Phase II prospective randomized trial of weight loss prior to radical prostatectomy

Weight loss interventions for patients with prostate cancer: a scoping review

BACKGROUND

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Scoping Review Guidelines were used to conduct a scoping review of weight loss interventions for patients with prostate cancer, with the goal to ascertain the impact of these interventions on body weight, body composition, metabolic biomarkers, and prostate cancer-related outcomes.

METHODS

Six bibliographical databases were searched. Eligible studies included articles reporting weight loss behavioral interventions with at least dietary change as an intervention component, body weight as an outcome, and interventions not solely focused on weight loss maintenance. Patients with prostate cancer of any stage were included. At least 2 independent reviewers used a data-charting form to extract study characteristics and results.

RESULTS

A total of 12 studies were included. The sample consisted predominately of White patients with prostate cancer (multiple stages) in the United States. Most interventions included both dietary and physical activity components and were delivered 1-on-1 in-person and/or by telephone. Most of the studies reported that participants experienced significant weight loss and beneficial body composition changes, with a higher proportion of studies with a longer intervention period and dose (time) reporting greater magnitude of changes in outcomes. There were mixed results regarding the interventions' impact on metabolic biomarkers and prostate cancer-related outcomes.

DISCUSSION

Understanding the impact of weight loss interventions on patients with prostate cancer is important. Studies including metabolic biomarkers, prostate cancer outcomes, and more diverse populations are needed.

Unraveling molecular interconnections and identifying potential therapeutic targets of significance in obesity-cancer link

Obesity, a global health concern, is associated with severe health issues like type 2 diabetes, heart disease, and respiratory complications. It also increases the risk of various cancers, including melanoma, endometrial, prostate, pancreatic, esophageal adenocarcinoma, colorectal carcinoma, renal adenocarcinoma, and pre-and post-menopausal breast cancer. Obesity-induced cellular changes, such as impaired CD8+ T cell function, dyslipidemia, hypercholesterolemia, insulin resistance, mild hyperglycemia, and fluctuating levels of leptin, resistin, adiponectin, and IL-6, contribute to cancer development by promoting inflammation and creating a tumor-promoting microenvironment rich in adipocytes. Adipocytes release leptin, a pro-inflammatory substance that stimulates cancer cell proliferation, inflammation, and invasion, altering the tumor cell metabolic pathway. Adiponectin, an insulin-sensitizing adipokine, is typically downregulated in obese individuals. It has antiproliferative, proapoptotic, and antiangiogenic properties, making it a potential cancer treatment. This narrative review offers a comprehensive examination of the molecular interconnections between obesity and cancer, drawing on an extensive, though non-systematic, survey of the recent literature. This approach allows us to integrate and synthesize findings from various studies, offering a cohesive perspective on emerging themes and potential therapeutic targets. The review explores the metabolic disturbances, cellular alterations, inflammatory responses, and shifts in the tumor microenvironment that contribute to the obesity-cancer link. Finally, it discusses potential therapeutic strategies aimed at disrupting these connections, offering valuable insights into future research directions and the development of targeted interventions.

A Low or High Physical Activity Level Does Not Modulate Prostate Tumor Tissue Protein Synthesis Rates

INTRODUCTION

Physical activity level has been identified as an important factor in the development and progression of various types of cancer. In this study, we determined the impact of a low versus high physical activity level on skeletal muscle, healthy prostate, and prostate tumor protein synthesis rates in vivo in prostate cancer patients.

METHODS

Thirty prostate cancer patients (age, 66 ± 5 yr; body mass index, 27.4 ± 2.9 kg·m -2 ) were randomized to a low (<4000 steps per day, n = 15) or high (>14,000 steps per day, n = 15) physical activity level for 7 d before their scheduled radical prostatectomy. Daily deuterium oxide administration was combined with the collection of plasma, skeletal muscle, nontumorous prostate, and prostate tumor tissue during the surgical procedure to determine tissue protein synthesis rates throughout the intervention period.

