Women In Steady Exercise Research (WISER) Sister: Study design and methods

Breast cancer risk and prevention in 2024: An overview from the Breast Cancer UK - Breast Cancer Prevention Conference

The Breast Cancer UK-Breast Cancer Prevention Conference addressed risk from environmental pollutants and health behaviour-related breast-cancer risk. Epidemiological studies examining individual chemicals and breast cancer risk have produced inconclusive results including endocrine disrupting chemicals (EDCs) Bisphenol A, per- and polyfluorinated alkyl substances as well as aluminium. However, laboratory studies have shown that multiple EDCs, can work together to exhibit effects, even when combined at levels that alone are ineffective. The TEXB-α/β assay measures total estrogenic load, and studies have provided evidence of a link between multiple-chemical exposures and breast cancer. However, prospective studies using TEXB-α/β are needed to establish a causative link. There is also a need to assess real-life exposure to environmental-chemical mixtures during pregnancy, and their potential involvement in programming adverse foetal health outcomes in later life. Higher rates of breast cancer have occurred alongside increases in potentially-modifiable risk factors such as obesity. Increasing body-mass index is associated with increased risk of developing postmenopausal breast cancer, but with decreased risk of premenopausal breast cancer. In contrast, lower rates of breast cancer in Asian compared to Western populations have been linked to soya/isoflavone consumption. Risk is decreased by breastfeeding, which is in addition to the decrease in risk observed for each birth and a young first-birth. Risk is lower in those with higher levels of self-reported physical activity. Current evidence suggests breast-cancer survivors should also avoid weight gain, be physically active, and eat a healthy diet for overall health. A broad scientific perspective on breast cancer risk requires focus on both environmental exposure to chemicals and health behaviour-related risk. Research into chemical exposure needs to focus on chemical mixtures and prospective epidemiological studies in order to test the effects on breast cancer risk. Behaviour-related research needs to focus on implementation as well as deeper understanding of the mechanisms of cancer prevention.

Obesity and metabolic dysfunction correlate with background parenchymal enhancement in premenopausal women

OBJECTIVE

This study tested the hypothesis that obesity and metabolic abnormalities correlate with background parenchymal enhancement (BPE), the volume and intensity of enhancing fibroglandular breast tissue on dynamic contrast-enhanced magnetic resonance imaging.

METHODS

Participants included 59 premenopausal women at high risk of breast cancer. Obesity was defined as BMI ≥ 30 kg/m2 . Metabolic parameters included dual-energy x-ray absorptiometry-quantified body composition, plasma biomarkers of insulin resistance, adipokines, inflammation, lipids, and urinary sex hormones. BPE was assessed using computerized algorithms on dynamic contrast-enhanced magnetic resonance imaging.

RESULTS

BMI was positively correlated with BPE (r = 0.69; p < 0.001); participants with obesity had higher BPE than those without obesity (404.9 ± 189.6 vs. 261.8 ± 143.8 cm2 ; Δ: 143.1 cm2 [95% CI: 49.5-236.7]; p = 0.003). Total body fat mass (r = 0.68; p < 0.001), body fat percentage (r = 0.64; p < 0.001), visceral adipose tissue area (r = 0.65; p < 0.001), subcutaneous adipose tissue area (r = 0.60; p < 0.001), insulin (r = 0.59; p < 0.001), glucose (r = 0.35; p = 0.011), homeostatic model of insulin resistance (r = 0.62; p < 0.001), and leptin (r = 0.60; p < 0.001) were positively correlated with BPE. Adiponectin (r = -0.44; p < 0.001) was negatively correlated with BPE. Plasma biomarkers of inflammation and lipids and urinary sex hormones were not correlated with BPE.

CONCLUSIONS

In premenopausal women at high risk of breast cancer, increased BPE is associated with obesity, insulin resistance, leptin, and adiponectin.

Feasibility of a tailored home-based exercise intervention during neoadjuvant chemotherapy in breast cancer patients

PURPOSE

To evaluate the feasibility of a home-based moderate-to-vigorous intensity, phased (introduction, intermediate, maintenance), exercise prescription in breast cancer patients receiving cardiotoxic neoadjuvant chemotherapy.

