diagnosed cancer worldwide. As per the recent data from WHO, breast cancer accounts for one out of every 8 cancer cases diagnosed among an estimated 2.3 million new cancer cases. Breast cancer is the most prevailing cancer type among women causing the highest number of cancer-related mortality. It has been estimated that in 2020, 68,5000 women died due to this disease. Breast cancers have varying degrees of molecular heterogeneity; therefore, they are divided into various molecular clinical sub types. Recent reports suggest that type 2 diabetes (one of the common chronic diseases worldwide) is linked to the higher incidence, accelerated progression, and aggressiveness of different cancers; especially breast cancer. Breast cancer is hormone-dependent in nature and has a cross-talk with metabolism. A number of antidiabetic therapies are known to exert beneficial effects on various types of cancers, including breast cancer. However, only a few reports are available on the role of incretin-based antidiabetic therapies in cancer as a whole and in breast cancer in particular. The present review sheds light on the potential of incretin based therapies on breast cancer and explores the plausible underlying mechanisms. Additionally, we have also discussed the sub types of breast cancer as well as the intricate relationship between diabetes and breast cancer.

Investigating the Dietary Habits of Male Irish Farmers to Prevent Mortality and Morbidity

Excess mortality and morbidity among Irish farmers from non-communicable diseases (NCDs) has been linked to a range of occupational risk factors. Obesity is a key risk factor underpinning this excess burden and unhealthy eating habits are linked to overweight/obesity and to disease occurrence. This study investigated the dietary habits of a sub-group of Irish male farmers and explored how these might potentially impact on health outcomes. Cross-sectional survey research was undertaken using self-reported quantitative data, based on convenience sampling and a 24-h food re-call survey. Data were analysed using frequency and chi-square analysis. Where possible, findings were compared to national survey data for Irish males. Findings revealed that a high proportion of farmers were overweight or obese and that dietary habits consisted of low intake of fruit, vegetables, and dairy and a high intake of meat, fried and processed foods, salt, and sugary and/or salty snacks. Younger farmers reported a significantly higher intake of processed meats; however, no associations were found between age, lifestyle behaviours, and dietary habits. The findings provide a greater understanding of how dietary habits potentially contribute to poorer health outcomes among farmers and underline the need for health promotion interventions, including healthy eating campaigns, aimed at farmers.

A Cardiac Rehabilitation Program for Breast Cancer Survivors: A Feasibility Study

Purpose

The purpose of this study was to determine the feasibility and preliminary efficacy of a cardiac rehabilitation (CR) intervention in the breast cancer population.

Methods

This single-arm feasibility study evaluated a 14-week CR intervention program in breast cancer survivors. Feasibility was defined as completion of at least 30/36 sessions of the program without serious adverse events (SAE) in 80% of patients. Secondary endpoints included the change in VO2 max, cardiovascular disease (CVD) risk factors, Duke Activity Secondary Index (DASI), Brief Fatigue Inventory (BFI), and QLQ-C30. All outcomes were reported as mean change and compared using paired t-tests.

Results

A total of 25 patients were enrolled in the study. 18 patients of the 25 enrolled (72%) completed the 14 weeks program without SAE. The overall adherence to the study protocol was 60%. Of the 18 participants who did not withdraw from the program, 15 (83%) adhered to the study protocol and completed 30 or more sessions. There was a nonsignificant improvement in VO2 max (mean Δ0.5, p=0.6). The scores for DASI, BFI, and QLQ-C30 improved from baseline to posttreatment.

Conclusion

A CR intervention in breast cancer survivors had high adherence in those who were able to complete the 14-week program. The program significantly improved patient reported physical activity, fatigue, and quality of life (QoL), without significant improvement in CVD risk factors. Implications for cancer patients are that early implementation of a CR program should be considered by practitioners as it improves QoL and exercise tolerance in breast cancer survivors.