RESULTS

Daily step counts averaged 3610 ± 878 and 17,589 ± 4680 steps in patients subjected to the low and high physical activity levels, respectively ( P < 0.001). No differences were observed between tissue protein synthesis rates of skeletal muscle, healthy prostate, or prostate tumor between the low (1.47% ± 0.21%, 2.74% ± 0.70%, and 4.76% ± 1.23% per day, respectively) and high (1.42% ± 0.16%, 2.64% ± 0.58%, and 4.72% ± 0.80% per day, respectively) physical activity group (all P > 0.4). Tissue protein synthesis rates were nearly twofold higher in prostate tumor compared with nontumorous prostate tissue.

CONCLUSIONS

A short-term high or low physical activity level does not modulate prostate or prostate tumor protein synthesis rates in vivo in prostate cancer patients. More studies on the impact of physical activity level on tumor protein synthesis rates and tumor progression are warranted to understand the potential impact of lifestyle interventions in the prevention and treatment of cancer.

Impact of Weight Management on Obesity-Driven Biomarkers of Prostate Cancer Progression

PURPOSE

Excess body and visceral fat increase the risk of death from prostate cancer (PCa). This phase II study aimed to test whether weight reduction by > 5% total body weight counteracts obesity-driven PCa biomarkers.

MATERIALS AND METHODS

Forty men scheduled for prostatectomy were randomized into intervention (n = 20) or control (n = 20) arms. Intervention participants followed a weight management program for 4 to 16 weeks before and 6 months after surgery. Control participants received standardized educational materials. All participants attended visits at baseline, 1 week before surgery, and 6 months after surgery. Circulating immune cells, cytokines, and chemokines were evaluated. Weight loss, body composition/distribution, quality of life, and nutrition literacy were assessed. Prostate tissue samples obtained from biopsy and surgery were analyzed.

RESULTS

From baseline to surgery (mean = 5 weeks), the intervention group achieved 5.5% of weight loss (95% CI, 4%-7%). Compared to the control, the intervention also reduced insulin, total cholesterol, LDL cholesterol, leptin, leptin:adiponectin ratio, and visceral adipose tissue. The intervention group had reduced c-peptide, plasminogen-activator-inhibitor-1, and T cell count from baseline to surgery. Myeloid-derived suppressor cells were not statistically different by group. Intervention group anthropometrics improved, including visceral and overall fat loss. No prostate tissue markers changed significantly. Quality of life measures of general and emotional health improved in the intervention group. The intervention group maintained or kept losing to a net loss of 11% initial body weight (95% CI, 8%-14%) at the study end.

CONCLUSIONS

Our study demonstrated improvements in body composition, PCa biomarkers, and quality of life with a weight management intervention.

The Pathways to Prevention program: nutrition as prevention for improved cancer outcomes

Adequate nutrition is central to well-being and health and can enhance recovery during illness. Although it is well known that malnutrition, both undernutrition and overnutrition, poses an added challenge for patients with cancer diagnoses, it remains unclear when and how to intervene and if such nutritional interventions improve clinical outcomes. In July 2022, the National Institutes of Health convened a workshop to examine key questions, identify related knowledge gaps, and provide recommendations to advance understanding about the effects of nutritional interventions. Evidence presented at the workshop found substantial heterogeneity among published randomized clinical trials, with a majority rated as low quality and yielding mostly inconsistent results. Other research cited trials in limited populations that showed potential for nutritional interventions to reduce the adverse effects associated with malnutrition in people with cancer. After review of the relevant literature and expert presentations, an independent expert panel recommends baseline screening for malnutrition risk using a validated instrument following cancer diagnosis and repeated screening during and after treatment to monitor nutritional well-being. Those at risk of malnutrition should be referred to registered dietitians for more in-depth nutritional assessment and intervention. The panel emphasizes the need for further rigorous, well-defined nutritional intervention studies to evaluate the effects on symptoms and cancer-specific outcomes as well as effects of intentional weight loss before or during treatment in people with overweight or obesity. Finally, although data on intervention effectiveness are needed first, robust data collection during trials is recommended to assess cost-effectiveness and inform coverage and implementation decisions.