METHODS

Nineteen breast cancer patients were randomized to intervention or control for the duration of chemotherapy (16-24 weeks). The intervention was one aerobic exercise session at 80-90% VO_2max for 25 min/week and 65%-75% VO_2max for ≥ 50 min/week. Adherence to the tailored home-based program was assessed by heart rate monitors. Acceptability, tolerability, feasibility, efficacy, change in VO_2max, and patient reported outcomes, safety, and clinical events were assessed.

RESULTS

25.7% of eligible women consented (acceptability). Adherence was 87.6%. Women were not able to maintain exercise intensity as chemotherapy progressed (23.7% of exercise minutes were completed at prescribed heart rate during maintenance). Efficacy of the intervention was demonstrated by maintenance of VO_2max (-1.0 ± 13.2%) compared to (-27.5 ± 7.4%) the control group. Further, during and after therapy, patients in the intervention arm reported less fatigue (control-baseline: 14.4 ± 15.9; midpoint: 19.0 ± 11.4; follow-up: 29.4 ± 20.0; intervention-baseline: 29.2 ± 24.6; midpoint: 24.6 ± 14.4; follow-up: 23.6 ± 11.9), impairment in activities (control-baseline: 13.7 ± 16.0; midpoint: 32.8 ± 17.0; follow-up: 58.6 ± 27.9; intervention-baseline: 38.7 ± 31.8; midpoint: 47.1 ± 27.5; follow-up: 47.5 ± 31.0), and pain (control-baseline: 80.8 ± 17.1; midpoint: 73.9 ± 20.7; follow-up: 50.7 ± 25.7; intervention-baseline: 68.7 ± 28.4; midpoint: 61.4 ± 22.5; follow-up: 65.3 ± 22.4). There were no differences in adverse events, treatment delays, or pathological complete response.

CONCLUSIONS

Neoadjuvant breast cancer patients maintained approximately one hour/week of moderate-intensity exercise over the course of their treatment. Further, this volume of exercise was sufficient to maintain fitness capacity and quality of life compared to the control group.

TRIAL REGISTRY

ClinicalTrials.gov Identifier: NCT03280836, prospectively registered 9/13/2017, https://clinicaltrials.gov/ct2/show/NCT03280836 .

Association of Inflammatory Diets with Inflammatory Biomarkers in Women at High Genetic Risk for Breast Cancer

Chronically elevated levels of inflammatory biomarkers may contribute to the development of cancer and diet may be an important factor in the interplay between inflammation and cancer. We examined associations between glycemic load (GL), glycemic index (GI), and adapted dietary inflammatory index (ADII) and markers of inflammation and adipokines in 135 premenopausal women at high genetic risk for breast cancer (NCT00892515). We assessed body mass index (BMI), 3-day food records, and blood biomarkers TNF-α, IL-12, CCL2, IL-10, leptin, and adiponectin. Regression models assessed associations between dietary variables and biomarkers, adjusted for caloric intake and BMI. Participants were on average 34.2 years old with mean BMI of 26.8 kg/m². Significantly higher levels of IL-10 and leptin were observed in participants with higher GI. Leptin and adiponectin were significantly associated with ADII. Leptin remained associated with ADII after adjustment for caloric intake and BMI. There were no associations between inflammatory biomarkers of interest and GL, GI, and ADII, after adjusting for caloric intake and BMI. Elevated leptin levels were observed with higher ADII independent of caloric intake and BMI. The relationship between carbohydrate quality and inflammatory potential of the diet and markers of inflammation may be modulated by leptin.

The DAMA25 Study: Feasibility of a Lifestyle Intervention Programme for Cancer Risk Reduction in Young Italian Women with Breast Cancer Family History

BACKGROUND

Diet and physical activity (PA) can modulate sporadic and possibly familial breast cancer (BC) risk. The DAMA25 study is a single-arm 12-month intervention aimed to modify dietary and PA habits in healthy young Italian women with a positive BC family history, categorized as having intermediate or high genetic risk according to NICE (National Institute for Health and Cancer Excellence) guidelines.

METHODS

Participants, aged 25-49 years, were asked to adopt a diet mainly based on plant-based foods and to increase moderate daily activities combined with 1 h/week of more intense activity. Cooking lessons, collective walks, educational sessions, brochures, booklets and online materials were implemented. Dietary, PA habits and anthropometry were collected at baseline and at the end of the intervention. Changes on dietary, lifestyle habits and anthropometry were evaluated by GLM adjusted for weight reduction counselling aimed to participant with a BMI ≥ 25, age and baseline values of each variable.