Association of weight change in young adulthood with subsequent risk of hepatocellular carcinoma: a national cohort study

Risk of hepatocellular carcinoma (HCC) in young adults might be clinically overlooked for future HCC risk. Thus, we examined the association between weight change and future risk of developing HCC in young adults. We collected a nationwide and population-based cohort data of more than 2.2 million men and women aged between 20 and 39 who were without previous cancer diagnosis and underwent two consecutive biennial national health screening between 2002 and 2005 from the National Health Insurance Service database. The individuals were categorized as weight loss (≥5.0 kg and 2.0-4.9 kg), stable weight (weight gain or loss <2.0 kg), and weight gain (2.0-4.9 kg and ≥5.0 kg) and were followed-up for incident HCC from 1 January 2006 to 31 December 2018. During 12 years of follow-up, there were 2694 HCCs in men and 306 HCCs in women. In the multivariable Cox proportional hazards model adjusted for socioeconomic, health behavior, medical characteristics, and family history, weight gain of more than 5.0 kg and between 2.0 and 4.9 kg were associated with significantly increased risk in young men [hazard ratio (HR) 1.16, 95% confidence intervals (95% CI) 1.01-1.32] and young women (HR 1.34, 95% CI 1.01-1.77), respectively. Protective association of weight loss with HCC was not observed. The association of weight gain and HCC risk was stronger in young adults with underlying liver diseases compared to those without any liver disease (Pheterogeneity < 0.001). Weight gain during young adulthood should not be clinically overlooked for future HCC risk, especially among those with underlying liver diseases.

Obesity, Cancer, and Risk Reduction with Bariatric Surgery

The prevalence of noncommunicable diseases has increased dramatically in North America and throughout the world and is expected to continue increasing in coming years. Obesity has been linked to several types of cancers and is associated with increased morbidity and mortality following cancer diagnosis. Bariatric surgery has emerged as the prominent model to evaluate the effects of intentional weight loss on cancer incidence and outcomes. Current literature, comprising prospective cohort investigations, indicates site-specific reductions in cancer risk with select bariatric procedures. Future research is required to establish evidence-based indications for bariatric surgery in the context of cancer prevention.

Obese Adipose Tissue as a Driver of Breast Cancer Growth and Development: Update and Emerging Evidence

Obesity is an established risk factor for breast cancer growth and progression. A number of advances have been made in recent years revealing new insights into this link. Early events in breast cancer development involve the neoplastic transformation of breast epithelial cells to cancer cells. In obesity, breast adipose tissue undergoes significant hormonal and inflammatory changes that create a mitogenic microenvironment. Many factors that are produced in obesity have also been shown to promote tumorigenesis. Given that breast epithelial cells are surrounded by adipose tissue, the crosstalk between the adipose compartment and breast epithelial cells is hypothesized to be a significant player in the initiation and progression of breast cancer in individuals with excess adiposity. The present review examines this crosstalk with a focus on obese breast adipose-derived estrogen, inflammatory mediators and adipokines, and how they are mechanistically linked to breast cancer risk and growth through stimulation of oxidative stress, DNA damage, and pro-oncogenic transcriptional programs. Pharmacological and lifestyle strategies targeting these factors and their downstream effects are evaluated for feasibility and efficacy in decreasing the risk of obesity-induced breast epithelial cell transformation and consequently, breast cancer development.

Influence of serum inflammatory cytokines on cytochrome P450 drug metabolising activity during breast cancer chemotherapy: a patient feasibility study

Individual response to chemotherapy in patients with breast cancer is variable. Obesity and exercise are associated with better and worse outcomes, respectively, and it is known that both impact the systemic cytokine milieu. Cytochrome P450 (CYP) enzymes are responsible for the metabolism of many chemotherapy agents, and CYP enzyme activity has been shown to be modified by inflammatory cytokines in vitro and in vivo. Cytokine-associated changes in CYP metabolism may alter chemotherapy exposure, potentially affecting treatment response and patient survival. Therefore, better understanding of these biological relationships is required. This exploratory single arm open label trial investigated changes in in vivo CYP activity in twelve women treated for stage II or III breast cancer, and demonstrated for the first time the feasibility and safety of utilising the Inje phenotyping cocktail to measure CYP activity in cancer patients receiving chemotherapy. Relative CYP activity varied between participants, particularly for CYP2C9 and CYP2D6, and changes in serum concentrations of the inflammatory cytokine monocyte chemoattractant protein 1 inversely correlated to CYP3A4 activity during chemotherapy. Future use of phenotyping cocktails in a clinical oncology setting may help guide drug dosing and improve chemotherapy outcomes.

Clinical Trial Registration: Trial was retrospectively registered to the Australia New Zealand Clinical Trial Registry (ANZCTR). ACTRN12620000832976, 21 Aug 2020, https://www.anzctr.org.au/ACTRN12620000832976.aspx.

The role and its mechanism of intermittent fasting in tumors: friend or foe?