White adipose tissue-derived factors and prostate cancer progression: mechanisms and targets for interventions

Obesity represents an important risk factor for prostate cancer, driving more aggressive disease, chemoresistance, and increased mortality. White adipose tissue (WAT) overgrowth in obesity is central to the mechanisms that lead to these clinical observations. Adipose stromal cells (ASCs), the progenitors to mature adipocytes and other cell types in WAT, play a vital role in driving PCa aggressiveness. ASCs produce numerous factors, especially chemokines, including the chemokine CXCL12, which is involved in driving EMT and chemoresistance in PCa. A greater understanding of the impact of WAT in obesity-induced progression of PCa and the underlying mechanisms has begun to provide opportunities for developing interventional strategies for preventing or offsetting these critical events. These include weight loss regimens, therapeutic targeting of ASCs, use of calorie restriction mimetic compounds, and combinations of compounds as well as specific receptor targeting strategies.

Interventions for Improving Body Composition in Men with Prostate Cancer: A Systematic Review and Network Meta-analysis

PURPOSE

To perform a systematic review and network meta-analysis to investigate the most effective intervention for improving body composition outcomes in prostate cancer patients during or after treatment.

METHODS

A systematic search was undertaken in multiple databases from inception to December 2020. Randomized clinical trials examining the effects of exercise/physical activity and/or nutrition interventions on body composition and body weight measures in prostate cancer patients were included. The primary endpoints were both whole-body and regional fat mass and lean mass measures, with body weight and BMI as secondary outcomes. A frequentist random-effects network meta-analysis was undertaken to examine the clustering effect of intervention modalities or control groups on the outcomes of interest. The study protocol is publicly available on PROSPERO (CRD42020202339).

RESULTS

Fifty articles describing 47 trials (n = 3207) were included. Resistance training and combined resistance and aerobic exercise were the most effective interventions to reduce body fat percentage (-0.9%; 95% confidence interval [CI], -1.4% to -0.3%) and fat mass (-0.5 kg; 95% CI, -0.9 to -0.1 kg), respectively. For whole-body and regional lean mass, combined resistance and aerobic exercise + healthy diet (0.6 kg; 95% CI, 0.1 to 1.0 kg) and resistance training alone (0.7 kg, 95% CI: 0.4 to 1.0 kg) were the best intervention, respectively. A low-fat diet was the most effective for reducing body weight immediately after or at follow-up, while no intervention promoted significant reductions in BMI.

CONCLUSIONS

These results indicate that a resistance-based exercise program alone or combined with a general healthy diet are the most effective interventions for improving overall body composition in men with prostate cancer.

Obesity and prostate cancer: A narrative review

Overweight and obese men with prostate cancer are at an increased risk of disease recurrence, exacerbated treatment-related adverse effects, development of obesity-related comorbidities, earlier progression and development of metastatic disease, and higher all-cause and prostate cancer-specific mortality. The physiological mechanisms associating obesity with poor prostate cancer outcomes remain largely unknown; however, an increased inflammatory environment and metabolic irregularities associated with excess fat mass are commonly postulated. Although research is limited, fat loss strategies using exercise and nutrition programmes may slow down prostate cancer progression and improve a patient's prognosis. This review is an overview of: 1) the association between obesity and poor prostate cancer prognosis; 2) potential physiological mechanisms linking obesity and prostate cancer progression; 3) the effect of obesity on treatments for prostate cancer; and 4) the potential for weight loss strategies to improve outcomes in patients with prostate cancer.

Examining the effects of calorie restriction on testosterone concentrations in men: a systematic review and meta-analysis

CONTEXT

Testosterone concentrations decline with age, and lower testosterone concentrations are associated with several morbidities, including sexual dysfunction, obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome.