RESULTS

Out of 237 eligible women 107 (45.2%) agreed to participate and among them 98 (91.6%) completed the intervention. The adherence rate of the intervention was 77.8%. We observed a reduction in red and processed meat (p < 0.0001) and cakes consumption (p < 0.0001). Consumption of whole grain bread (p < 0.001), leafy vegetables (p = 0.01) and olive oil (p = 0.04) increased. We observed an increase in moderate (p < 0.0001) and more intense (p < 0.0001) recreational activities, an average 1.4 kg weight loss (p = 0.005), a reduction of waist circumference (p < 0.001) and fat mass (p = 0.015).

CONCLUSIONS

The DAMA25 study shows that it is feasible an intervention to improve in the short-term dietary and PA habits and anthropometry in women with high BC familial risk.

Dose-dependent effects of aerobic exercise on clinically relevant biomarkers among healthy women at high genetic risk for breast cancer: A secondary analysis of a randomized controlled study

BACKGROUND

Excess adiposity and dysregulated metabolism are associated with increased cancer risk. Triglycerides, cholesterol, glucose, insulin, HOMA-IR, and VO₂ max are robust clinical-metabolic biomarkers of overall health.

AIMS

Aerobic exercise may improve clinical-metabolic biomarkers and decrease cancer risk. This secondary analysis of the WISER Sister randomized controlled trial investigated dose-dependent effects of aerobic exercise on clinical biomarker levels in women at high genetic risk for breast cancer.

METHODS AND RESULTS

One hundred thirty-nine participants were randomized to: control (<75 min/week), low-dose (150 min/week), and high-dose (300 min/week) aerobic exercise intervention groups. Intervention adherence was assessed via heart monitor. Fasting blood draws, cardio-pulmonary tests, and demographical surveys were taken at baseline and 5 months. Triglyceride, cholesterol, glucose, insulin, and VO₂ max changes were assessed for 80 of the 122 study completers. Ninety-six percent of assayed-completers adhered to >80% of their exercise dose. A significant dose-dependent increase in VO₂ max was observed for the low-dose and high-dose groups compared to control. No intervention effects were observed for plasma biomarkers. Overweight women (BMI > 25) showed a significant decrease in insulin levels and a trend for decreased triglycerides following exercise intervention. Significant increases in VO₂ max were independent of BMI stratification.

CONCLUSION

Women at high genetic risk for breast cancer should maintain healthy weights and aerobic capacities through aerobic exercise to achieve measurable benefits on overall health. For overweight women, exercise appears to improve subclinical metabolic dysregulation. However, normal weight women were unaffected by aerobic exercise as their biomarker levels may be below the threshold for improvement. VO₂ max increases solely quantified the benefits of exercise in already healthy women at high-risk for breast cancer.

Increased Duration of Exercise Decreases Rate of Nonresponse to Exercise but May Not Decrease Risk for Cancer Mortality

INTRODUCTION

Previous studies have observed an inverse relationship between exercise and breast cancer risk. However, there is interindividual variability in response to exercise training interventions. We investigated whether increasing the dose of aerobic exercise (150 or 300 min·wk-1), while keeping intensity of exercise constant (70%-80% HRmax), decreases the number of exercise nonresponders and further decreases associated risk for cancer mortality in our study population of women genetically predisposed for breast cancer.

METHODS

Healthy premenopausal women at elevated risk of breast cancer were randomized into control (<75 min·wk-1, n = 47), low-dose exercise (150 min·wk-1, n = 39), and high-dose exercise groups (300 min·wk-1, n = 39) for approximately 6 months. We assessed 1) clinical effectiveness (CE), defined as an improvement in predicted V˙O2max of ≥1 mL·kg-1·min-1, and twice the typical error (2× TE) of V˙O2max as thresholds to classify exercise "nonresponders"; 2) CE and 2× TE relative to exercise adherence levels; and 3) related changes in V˙O2max to predicted cancer mortality risk.

RESULTS

After our 6-month intervention, we observed that 23.5% of women in the low-dose group and 5.6% of women in the high-dose group were clinical nonresponders (P = 0.04). Clinical nonresponder status was independent of adherence level. Associated reduction in risk for cancer mortality was observed among 87.2% of women in the low-dose group and 94.9% in the high-dose group (P = 0.43).