Intermittent fasting (IF) is becoming a prevailing topic worldwide, as it can cause changes in the body’s energy metabolism processes, improve health, and affect the progression of many diseases, particularly in the circumstance of oncology. Recent research has shown that IF can alter the energy metabolism of tumor cells, thereby inhibiting tumor growth and improving antitumor immune responses. Furthermore, IF can increase cancer sensitivity to chemotherapy and radiotherapy and reduce the side effects of these traditional anticancer treatments. IF is therefore emerging as a promising approach to clinical cancer treatment. However, the balance between long-term benefits of IF compared with the harm from insufficient caloric intake is not well understood. In this article, we review the role of IF in tumorigenesis and tumor therapy, and discuss some scientific problems that remain to be clarified, which might provide some assistance in the application of IF in clinical tumor therapy.

A physical activity coaching intervention can improve and maintain physical activity and health-related outcomes in adult ambulatory hospital patients: the Healthy4U-2 randomised controlled trial

Background

The Healthy 4 U-2 study sought to evaluate the effect of a twelve-week, physical activity (PA) coaching intervention for changes and maintenance in PA, anthropometrics and health-related outcomes in adults presenting to an ambulatory hospital clinic.

Methods

One hundred and twenty insufficiently active adults were recruited from an ambulatory hospital clinic and randomised to an intervention group that received an education session and five 20-min telephone sessions of PA coaching, or to a control group that received the education session only. ActiGraph GT3X accelerometers were used to measure moderate-to-vigorous physical activity (MVPA) at baseline, post-intervention (3-months) and follow-up (9-months). Secondary outcome measures (anthropometrics, PA self-efficacy, and health-related quality of life) were also assessed at the three time points.

Results

At baseline, the mean age and body mass index of participants were 53 ± 8 years and 31 ± 4 kg/m², respectively. Relative to control, the intervention group increased objectively measured MVPA at post-intervention (p < 0.001) and 9 months follow-up (p < 0.001). At the 9-month follow-up the intervention group completed 22 min/day of MVPA (95% CI: 20 to 25 min/day), which is sufficient to meet the recommended PA guidelines. The intervention group exhibited beneficial changes in body mass (p < 0.001), waist circumference (p < 0.001), body mass index (p < 0.001), PA self-efficacy (p < 0.001), and health-related quality of life (p < 0.001) at the 9-month follow-up.

Conclusions

This study demonstrates that a low contact PA coaching intervention results in beneficial changes in PA, anthropometrics and health-related outcomes in insufficiently active adults presenting to an ambulatory care clinic. The significant beneficial changes were measured at post-intervention and the 9-month follow-up, demonstrating a maintenance effect of the intervention.

Trial registration

Prospectively registered on the Australian and New Zealand Clinical Trials Registry (ANZCTR, Trial registration number: ACTRN12619000036112.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-020-01063-x.

Intensive Weight Loss Intervention and Cancer Risk in Adults with Type 2 Diabetes: Analysis of the Look AHEAD Randomized Clinical Trial

OBJECTIVE

This study was designed to determine whether intensive lifestyle intervention (ILI) aimed at weight loss lowers cancer incidence and mortality.

METHODS

Data from the Look AHEAD trial were examined to investigate whether participants randomized to ILI designed for weight loss would have reduced overall cancer incidence, obesity-related cancer incidence, and cancer mortality, as compared with the diabetes support and education (DSE) comparison group. This analysis included 4,859 participants without a cancer diagnosis at baseline except for nonmelanoma skin cancer.

RESULTS

After a median follow-up of 11 years, 684 participants (332 in ILI and 352 in DSE) were diagnosed with cancer. The incidence rates of obesity-related cancers were 6.1 and 7.3 per 1,000 person-years in ILI and DSE, respectively, with a hazard ratio (HR) of 0.84 (95% CI: 0.68-1.04). There was no significant difference between the two groups in total cancer incidence (HR, 0.93; 95% CI: 0.80-1.08), incidence of nonobesity-related cancers (HR, 1.02; 95% CI: 0.83-1.27), or total cancer mortality (HR, 0.92; 95% CI: 0.68-1.25).

CONCLUSIONS

An ILI aimed at weight loss lowered incidence of obesity-related cancers by 16% in adults with overweight or obesity and type 2 diabetes. The study sample size likely lacked power to determine effect sizes of this magnitude and smaller.

Sustained Weight Loss and Risk of Breast Cancer in Women 50 Years and Older: A Pooled Analysis of Prospective Data

BACKGROUND

Excess body weight is an established cause of postmenopausal breast cancer, but it is unknown if weight loss reduces risk.