OBJECTIVE

Because dietary habits play a critical role in weight regulation and T2DM management, the aim of this systematic review and meta-analysis was to summarize and critically evaluate the evidence from randomized controlled trials to determine the effects of calorie restriction (CR) on testosterone concentrations in men.

DATA SOURCES

A literature search was conducted across 4 databases, from their inception until March 2020.

DATA EXTRACTION

The screening and data extraction were completed by 2 authors independently, and in a blinded manner, according to a priori inclusion and exclusion criteria.

DATA ANALYSIS

Of the 4198 studies identified from the initial search, 7 randomized controlled trials were included for data extraction. Significant increases in total testosterone concentrations were reported in 3 of 4 studies in which CR was examined with overweight or obese men, compared with the control groups. Significant decreases in total testosterone concentrations were reported in 2 of 3 studies in which the effects of CR were examined with normal-weight, healthy men, compared with the control groups. In all 4 studies that examined the effect of CR on sex hormone-binding globulin concentrations, the intervention significantly increased sex hormone-binding globulin concentrations compared with that of the control groups irrespective of body composition.

CONCLUSION

This systematic review and meta-analysis provide some evidence that CR affects testosterone concentrations in men and this effect depends on their body mass index. PROSPERO registration no. CRD42020173102.

Using Exercise and Nutrition to Alter Fat and Lean Mass in Men with Prostate Cancer Receiving Androgen Deprivation Therapy: A Narrative Review

Fat mass (FM) gain and lean mass (LM) loss are common side effects for patients with prostate cancer receiving androgen deprivation therapy (ADT). Excess FM has been associated with an increased risk of developing obesity-related comorbidities, exacerbating prostate cancer progression, and all-cause and cancer-specific mortality. LM is the predominant contributor to resting metabolic rate, with any loss impacting long-term weight management as well as physical function. Therefore, reducing FM and preserving LM may improve patient-reported outcomes, risk of disease progression, and ameliorate comorbidity development. In ADT-treated patients, exercise and nutrition programs can lead to improvements in quality of life and physical function; however, effects on body composition have been variable. The aim of this review was to provide a descriptive overview and critical appraisal of exercise and nutrition-based interventions in prostate cancer patients on ADT and their effect on FM and LM. Our findings are that FM gain and LM loss are side effects of ADT that could be reduced, prevented, or even reversed with the implementation of a combined exercise and nutrition program. However, the most effective combination of specific exercise and nutrition prescriptions are yet to be determined, and thus should be a focus for future studies.

Exploration of biomarkers from a pilot weight management study for men undergoing radical prostatectomy

BACKGROUND

Several biologic mechanisms, including inflammation and immune changes, have been proposed to explain the role of obesity in prostate cancer (CaP) progression. Compared to men of a healthy weight, overweight and obese men are more likely to have CaP recurrence post-prostatectomy. Obesity is related to inflammation and immune dysregulation; thus, weight loss may be an avenue to reduce inflammation and reverse these immune processes.

OBJECTIVES

This study explores the reversibility of the biological mechanisms through intentional weight loss using a comprehensive weight management program in men undergoing prostatectomy. Outcomes include blood and tissue biomarkers, microtumor environment gene expression, inflammation markers and Dietary Inflammatory Index (DII) scores.

METHODS

Twenty overweight men undergoing prostatectomy participated in this study. Fifteen men chose the intervention and 5 men chose the nonintervention group. The intervention consisted of a comprehensive weight loss program prior to prostatectomy and a weight maintenance program following surgery. Prostate tissue samples were obtained from diagnostic biopsies before the intervention and prostatectomy samples after weight loss. Blood samples and diet records were collected at baseline, pre-surgery after weight loss and at study end after weight maintenance. Immunohistochemistry and NanoString analysis were used to analyze the tissue samples. Flow cytometry was used to assess circulating immune markers. Inflammation markers were measured using Luminex panels.