CONCLUSION

Increasing volume (not intensity) of exercise via time spent exercising significantly decreases the number of "nonresponders." True nonresponders were observed as some women did not improve their fitness capacity despite high exercise adherence levels. Lastly, it appears 150 min·wk-1 is sufficient to decrease the predicted risk of cancer mortality.

Resistance training in breast cancer patients undergoing primary treatment: a systematic review and meta-regression of exercise dosage

BACKGROUND

Exercise is recognised as an adjunct therapy for breast cancer patients; however, little is known about the resistance training dose-response. We conducted a systematic review and meta-regression to examine the resistance training dose-response (i.e., volume and intensity) in breast cancer patients undergoing primary treatment.

METHODS

Searches in MEDLINE, CINAHL, and SPORTDiscus were conducted for studies published up to November 2019. Experimental studies that evaluated resistance-based exercise interventions in women with breast cancer undergoing primary treatment were included. Information about resistance training components, average change and change per week, as well as standardised mean difference were extracted, and used for meta-regression analysis. Outcome measures were upper and lower body muscle strength and body composition.

RESULTS

10 trials were included in the systematic review and 4 trials in the dose-response analysis. Resistance training weekly prescribed volume was inversely associated with increases in upper and lower body muscle strength (r² = 98.1-100%; p = 0.009), although there was no relationship between resistance training intensity and strength gains. There was insufficient data for the dose-response analysis of body mass index, percent body fat, and lean mass.

CONCLUSION

Low volume resistance training might be a suitable exercise recommendation for breast cancer patients undergoing primary treatment producing superior benefits for muscle strength compared to higher volume training, regardless of the training intensity. Low volume resistance training may provide a conservative and appropriate approach for breast cancer patients, allowing gradual progression and modification throughout the exercise program.

Dose-dependent effect of aerobic exercise on inflammatory biomarkers in a randomized controlled trial of women at high risk of breast cancer

BACKGROUND

Increased levels of inflammation are associated with many diseases, including cancer. Physical activity can lower breast cancer risk as well as levels of inflammation. The Women In Steady Exercise Research (WISER) Sister trial was a randomized controlled trial that investigated the effects of a dosed, moderate to vigorous, aerobic exercise intervention on levels of inflammation in premenopausal women who were at high risk of developing breast cancer.

METHODS

Participants were randomized to control (<75 minutes per week; 41 patients), low-dose exercise (150 minutes per week; 38 patients), or high-dose exercise (300 minutes per week; 37 patients) groups. The 5-menstrual cycles-long, home-based treadmill exercise intervention gradually increased in minutes per week and intensity up to a maximum of 80% of the age-predicted maximum heart rate. Blood was collected at baseline and at follow-up and assayed for chemokine (C-C motif) ligand 2 (CCL2), interleukin 10 (IL-10), interleukin 12 (IL-12), and tumor necrosis factor α (TNF-α).

RESULTS

A linear dose-response relationship was observed for the proinflammatory biomarkers CCL2 (%Δ of -5.44% in the control group, -0.03% in the low-dose exercise group, and 1.54% in the high-dose exercise group), IL-12 (%Δ of -21.5% in the control group, 38.2% in the low-dose exercise group, and 25.8% in the high-dose exercise group,) and TNF-α (%Δ of -4.69% in the control group, 9.51% in the low-dose exercise group, and 15.7% in the high-dose exercise group) but not for the anti-inflammatory biomarker IL-10 (%Δ of 5.05% in the control group, 6.05% in the low-dose exercise group, and 10.6% in the high-dose exercise group). For IL-12 and TNF-α, the percentage change was significantly higher in the low-dose (IL-12: P < .001; and TNF-α: P = .01) and high-dose (IL-12: P < .001; and TNF-α: P < .001) exercise groups compared with the control group.

CONCLUSIONS

Moderate to vigorous aerobic exercise appeared to increase levels of proinflammatory biomarkers in a dose-dependent manner in a population of healthy women at high risk of developing breast cancer. The results of the current study suggest that for healthy premenopausal women, the mechanism of reduced breast cancer risk observed in physically active individuals may not be a result of reduced levels of inflammation.

Interventions for promoting habitual exercise in people living with and beyond cancer

BACKGROUND

This is an updated version of the original Cochrane Review published in the Cochrane Library 2013, Issue 9. Despite good evidence for the health benefits of regular exercise for people living with or beyond cancer, understanding how to promote sustainable exercise behaviour change in sedentary cancer survivors, particularly over the long term, is not as well understood. A large majority of people living with or recovering from cancer do not meet current exercise recommendations. Hence, reviewing the evidence on how to promote and sustain exercise behaviour is important for understanding the most effective strategies to ensure benefit in the patient population and identify research gaps.