METHODS

Associations between weight change and risk of breast cancer were examined among women aged 50 years and older in the Pooling Project of Prospective Studies of Diet and Cancer. In 10 cohorts, weight assessed on three surveys was used to examine weight change patterns over approximately 10 years (interval 1 median = 5.2 years; interval 2 median = 4.0 years). Sustained weight loss was defined as no less than 2 kg lost in interval 1 that was not regained in interval 2. Among 180 885 women, 6930 invasive breast cancers were identified during follow-up.

RESULTS

Compared with women with stable weight (±2 kg), women with sustained weight loss had a lower risk of breast cancer. This risk reduction was linear and specific to women not using postmenopausal hormones (>2-4.5 kg lost: hazard ratio [HR] = 0.82, 95% confidence interval [CI] = 0.70 to 0.96; >4.5-<9 kg lost: HR = 0.75, 95% CI = 0.63 to 0.90; ≥9 kg lost: HR = 0.68, 95% CI = 0.50 to 0.93). Women who lost at least 9 kg and gained back some (but not all) of it were also at a lower risk of breast cancer. Other patterns of weight loss and gain over the two intervals had a similar risk of breast cancer to women with stable weight.

CONCLUSIONS

These results suggest that sustained weight loss, even modest amounts, is associated with lower breast cancer risk for women aged 50 years and older. Breast cancer prevention may be a strong weight-loss motivator for the two-thirds of American women who are overweight or obese.

Neutrophil Extracellular Traps (NETs) and Damage-Associated Molecular Patterns (DAMPs): Two Potential Targets for COVID-19 Treatment

COVID-19 is a pandemic disease caused by the new coronavirus SARS-CoV-2 that mostly affects the respiratory system. The consequent inflammation is not able to clear viruses. The persistent excessive inflammatory response can build up a clinical picture that is very difficult to manage and potentially fatal. Modulating the immune response plays a key role in fighting the disease. One of the main defence systems is the activation of neutrophils that release neutrophil extracellular traps (NETs) under the stimulus of autophagy. Various molecules can induce NETosis and autophagy; some potent activators are damage-associated molecular patterns (DAMPs) and, in particular, the high-mobility group box 1 (HMGB1). This molecule is released by damaged lung cells and can induce a robust innate immunity response. The increase in HMGB1 and NETosis could lead to sustained inflammation due to SARS-CoV-2 infection. Therefore, blocking these molecules might be useful in COVID-19 treatment and should be further studied in the context of targeted therapy.

Weighing the Risk: effects of Obesity on the Mammary Gland and Breast Cancer Risk

Obesity is a preventable risk factor for breast cancer following menopause. Regardless of menopausal status, obese women who develop breast cancer have a worsened prognosis. Breast tissue is comprised of mammary epithelial cells organized into ducts and lobules and surrounded by adipose-rich connective tissue. Studies utilizing multiple in vivo models of obesity as well as human breast tissue have contributed to our understanding of how obesity alters mammary tissue. Localized changes in mammary epithelial cell populations, elevated secretion of adipokines and angiogenic mediators, inflammation within mammary adipose tissue, and remodeling of the extracellular matrix may result in an environment conducive to breast cancer growth. Despite these significant alterations caused by obesity within breast tissue, studies have suggested that some, but not all, obesity-induced changes may be mitigated with weight loss. Here, we review our current understanding regarding the impact of obesity on the breast microenvironment, how obesity-induced changes may contribute to breast tumor progression, and the impact of weight loss on the breast microenvironment.

Intermittent Fasting: Physiological Implications on Outcomes in Mice and Men

Intermittent fasting (IF) is a widely practiced dietary method that encompasses periodic restriction of food consumption. Due to its protective benefits against metabolic diseases, aging, and cardiovascular and neurodegenerative diseases, IF continues to gain attention as a preventative and therapeutic intervention to counteract these chronic diseases. Although numerous animal studies have reported positive health benefits of IF, its feasibility and efficacy in clinical settings remain controversial. Importantly, since dietary interventions such as IF have systemic effects, thoroughly investigating the tissue-specific changes in animal models is crucial to identify IF's mechanism and evaluate its potential adverse effects in humans. As such, we will review and compare the outcomes and underlying mechanisms of IF in both animal and human studies. Moreover, the limitations of IF and inconsistencies between preclinical and clinical studies will be discussed to provide insight into the gaps between translating research from bench to bedside.