RESULTS

The intervention group lost >5% body weight prior to surgery. DII scores improved during the weight loss intervention from baseline to pre-surgery (P = 0.002); and between group differences were significant (P = 0.02). DII scores were not associated with IL-6 nor hsCRP. In the intervention, CXCL12, CXCR7, and CXCR4 (C-X-C motif chemokine ligand/receptor) and Ki67 expression decreased in the prostate tissue from biopsy to surgery (P = 0.06), yet plasma CXCL12 increased during the same timeframe (P = 0.009). The downregulation of several genes (FDR<0.001) was observed in the intervention compared to the non-intervention. Changes in immune cells were not significant in either group.

CONCLUSION

This feasibility study demonstrates that in overweight men with localized CaP, weight loss alters blood, and tissue biomarkers, as well as tumor gene expression. More research is needed to determine the biological and clinical significance of these findings.

Optimising weight-loss interventions in cancer patients-A systematic review and network meta-analysis

Background

Excess weight has been associated with increased morbidity and a worse prognosis in adult patients with early-stage cancer. The optimal lifestyle interventions to optimize anthropometric measures amongst cancer patients and survivors remain inconsistent.

Objective

To conduct a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing the effects of exercise and dietary interventions alone or in combination on anthropometric measures of adult cancer patients and survivors.

Methods

A systematic search of Medline, Embase and the Cochrane Trials Registry was performed. Outcomes of interest included changes in weight, body mass index (BMI), and waist circumference. Screening and data collection were performed by two reviewers. Bayesian NMAs were performed.

Results

Overall, 98 RCTs were included; 75 were incorporated in NMAs (n = 12,199). Groups of intervention strategies included: 3 exercise interventions, 8 dietary interventions, 7 combination interventions of diet and exercise and standard care. Median intervention duration was 26 weeks. NMA suggested that diet alone (mean difference [MD] -2.25kg, 95% CrI -3.43 to -0.91kg) and combination strategies (MD -2.52kg, 95% CrI -3.54 to -1.62kg) were associated with more weight loss compared to standard care. All dietary interventions achieved a similar magnitude of weight loss (MD range from -2.03kg to -2.52kg). Both diet alone and combination strategies demonstrated greater BMI reductions versus standard care, and each of diet alone, exercise alone and combination strategies demonstrated greater reductions in waist circumference than standard care.

Conclusion

Diet and exercise alone or in combination are effective lifestyle interventions to improve anthropometric measures in cancer patients and survivors. All reputable diets appear to be similarly effective to achieve weight loss.

Feasibility of a Weight Management Program Tailored for Overweight Men with Localized Prostate Cancer - A Pilot Study

BACKGROUND

Overweight men with prostate cancer are more likely to suffer from recurrence and death following prostatectomy compared with healthy weight men. This study tested the feasibility of delivering a comprehensive program to foster weight loss before and weight maintenance after surgery in overweight men with localized prostate cancer.

METHODS

Twenty overweight men scheduled for prostatectomy elected either the intervention (n = 15) or the nonintervention (n = 5). Anthropometrics, biomarkers, diet quality, nutrition literacy, quality of life, and long-term follow-up were assessed in both groups.

RESULTS

The intervention led to 5.55 kg of weight loss including 3.88 kg of fat loss from baseline to surgery (mean = 8.3 weeks). The intervention significantly increased fiber, protein, fruit, nut, and vegetable intake; and decreased trans fats intake during weight loss. The intervention significantly reduced insulin, C-peptide, systolic blood pressure, leptin:adiponectin ratio, and visceral adiposity compared to the nonintervention. Post-surgically, weight loss was maintained. Changes in lipid profiles, nutrition literacy, and follow-up were not statistically significant in either group.

CONCLUSION

Significant weight loss (≥5%) is feasible with a coaching intervention in overweight men preparing for prostatectomy and is associated with favorable cardiometabolic effects. This study is registered under NCT02252484 (www.clinicaltrials.gov).