OBJECTIVES

To assess the effects of interventions designed to promote exercise behaviour in sedentary people living with and beyond cancer and to address the following secondary questions: Which interventions are most effective in improving aerobic fitness and skeletal muscle strength and endurance? Which interventions are most effective in improving exercise behaviour amongst patients with different cancers? Which interventions are most likely to promote long-term (12 months or longer) exercise behaviour? What frequency of contact with exercise professionals and/or healthcare professionals is associated with increased exercise behaviour? What theoretical basis is most often associated with better behavioural outcomes? What behaviour change techniques (BCTs) are most often associated with increased exercise behaviour? What adverse effects are attributed to different exercise interventions?

SEARCH METHODS

We used standard methodological procedures expected by Cochrane. We updated our 2013 Cochrane systematic review by updating the searches of the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, Embase, AMED, CINAHL, PsycLIT/PsycINFO, SportDiscus and PEDro up to May 2018. We also searched the grey literature, trial registries, wrote to leading experts in the field and searched reference lists of included studies and other related recent systematic reviews.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) that compared an exercise intervention with usual care or 'waiting list' control in sedentary people over the age of 18 with a homogenous primary cancer diagnosis.

DATA COLLECTION AND ANALYSIS

In the update, review authors independently screened all titles and abstracts to identify studies that might meet the inclusion criteria, or that could not be safely excluded without assessment of the full text (e.g. when no abstract is available). We extracted data from all eligible papers with at least two members of the author team working independently (RT, LS and RG). We coded BCTs according to the CALO-RE taxonomy. Risk of bias was assessed using the Cochrane's tool for assessing risk of bias. When possible, and if appropriate, we performed a fixed-effect meta-analysis of study outcomes. If statistical heterogeneity was noted, a meta-analysis was performed using a random-effects model. For continuous outcomes (e.g. cardiorespiratory fitness), we extracted the final value, the standard deviation (SD) of the outcome of interest and the number of participants assessed at follow-up in each treatment arm, to estimate the standardised mean difference (SMD) between treatment arms. SMD was used, as investigators used heterogeneous methods to assess individual outcomes. If a meta-analysis was not possible or was not appropriate, we narratively synthesised studies. The quality of the evidence was assessed using the GRADE approach with the GRADE profiler.

MAIN RESULTS

We included 23 studies in this review, involving a total of 1372 participants (an addition of 10 studies, 724 participants from the original review); 227 full texts were screened in the update and 377 full texts were screened in the original review leaving 35 publications from a total of 23 unique studies included in the review. We planned to include all cancers, but only studies involving breast, prostate, colorectal and lung cancer met the inclusion criteria. Thirteen studies incorporated a target level of exercise that could meet current recommendations for moderate-intensity aerobic exercise (i.e.150 minutes per week); or resistance exercise (i.e. strength training exercises at least two days per week).Adherence to exercise interventions, which is crucial for understanding treatment dose, is still reported inconsistently. Eight studies reported intervention adherence of 75% or greater to an exercise prescription that met current guidelines. These studies all included a component of supervision: in our analysis of BCTs we designated these studies as 'Tier 1 trials'. Six studies reported intervention adherence of 75% or greater to an aerobic exercise goal that was less than the current guideline recommendations: in our analysis of BCTs we designated these studies as 'Tier 2 trials.' A hierarchy of BCTs was developed for Tier 1 and Tier 2 trials, with programme goal setting, setting of graded tasks and instruction of how to perform behaviour being amongst the most frequent BCTs. Despite the uncertainty surrounding adherence in some of the included studies, interventions resulted in improvements in aerobic exercise tolerance at eight to 12 weeks (SMD 0.54, 95% CI 0.37 to 0.70; 604 participants, 10 studies; low-quality evidence) versus usual care. At six months, aerobic exercise tolerance was also improved (SMD 0.56, 95% CI 0.39 to 0.72; 591 participants; 7 studies; low-quality evidence).