Cardiometabolic Risk Factors and Benign Gynecologic Disorders

Importance

While it has long been known that polycystic ovarian syndrome is associated with cardiometabolic risk factors (CMRFs), there is emerging evidence that other benign gynecologic conditions, such as uterine leiomyomas, endometriosis, and even hysterectomy without oophorectomy, can be associated with CMRFs. Understanding the evidence and mechanisms of these associations can lead to novel preventive and therapeutic interventions.

Objective

This article discusses the evidence and the potential mechanisms mediating the association between CMRFs and benign gynecologic disorders.

Evidence Acquisition

We reviewed PubMed, EMBASE, Scopus, and Google Scholar databases to obtain plausible clinical and biological evidence, including hormonal, immunologic, inflammatory, growth factor-related, genetic, epigenetic, atherogenic, vitamin D-related, and dietary factors.

Results

Cardiometabolic risk factors appear to contribute to uterine leiomyoma pathogenesis. For example, obesity can modulate leiomyomatous cellular proliferation and extracellular matrix deposition through hyperestrogenic states, chronic inflammation, insulin resistance, and adipokines. On the other hand, endometriosis has been shown to induce systemic inflammation, thereby increasing cardiometabolic risks, for example, through inducing atherosclerotic changes.

Conclusion and Relevance

Clinical implications of these associations are 2-fold. First, screening and early modification of CMRFs can be part of a preventive strategy for uterine leiomyomas and hysterectomy. Second, patients diagnosed with uterine leiomyomas or endometriosis can be screened and closely followed for CMRFs and cardiovascular disease.

Investigation of the association between metabolic syndrome and breast cancer patients

One of the most serious cancers among women is breast cancer. This disease is the first reason for the death of women due to cancer. Increasing breast cancer risk may associate with many factors including genetic, reproductive factors, people's lifestyle, metabolic syndrome (MS) and hormones. MS has been known as a risk factor for prostate, pancreatic, breast and colorectal cancers. The purpose of this review is to identify the relationship between MS components and breast cancer individually. This study was performed by researching electronic database references including PubMed, Google Scholar, CINAHL ProQuest, and web of science through 2019. The effect of MS with its components and breast cancer was reported in many studies. Nevertheless, a thorough understanding of the mechanisms involved remains a challenge. However, one can take several preventive measures, including a proper diet, which is one of the most important determinants of metabolic status. Also, general preventive recommendations are including reducing alcohol consumption, red meat and total fat in the diet. Moreover, increasing the consumption of vegetable and fruit reduce the proportion of MS patients to improve the outcome of breast cancer patients.

Overall and Estrogen Receptor-Positive Breast Cancer Incidences Are Decreased Following Bariatric Surgery

INTRODUCTION

Bariatric surgery treats morbid obesity resulting in long-lasting weight loss. Elevated body mass index (BMI) increases breast cancer risk. We hypothesized that patients undergoing bariatric surgery would have decreased overall and estrogen receptor (ER)-positive breast cancer incidences compared to a propensity-matched non-surgical cohort.

METHODS

The bariatric population included all female patients who underwent weight loss surgery at a single institution from 1985 to 2015. Patients from all outpatient visits were propensity score matched 1:1 with bariatric patients using BMI, comorbidities, demographics, and insurance status. The primary outcome was breast cancer incidence. Univariate analyses compared the groups.

RESULTS

A total of 4860 patients were included, with 2430 in both groups. Median follow-up time from date of surgery or morbid obesity diagnosis was 5.7 years. There were no differences in age or comorbidities aside from gastroesophageal reflux disease. Seventeen (0.7%) patients in the surgery group were subsequently diagnosed with breast cancer versus 32 (1.3%) in the non-surgery group (p = 0.03). The non-surgery group had more ER-positive tumors [4 (36.4%) vs. 22 (71.0%); p = 0.04].

CONCLUSION

Female patients who underwent bariatric surgery were less frequently diagnosed with any breast cancer and ER-positive breast cancer versus a propensity-matched cohort suggesting a possible oncologic benefit to weight loss surgery.