Effects of caloric restriction on immunosurveillance, microbiota and cancer cell phenotype: Possible implications for cancer treatment

Fasting, caloric restriction and foods or compounds mimicking the biological effects of caloric restriction, known as caloric restriction mimetics, have been associated with a lower risk of age-related diseases, including cardiovascular diseases, cancer and cognitive decline, and a longer lifespan. Reduced calorie intake has been shown to stimulate cancer immunosurveillance, reducing the migration of immunosuppressive regulatory T cells towards the tumor bulk. Autophagy stimulation via reduction of lysine acetylation, increased sensitivity to chemo- and immunotherapy, along with a reduction of insulin-like growth factor 1 and reactive oxygen species have been described as some of the major effects triggered by caloric restriction. Fasting and caloric restriction have also been shown to beneficially influence gut microbiota composition, modify host metabolism, reduce total cholesterol and triglyceride levels, lower diastolic blood pressure and elevate morning cortisol level, with beneficial modulatory effects on cardiopulmonary fitness, body fat and weight, fatigue and weakness, and general quality of life. Moreover, caloric restriction may reduce the carcinogenic and metastatic potential of cancer stem cells, which are generally considered responsible of tumor formation and relapse. Here, we reviewed in vitro and in vivo studies describing the effects of fasting, caloric restriction and some caloric restriction mimetics on immunosurveillance, gut microbiota, metabolism, and cancer stem cell growth, highlighting the molecular and cellular mechanisms underlying these effects. Additionally, studies on caloric restriction interventions in cancer patients or cancer risk subjects are discussed. Considering the promising effects associated with caloric restriction and caloric restriction mimetics, we think that controlled-randomized large clinical trials are warranted to evaluate the inclusion of these non-pharmacological approaches in clinical practice.

Biomarkers Associated With Tumor Ki67 and Cathepsin L Gene Expression in Prostate Cancer Patients Participating in a Presurgical Weight Loss Trial

Our previous presurgical weight loss trial among 40 prostate cancer patients found that rapid (but not slow) weight loss resulted in increased tumor Ki67 and Cathepsin L (CTSL) gene expression. In follow-up analyses, we strove to better understand these unexpected findings. A correlative study was undertaken by performing additional analyses [free fatty acids (FFAs), plasma CTSL, and inflammatory cytokines] on remaining pre-post intervention sera and exploring associations with extant data on tumor Ki67, body composition, physical activity (PA), and fecal microbiota. Positive associations were observed between changes in % body fat and FFAs (ρ = 0.428, p = 0.026), insulin (ρ = 0.432, p = 0.019), and Interleukin-6 (ρ = 0.411, p = 0.041). Change in Ki67 was inversely associated with change in lean mass (ρ = -0.912, p = 0.001) and change in insulin (ρ = -0.650, p = 0.042). Change in insulin was also associated with CTSL (ρ = -0.643, p = 0.024) and FFAs (ρ = -0.700, p = 0.016). Relative abundance of Bifidobacterium was associated with CTSL (ρ = 0.627, p = 0.039) and FFAs (ρ = 0.691, p = 0.019); Firmicutes was positively associated with change in PA (ρ = 0.830, p = 0.003). Contrary to hypotheses, FFAs decreased with systemic fat loss. Moreover, although glucose metabolism improved, it was inversely associated with Ki67 and CTSL. Lean mass loss was highly correlated with increased Ki67. The relationships between prostate tumor Ki67 and CTSL and weight loss associated changes in FFAs, lean mass, and fecal microbiota warrant further investigation.

Obesity, race, and long-term prostate cancer outcomes

BACKGROUND

The authors previously found that obesity was linked with prostate cancer (PC)-specific mortality (PCSM) among men who underwent radical prostatectomy (RP). Herein, in a larger RP cohort, the authors investigated whether the association between obesity and long-term PC outcomes, including PCSM, differed by race.

METHODS

Data from 5929 patients who underwent RP and were in the Shared Equal Access Regional Cancer Hospital (SEARCH) database were analyzed. Prior to RP, body mass index (BMI) was measured and recorded in the medical records. BMI was categorized as normal weight (<25 kg/m² ), overweight (25-29.9 kg/m² ), and obese (≥30 kg/m² ). The authors assessed the association between BMI and biochemical disease recurrence (BCR), castration-resistant prostate cancer (CRPC), metastasis, and PCSM, accounting for confounders.