AUTHORS' CONCLUSIONS

Since the last version of this review, none of the new relevant studies have provided additional information to change the conclusions. We have found some improved understanding of how to encourage previously inactive cancer survivors to achieve international physical activity guidelines. Goal setting, setting of graded tasks and instruction of how to perform behaviour, feature in interventions that meet recommendations targets and report adherence of 75% or more. However, long-term follow-up data are still limited, and the majority of studies are in white women with breast cancer. There are still a considerable number of published studies with numerous and varied issues related to high risk of bias and poor reporting standards. Additionally, the meta-analyses were often graded as consisting of low- to very low-certainty evidence. A very small number of serious adverse effects were reported amongst the studies, providing reassurance exercise is safe for this population.

A pilot study on the utility of reduced urine collection frequency protocols for the assessment of reproductive hormones in adolescent girls

BACKGROUND

The objectives of this study were to assess the feasibility of and compliance to collecting urine samples in pre- and postmenarcheal girls and to determine if a less than daily collection frequency was sufficient for assessing ovarian function.

METHODS

Twenty-five postmenarcheal girls (11-17 years) collected samples using either a two or a three samples/week protocol during one menstrual cycle. Exposure and mean estrone-1-glucuronide (E1G) and pregnanediol glucuronide concentrations were calculated, and evidence of luteal activity (ELA) was evaluated. Sixteen premenarcheal girls (8-11 years) collected one sample/month for six consecutive months. Samples were analyzed for E1G concentration. Participant compliance was calculated using dates on the urine samples and paper calendars.

RESULTS

Participants collecting three samples/week were more compliant to the protocol than those collecting two samples/week (83.6%±2.6% vs. 66.8%±6.6%; p=0.034). There were no differences (p>0.10) regarding paper calendar return (81.8%±12.2% vs. 92.9%±7.1%), recording menses (55.6%±17.6% vs. 92.3%±7.7%) or sample collection (88.9%±11.1% vs. 84.6%±10.4%) between the two protocols. The average cycle length was 30.5±1.3 days and 32% of cycles had ELA. The premenarcheal girls were 100% compliant to the protocol. Only 68.8% of participants returned the paper calendar and 81.8% of those participants recorded sample collection. The average E1G concentration was 15.9±3.8 ng/mL.

CONCLUSIONS

Use of a less than daily collection frequency during one menstrual cycle in postmenarcheal, adolescent girls is feasible and provides informative data about ovarian function. Collection of one sample/month in premenarcheal girls is feasible and detects the expected low E1G concentrations. Alternate strategies to the use of a paper calendar should be considered.

The women in steady exercise research (WISER) survivor trial: The innovative transdisciplinary design of a randomized controlled trial of exercise and weight-loss interventions among breast cancer survivors with lymphedema

INTRODUCTION

Breast cancer survivors face dual challenges: long term sequelae of treatment, and risk of recurrent disease. Obesity and a sedentary lifestyle complicate both challenges. The WISER Survivor trial assessed the effects of exercise and/or weight-loss on lymphedema, biomarkers of breast cancer recurrence, and quality of life. We report on the innovative transdisciplinary design of this trial and report attrition rates.

METHODS

This one year trial randomized breast cancer survivors who had a BMI of ≥25kg/m2, were sedentary and had breast-cancer-related-lymphedema to 1) exercise (weight training and aerobic exercise) 2) weight-loss 3) exercise and weight-loss 4) or control group. Innovative aspects included: adaptation of a community-based weight training program to a largely home-based program; use of a commercial meal replacement system as part of the lifestyle modification weight-loss program; inclusion of measures of cost-effectiveness to enable economic evaluations; and alignment with a parallel mouse model for breast cancer recurrence to enable transdisciplinary research. In this model, mice bearing dormant residual tumor cells, which spontaneously relapse, were placed on a high-fat diet. Overweight animals were randomly assigned to exercise, calorie restriction, both, or control group and followed for cancer recurrence. The animal model will guide mechanistic biomarkers to be tested in the human trial.

RESULTS & DISCUSSION

351 participants were randomized; 13 experienced breast cancer recurrence during the trial. Of the 338 participants without recurrence, 83% completed the trial. The WISER Survivor trial will show the effects of exercise and weight-loss on lymphedema outcomes, biomarkers of recurrence and quality of life. NCT ClinicalTrials.gov registration #: NCT01515124.