Impact of bariatric surgery on cancer risk reduction

Obesity is second only to tobacco as a preventable cause of cancer in the US. By multifactorial and often additive mechanisms, obesity leads to the development and promotion of 40% of the cancers diagnosed in this country, including post-menopausal breast, endometrial, colorectal, kidney, liver and pancreatic cancers, among others. Though prevention of obesity should be the ultimate goal of thoughtful and effective healthcare practices, it remains a highly prevalent condition, and morbid obesity (BMI ≥40 Kg/m²) can be refractory to lifestyle interventions in many cases. Currently bariatric surgery is an effective treatment strategy for individuals who suffer from morbid obesity or obesity with associated co-morbidities and fail to lose weight under a medically supervised diet and exercise program. The current review addresses seminal studies that have investigated the potential cancer prevention effects of bariatric surgery, demonstrating a positive impact mostly in post-menopausal breast and endometrial cancers. The controversial association between bariatric surgery and increased colorectal cancer (CRC) risk is also recognized and discussed. Finally, while bariatric surgery should not be routinely recommended as a cancer prevention strategy, it has the potential to decrease the risk for certain types of cancers as a collateral beneficial effect.

Intentional weight loss, weight cycling, and endometrial cancer risk: a systematic review and meta-analysis

PURPOSE

Weight cycling, defined as intentional weight loss followed by unintentional weight regain, may attenuate the benefit of intentional weight loss on endometrial cancer risk. We summarized the literature on intentional weight loss, weight cycling after intentional weight loss, bariatric surgery, and endometrial cancer risk.

METHODS

A systematic search was conducted using MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases published between January 2000 and November 2018. We followed Preferred Reporting Items of Systematic Reviews and Meta-analysis (PRISMA) guidelines. We qualitatively summarized studies related to intentional weight loss and weight cycling due to the inconsistent definition, and quantitatively summarized studies when bariatric surgery was the mechanism of intentional weight loss.

RESULTS

A total of 127 full-text articles were reviewed, and 13 were included (bariatric surgery n=7, self-reported intentional weight loss n=2, self-reported weight cycling n=4). Qualitative synthesis suggested that, compared with stable weight, self-reported intentional weight loss was associated with lower endometrial cancer risk (RR range 0.61-0.96), whereas self-reported weight cycling was associated with higher endometrial cancer risk (OR range 1.07-2.33). The meta-analysis yielded a 59% lower risk of endometrial cancer following bariatric surgery (OR 0.41, 95% CI 0.22 to 0.74).

CONCLUSIONS

Our findings support the notion that intentional weight loss and maintenance of a stable, healthy weight can lower endometrial cancer risk. Strategies to improve awareness and maintenance of weight loss among women with obesity are needed to reduce endometrial cancer risk.

Does Bariatric Surgery Affect the Incidence of Endometrial Cancer Development? A Systematic Review

Obesity has been linked to an increased prevalence in multiple cancers. Studies have suggested a reduction in the overall risk of cancer after bariatric surgery. We reviewed the evidence for bariatric surgery reducing the risk of endometrial cancer. Data was extracted from PubMed, EMBASE, and Medline to perform a systematic review. Thirty-one full text articles were identified from 265 abstracts. Nine observational studies were relevant to endometrial cancer. In the five controlled studies, 462 of 113,032 (0.4%) patients receiving bariatric surgery versus 11,997 of 848,864 (1.4%) controls developed endometrial cancer, odds ratio of 0.317 (95% CI 0.161 to 0.627) using random effects model (P < 0.001). Bariatric surgery seems to reduce the risk of endometrial cancer; however, more research is required.

World Cancer Research Fund International: Continuous Update Project-systematic literature review and meta-analysis of observational cohort studies on physical activity, sedentary behavior, adiposity, and weight change and breast cancer risk

PURPOSE

The purpose of the present study was to systematically review the complex associations between energy balance-related factors and breast cancer risk, for which previous evidence has suggested different associations in the life course of women and by hormone receptor (HR) status of the tumor.

METHODS

Relevant publications on adulthood physical activity, sedentary behavior, body mass index (BMI), waist and hip circumferences, waist-to-hip ratio, and weight change and pre- and postmenopausal breast cancer risk were identified in PubMed up to 30 April 2017. Random-effects meta-analyses were conducted to summarize the relative risks across studies.

RESULTS

One hundred and twenty-six observational cohort studies comprising over 22,900 premenopausal and 103,000 postmenopausal breast cancer cases were meta-analyzed. Higher physical activity was inversely associated with both pre- and postmenopausal breast cancers, whereas increased sitting time was positively associated with postmenopausal breast cancer. Although higher early adult BMI (ages 18-30 years) was inversely associated with pre- and postmenopausal breast cancers, adult weight gain and greater body adiposity increased breast cancer risk in postmenopausal women, and the increased risk was evident for HR+ but not HR- breast cancers, and among never but not current users of postmenopausal hormones. The evidence was less consistent in premenopausal women. There were no associations with adult weight gain, inverse associations with adult BMI (study baseline) and hip circumference, and non-significant associations with waist circumference and waist-to-hip ratio that were reverted to positive associations on average in studies accounting for BMI. No significant associations were observed for HR-defined premenopausal breast cancers.