RESULTS

Of the 5929 patients, 1983 (33%) were black, 1321 (22%) were of normal weight, 2605 (44%) were overweight, and 2003 (34%) were obese. Compared with white men, black men were younger; had higher prostate-specific antigen levels; and were more likely to have a BMI ≥30 kg/m² , seminal vesicle invasion, and positive surgical margins (all P ≤ .032). During a median follow-up of 7.4 years, a total of 1891 patients (32%) developed BCR, 181 patients (3%) developed CRPC, 259 patients (4%) had metastasis, and 135 patients (2%) had died of PC. On multivariable analysis, obesity was found to be associated with an increased risk of PCSM (hazard ratio, 1.78; 95% confidence interval, 1.04-3.04 [P = .035]). No interaction was found between BMI and race in predicting PCSM (P ≥ .88), BCR (P ≥ .81), CRPC (P ≥ .88), or metastasis (P ≥ .60). Neither overweight nor obesity was associated with risk of BCR, CRPC, or metastasis (all P ≥ .18).

CONCLUSIONS

Obese men undergoing RP at several Veterans Affairs hospitals were found to be at an increased risk of PCSM, regardless of race.

A Randomized Controlled Trial of a 6-Month Low-Carbohydrate Intervention on Disease Progression in Men with Recurrent Prostate Cancer: Carbohydrate and Prostate Study 2 (CAPS2)

PURPOSE

Both weight loss and low-carbohydrate diets (LCD) without weight loss prolong survival in prostate cancer models. Few human trials have tested weight loss or LCD on prostate cancer.

EXPERIMENTAL DESIGN

We conducted a multi-site randomized 6-month trial of LCD versus control on PSA doubling time (PSADT) in patients with prostate cancer with biochemical recurrence (BCR) after local treatment. Eligibility included body mass index (BMI) ≥ 24 kg/m² and PSADT 3 to 36 months. The LCD arm was instructed to eat [Formula: see text]20 g/carbs/day; the control arm instructed to avoid dietary changes. Primary outcome was PSADT. Secondary outcomes included weight, lipids, glucose metabolism, and diet.

RESULTS

Of 60 planned patients, the study stopped early after an interim analysis showed futility. Twenty-seven LCD and 18 control patients completed the study. At 6 months, although both arms consumed similar protein and fats, the LCD arm reduced carbohydrates intake (-117 vs. 8 g, P < 0.001) and lost weight (-12.1 vs. -0.50 kg, P < 0.001). The LCD arm reduced HDL, triglycerides, and HbA1c with no difference in total cholesterol or glucose. Mean PSADT was similar between LCD (21 months) and control (15 months, P = 0.316) arms. In a post hoc exploratory analysis accounting for prestudy PSADT, baseline PSA, primary treatment, and hemoconcentration, PSADT was significantly longer in LCD versus control (28 vs. 13 months, P = 0.021) arms. Adverse events were few, usually mild, and returned to baseline by 6 months.

CONCLUSIONS

Among BCR patients, LCD induced weight loss and metabolic benefits with acceptable safety without affecting PSADT, suggesting LCD does not adversely affect prostate cancer growth and is safe. Given exploratory findings of longer PSADT, larger studies testing LCD on disease progression are warranted.