The dose-response effects of aerobic exercise on musculoskeletal injury: a post hoc analysis of a randomized trial

In a post hoc analysis, we quantified the risk of musculoskeletal injury (MSI) associated with different volumes of aerobic exercise in a randomized trial. Premenopausal women (n = 119) were randomized to one of three groups: low-dose aerobic exercise (150 min·per week), high-dose aerobic exercise (300 min·per week) or control (usual activity) for 5 months. Compared to the control group, the risk of reporting an acute MSI increased with higher volumes of aerobic exercise, with a similar pattern observed for recurrent MSI. The risk of reporting an MSI severe enough to impair activities of daily living did not increase with higher volumes of aerobic exercise. Approximately half of MSI were causally attributed to aerobic exercise. The risk of experiencing an acute or recurrent MSI increases with higher volumes of aerobic exercise; however, the risk of experiencing an MSI severe enough to impair activities of daily living does not increase with higher volumes of aerobic exercise.

Investigation of a Lifestyle Intervention in Women at High Risk of Breast Cancer

One fourth of breast cancer can be attributed to sedentary lifestyles and being overweight or obese. This pilot study was conducted to explore whether a 6-month lifestyle intervention affected body composition and obesity-related biomarkers among women at high risk of breast cancer. Overweight/obese women at high risk of breast cancer were randomized to the control group or to the intervention. The intervention was an individually tailored, cognitive-behavioral therapy program that assists women in identifying strategies to improve their nutrition and physical activity habits with the goal of reduced adiposity. We compared changes in body composition and plasma biomarkers from baseline to 6 months. Body weight, adiposity, leptin, insulin resistance, and C-reactive protein were significantly reduced in the intervention group versus controls. No significant differences were observed in adiponectin, insulin, glucose, or interleukin-6. Our findings suggest that this intervention improves the metabolic and inflammatory profiles of overweight/obese women at risk of breast cancer.

Commercially available lifestyle modification program: randomized controlled trial addressing heart and bone health in BRCA1/2+ breast cancer survivors after risk-reducing salpingo-oophorectomy

PURPOSE

The goal of this RCT was to examine the efficacy and safety of a web-based program to improve cardiovascular and bone health outcomes, among 35 BRCA1/2+ breast cancer survivors who underwent prophylactic oophorectomy and thus experienced premature surgical menopause.

METHODS

A 12-month commercially available web-based lifestyle modification program (Precision Nutrition Coaching) was utilized. Cardiovascular fitness, dietary intake, leisure time activity, body composition, bone mineral density, bone structure, and muscle strength were assessed.

RESULTS

Average adherence to all program components was 74.8 %. Women in the intervention group maintained their cardiovascular fitness level over the 12 months (1.1 ± 7.9 %), while the control group significantly decreased fitness capacity (-4.0 ± 7.5 %). There was a significant difference between groups in percent change of whole body bone area (-0.8 ± 2.5 control and 0.5 ± 1.30 intervention). We also observed decreased BMI (-4.7 ± 6.2 %) and fat mass (-8.6 ± 12.7 %) in the intervention group due to significant concomitant decreases in caloric intake and increases in caloric expenditure. The control group demonstrated decreased caloric intake and decreased lean tissue mass.

CONCLUSIONS

In this population at high risk for detrimental cardiovascular and bone outcomes, a commercially available lifestyle intervention program mitigated a decline in cardiovascular health, improved bone health, and decreased weight through fat loss.

IMPLICATIONS FOR CANCER SURVIVORS

Precision Nutrition Coaching has shown benefit in breast cancer survivors for reduced risk of deleterious cardiovascular and bone outcomes.

The Dose-Response Effects of Aerobic Exercise on Body Composition and Breast Tissue among Women at High Risk for Breast Cancer: A Randomized Trial