CONCLUSION

Better understanding on the impact of these factors on pre- and postmenopausal breast cancers and their subtypes along the life course is needed.

Overeating, caloric restriction and breast cancer risk by pathologic subtype: the EPIGEICAM study

This study analyzes the association of excessive energy intake and caloric restriction with breast cancer (BC) risk taking into account the individual energy needs of Spanish women. We conducted a multicenter matched case-control study where 973 pairs completed lifestyle and food frequency questionnaires. Expected caloric intake was predicted from a linear regression model in controls, including calories consumed as dependent variable, basal metabolic rate as an offset and physical activity as explanatory. Overeating and caloric restriction were defined taking into account the 99% confidence interval of the predicted value. The association with BC risk, overall and by pathologic subtype, was evaluated using conditional and multinomial logistic regression models. While premenopausal women that consumed few calories (>20% below predicted) had lower BC risk (OR = 0.36; 95% CI = 0.21-0.63), postmenopausal women with an excessive intake (≥40% above predicted) showed an increased risk (OR = 2.81; 95% CI = 1.65-4.79). For every 20% increase in relative (observed/predicted) caloric intake the risk of hormone receptor positive (p-trend < 0.001) and HER2+ (p-trend = 0.015) tumours increased 13%, being this figure 7% for triple negative tumours. While high energy intake increases BC risk, caloric restriction could be protective. Moderate caloric restriction, in combination with regular physical activity, could be a good strategy for BC prevention.

Obesity and cancer risk: Emerging biological mechanisms and perspectives

Continuously rising trends in obesity-related malignancies render this disease spectrum a public health priority. Worldwide, the burden of cancer attributable to obesity, expressed as population attributable fraction, is 11.9% in men and 13.1% in women. There is convincing evidence that excess body weight is associated with an increased risk for cancer of at least 13 anatomic sites, including endometrial, esophageal, renal and pancreatic adenocarcinomas; hepatocellular carcinoma; gastric cardia cancer; meningioma; multiple myeloma; colorectal, postmenopausal breast, ovarian, gallbladder and thyroid cancers. We first synopsize current epidemiologic evidence; the obesity paradox in cancer risk and mortality; the role of weight gain and weight loss in the modulation of cancer risk; reliable somatometric indicators for obesity and cancer research; and gender differences in obesity related cancers. We critically summarize emerging biological mechanisms linking obesity to cancer encompassing insulin resistance and abnormalities of the IGF-I system and signaling; sex hormones biosynthesis and pathway; subclinical chronic low-grade inflammation and oxidative stress; alterations in adipokine pathophysiology; factors deriving from ectopic fat deposition; microenvironment and cellular perturbations including vascular perturbations, epithelial-mesenchymal transition, endoplasmic reticulum stress and migrating adipose progenitor cells; disruption of circadian rhythms; dietary nutrients; factors with potential significance such as the altered intestinal microbiome; and mechanic factors in obesity and cancer. Future perspectives regarding prevention, diagnosis and therapeutics are discussed. The aim of this review is to investigate how the interplay of these main potential mechanisms and risk factors, exerts their effects on target tissues provoking them to acquire a cancerous phenotype.

The impact of obesity and bariatric surgery on circulating and tissue biomarkers of endometrial cancer risk