Randomized trial of weight loss in primary breast cancer: Impact on body composition, circulating biomarkers and tumor characteristics

Obesity adversely impacts overall and cancer‐specific survival among breast cancer patients. Preclinical studies demonstrate negative energy balance inhibits cancer progression; however, feasibility and effects in patients are unknown. A two‐arm, single‐blinded, randomized controlled weight‐loss trial was undertaken presurgery among 32 overweight/obese, Stage 0–II breast cancer patients. The attention control arm (AC) received basic nutritional counseling and upper‐body progressive resistance training whereas the weight loss intervention (WLI) arm received identical guidance, plus counseling on caloric restriction and aerobic exercise to promote 0.68–0.92 kg/week weight loss. Anthropometrics, body composition, blood and survey data were collected at baseline and presurgery ∼30 days later. Tumor markers (e.g., Ki67) and gene expression were assessed on biopsy and surgical specimens; sera were analyzed for cytokines, growth and metabolic factors. Significant WLI vs. AC differences were seen in baseline‐to‐follow‐up changes in weight (−3.62 vs. −0.52 kg), %body fat (−1.3 vs. 0%), moderate‐to‐vigorous physical activity (+224 vs. +115 min/week), caloric density (−0.3 vs. 0 kcal/g), serum leptin (−12.3 vs. −4.0 ng/dl) and upregulation of tumor PI3Kinase signaling and cell cycle‐apoptosis related genes (CC‐ARG; all p‐values <0.05). Cytolytic CD56^dimNK cell expression was positively associated with weight loss; CC‐ARG increased with physical activity. Increased tumor (nuclear) TNFα and IL‐1β, CX3CL1 and CXCL1 gene expression was observed in the WLI. Tumor Ki67 did not differ between arms. Feasibility benchmarks included 80% accrual, 100% retention, no adverse effects and excellent adherence. Short‐term weight loss interventions are feasible; however, mixed effects on tumor biology suggest unclear benefit to presurgical caloric restriction, but possible benefits of physical activity.

What's new?

Obesity adversely impacts survival among breast cancer patients. Preclinical studies demonstrate negative energy balance inhibits cancer progression; however, effects in patients are unknown. This is the first randomized controlled trial to assess the impact of a pre‐surgical weight loss intervention among early‐stage breast cancer patients. Results show the effects of acute negative energy balance on tumor biology, circulating biomarkers, and quality‐of‐life. Short‐term weight loss interventions are feasible; however, mixed effects on tumor biology suggest unclear benefit to pre‐surgical caloric restriction. Such interventions may be better timed after surgical resection, though cell cycle‐apoptosis and DNA damage‐repair scores support increasing physical activity.

Diet and lifestyle considerations for patients with prostate cancer

PURPOSE

To review the literature and provide recommendations on diet and lifestyle considerations in patients with prostate cancer using evidence from randomized controlled trials (RCTs) with additional considerations based on observational evidence.

MATERIALS AND METHODS

We initiated our search on ClinicalTrials.gov combining the term "prostate cancer" with a variety of diet and lifestyle factors. We then supplemented our summary of publications from registered trials by including other publications available on Pubmed.

RESULTS

There is a well-established benefit of exercise for improving functional outcomes and pelvic floor muscle training for improving treatment-related adverse effects. Multimodality interventions that integrate several factors (e.g., low-saturated fat, plant-based, whole-food diets with exercise, and stress reduction) appear to have the most clinically significant benefit for patients with prostate cancer. Ongoing multimodality interventions are including the efficacy of implementation strategies as observed outcomes. Limited RCT evidence suggests a clinically significant benefit for guided imagery/progressive muscle relaxation, Pilates, and lycopene-rich diets and a modest benefit for green tea, qigong, massage, and avoidance of nonprescribed vitamin and mineral supplements. Observational and single arm trial evidence indicates a need for further exploration of acupuncture, coffee, cruciferous vegetables, fish, Larrea tridentata, mushrooms, and vegetable-derived fats and avoidance of eggs, dairy, poultry with skin, processed red meat, and saturated fat. Published trials suggest no benefit from hypnosis, milk thistle, pomegranate, soy, or omega-3 fatty acid supplementation.

CONCLUSIONS

Our search demonstrated that most diet and lifestyle factors identified from observational studies have limited data from RCTs. Few items have shown early evidence of benefit. The best recommendation for patients with prostate cancer is to form a habit of wellness through healthy eating, aerobic and resistance exercise, and psychological well-being. Future trial development should consider how interventions can be implemented into real world practice.