Observational data indicate that behaviors that shift energetic homeostasis, such as exercise, may decrease the risk of developing breast cancer by reducing the amount of energy-dense, metabolically active adipose tissue. Between December 2008 and April 2013, we conducted a single-blind, 5-month, clinical trial that randomized premenopausal women at high risk of developing breast cancer to one of three groups: 150 min/wk of aerobic exercise (low dose), 300 min/wk of aerobic exercise (high dose), or control. Body composition was assessed using dual-energy x-ray absorptiometry. Background parenchymal enhancement (BPE) was quantified using computerized algorithms on breast dynamic contrast-enhanced MRI. Over 5 months, compared with the control group: the low-dose and high-dose groups lost -1.5 ± 0.5 and -1.3 ± 0.5 kg of body mass (linear Ptrend = 0.032); -1.5 ± 0.4 and -1.4 ± 0.3 kg of fat mass (linear Ptrend = 0.003); -1.3 ± 0.3 and -1.4 ± 0.3% of body fat (linear Ptrend < 0.001); -15.9 ± 5.4 and -26.6 ± 5.0 cm(2) of subcutaneous adipose tissue (linear Ptrend < 0.001); and -6.6 ± 1.9 and -5.0 ± 1.9 cm(2) visceral adipose tissue (nonlinear Ptrend = 0.037). For each -1 cm(2) reduction in visceral adipose tissue, BPE decreased by -3.43 ± 1.34 cm(2) (P = 0.010) and explained 9.7% of the variability in BPE. Changes in other aforementioned body composition outcomes did not significantly correlate with changes in BPE. These mechanistic data support observational evidence that shifting energetic homeostasis through exercise may alter the risk of developing breast cancer. Additional adequately powered studies are needed to confirm and expand upon our findings that changes in body composition are associated with changes in BPE. Cancer Prev Res; 9(7); 581-8. ©2016 AACR.

A randomized phase II dose-response exercise trial among colon cancer survivors: Purpose, study design, methods, and recruitment results

BACKGROUND

Observational studies indicate that higher volumes of physical activity are associated with improved disease outcomes among colon cancer survivors. The aim of this report is to describe the purpose, study design, methods, and recruitment results of the courage trial, a National Cancer Institute (NCI) sponsored, phase II, randomized, dose-response exercise trial among colon cancer survivors.

METHODS/RESULTS

The primary objective of the courage trial is to quantify the feasibility, safety, and physiologic effects of low-dose (150 min·week(-1)) and high-dose (300 min·week(-1)) moderate-intensity aerobic exercise compared to usual-care control group over six months. The exercise groups are provided with in-home treadmills and heart rate monitors. Between January and July 2015, 1433 letters were mailed using a population-based state cancer registry; 126 colon cancer survivors inquired about participation, and 39 were randomized onto the study protocol. Age was associated with inquiry about study participation (P<0.001) and randomization onto the study protocol (P<0.001). No other demographic, clinical, or geographic characteristics were associated with study inquiry or randomization. The final trial participant was randomized in August 2015. Six month endpoint data collection was completed in February 2016.

DISCUSSION

The recruitment of colon cancer survivors into an exercise trial is feasible. The findings from this trial will inform key design aspects for future phase 2 and phase 3 randomized controlled trials to examine the efficacy of exercise to improve clinical outcomes among colon cancer survivors.

Dose-response effects of aerobic exercise on estrogen among women at high risk for breast cancer: a randomized controlled trial

Medical and surgical interventions for elevated breast cancer risk (e.g., BRCA1/2 mutation, family history) focus on reducing estrogen exposure. Women at elevated risk may be interested in less aggressive approaches to risk reduction. For example, exercise might reduce estrogen, yet has fewer serious side effects and less negative impact than surgery or hormonal medications. Randomized controlled trial. Increased risk defined by risk prediction models or BRCA mutation status. Eligibility: Age 18-50, eumenorrheic, non-smokers, and body mass index (BMI) between 21 and 50 kg/m(2). 139 were randomized. Treadmill exercise: 150 or 300 min/week, five menstrual cycles. Control group maintained exercise <75 min/week.

PRIMARY OUTCOME

Area under curve (AUC) for urinary estrogen. Secondary measures: urinary progesterone, quantitative digitized breast dynamic contrast-enhanced magnetic resonance imaging background parenchymal enhancement. Mean age 34 years, mean BMI 26.8 kg/m(2). A linear dose-response relationship was observed such that every 100 min of exercise is associated with 3.6 % lower follicular phase estrogen AUC (linear trend test, p = 0.03). No changes in luteal phase estrogen or progesterone levels. There was also a dose-response effect noted: for every 100 min of exercise, there was a 9.7 % decrease in background parenchymal enhancement as measured by imaging (linear trend test, p = 0.009). Linear dose-response effect observed to reduce follicular phase estrogen exposure measured via urine and hormone sensitive breast tissue as measured by imaging. Future research should explore maintenance of effects and extent to which findings are repeatable in lower risk women. Given the high benefit to risk ratio, clinicians can inform young women at increased risk that exercise may blunt estrogen exposure while considering whether to try other preventive therapies.