Obesity is the strongest risk factor for endometrial cancer (EC). To inform targeted screening and prevention strategies, we assessed the impact of obesity and subsequent bariatric surgery-induced weight loss on endometrial morphology and molecular pathways implicated in endometrial carcinogenesis. Blood and endometrial tissue were obtained from women with class III-IV obesity (body mass index ≥40 and ≥50 kg/m2 , respectively) immediately prior to gastric bypass or sleeve gastrectomy, and at two and 12 months' follow up. The endometrium underwent pathological examination and immunohistochemistry was used to quantify proliferation (Ki-67), oncogenic signaling (PTEN, pAKT, pERK) and hormone receptor (ER, PR) expression status. Circulating biomarkers of insulin resistance, reproductive function and inflammation were also measured at each time point. Seventy-two women underwent bariatric surgery. At 12 months, the mean change in total and excess body weight was -32.7 and -62.8%, respectively. Baseline endometrial biopsies revealed neoplastic change in 10 women (14%): four had EC, six had atypical hyperplasia (AH). After bariatric surgery, most cases of AH resolved (5/6) without intervention (3/6) or with intrauterine progestin (2/6). Biomarkers of endometrial proliferation (Ki-67), oncogenic signaling (pAKT) and hormone receptor status (ER, PR) were significantly reduced, with restoration of glandular PTEN expression, at 2 and 12 months. There were reductions in circulating biomarkers of insulin resistance (HbA1c, HOMA-IR) and inflammation (hsCRP, IL-6), and increases in reproductive biomarkers (LH, FSH, SHBG). We found an unexpectedly high prevalence of occult neoplastic changes in the endometrium of women undergoing bariatric surgery. Their spontaneous reversal and accompanying down-regulation of PI3K-AKT-mTOR signaling with weight loss may have implications for screening, prevention and treatment of this disease.

Randomised controlled trial to assess the impact of a lifestyle intervention (ActWELL) in women invited to NHS breast screening

INTRODUCTION

In Scotland, the incidence of breast cancer is predicted to rise significantly in the next few decades and while there are measures to support reductions in morbidity and mortality, the breast cancer community is currently exploring preventative opportunities including supporting weight management programmes in postmenopausal women. This study aims to assess the effectiveness and cost-effectiveness of a theory-based, community delivered, minimal contact, weight management (diet, physical activity and behaviour change techniques) programme (ActWELL) in women with a body mass index (BMI) >25 kg/m² attending routine breast cancer screening appointments.

METHODS AND ANALYSIS

The study will be a four-centre, 1:1 parallel group randomised controlled trial of a 12-month weight management intervention initiated in breast cancer screening centres, delivered by trained Breast Cancer Now lifestyle coaches in community settings. The intervention programme involves two intervention meetings with coaches plus (up to) nine telephone contacts over 12 months. The programme will focus on personalised diet (including alcoholic and sugary drinks) and physical activity habits. Behaviour change techniques include self-monitoring, goal setting, implementation intentions, action and coping plans. The study has a sample size of 414 women with a BMI >25 kg/m² attending routine National Health Service breast cancer screening appointments. Measures will be taken at baseline, 12 weeks and at 12-month follow-up, complemented by qualitative interviews exploring perceived acceptability and impact on habitual behaviours. The two co-primary outcomes are mean change in measured body weight and change in physical activity between groups to 12 months. Secondary outcomes are changes in eating habits, alcohol intake, sedentary time, quality of life, waist circumference, lipid, haemoglobin A1c and insulin profiles, blood pressure and cost-effectiveness of the intervention.

ETHICS AND DISSEMINATION

The protocol has been approved by East of Scotland Research Ethics Committee (17/ES/0073). All participants provide written informed consent. Dissemination will be through peer-reviewed publication and conference presentations.

TRIAL REGISTRATION NUMBER

ISRCTN11057518; Pre-results.

Underdocumentation of Obesity by Medical Residents Highlights Challenges to Effective Obesity Care

OBJECTIVE

The goal of this study was to determine attitudes and practices of physicians in training with respect to the evaluation and treatment of obesity.

METHODS

Resident-generated admission and discharge notes of all 1,765 general medicine hospital admissions during 4 nonconsecutive months were analyzed, and any references to weight, obesity, BMI, adiposity, and body fat were identified. The full general resident cohort was then surveyed for perceptions and behaviors related to obesity.

RESULTS

Obesity was considered a highly important medical issue by 98.5% of residents; 90% correctly identified a class II obesity Stunkard phenotype, and 80% accurately calculated a BMI given height and weight in metric units. Residents overestimated inpatient obesity prevalence (estimate = 75%; actual = 35%) and the rate of obesity recording in the hospital admission note (estimate = 94%; actual = 49.5%). A BMI or current weight in the admission note or discharge summary was reported in none of the 1,765 patient records, and only 6% of the patients with obesity had obesity noted in either the inpatient admission or discharge assessment or plan.

CONCLUSIONS

Though residents recognize obesity and its clinical implications, it is underreported in the assessment of inpatients. This low level of documenting obesity and its impact on clinical care planning underscores a missed opportunity to establish appropriate referrals and initiate treatment at a clinically opportune time.