Fortifying the Treatment of Prostate Cancer with Physical Activity

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.

Impact of a ketogenic diet intervention during radiotherapy on body composition: IV. Final results of the KETOCOMP study for rectal cancer patients

BACKGROUND & AIMS

Obesity and low muscle mass are associated with worse outcomes of colorectal cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in rectal cancer patients undergoing radiotherapy.

METHODS

Patients with non-metastasized rectal cancer were allocated to either the KD (N = 24) or the SD (N = 25) group during radiotherapy. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Pathologic response in patients undergoing neoadjuvant treatment was evaluated at the time of surgery.

RESULTS

A total of 18 KD and 23 SD patients completed the study and were eligible for analysis. The SD group experienced no noteworthy changes in any body composition parameter. In contrast, patients in the KD group lost significant amounts of body weight and fat mass, averaging 0.5 and 0.65 kg/week (p < 0.0001). There was a rapid loss of intracellular water consistent with initial intramuscular glycogen and water depletion, but skeletal muscle tissue was conserved. Pathological tumor responses were somewhat greater in the KD group, with a larger mean Dworak regression grade (p = 0.072) and larger percentage of near-complete (yT0N0 or yT1N1) responses (43 versus 15%, p = 0.116) that almost reached statistical significance in intention-to-treat analysis (50% versus 14%, p = 0.018).

CONCLUSIONS

In rectal cancer patients undergoing curative radiotherapy, a KD significantly reduced body weight and fat mass while preserving skeletal muscle mass. We could demonstrate a trend for KDs contributing synergistically to pathological tumor response, a finding in line with preclinical data that warrants future confirmation in larger studies.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.

Skeletal Muscle-Adipose Tissue-Tumor Axis: Molecular Mechanisms Linking Exercise Training in Prostate Cancer

Increased visceral adiposity may influence the development of prostate cancer (PCa) aggressive tumors and cancer mortality. White adipose tissue (WAT), usually referred to as periprostatic adipose tissue (PPAT), surrounds the prostatic gland and has emerged as a potential mediator of the tumor microenvironment. Exercise training (ET) induces several adaptations in both skeletal muscle and WAT. Some of these effects are mediated by ET-induced synthesis and secretion of several proteins, known as myo- and adipokines. Together, myokines and adipokines may act in an endocrine-like manner to favor communication between skeletal muscle and WAT, as they may work together to improve whole-body metabolic health. This crosstalk may constitute a potential mechanism by which ET exerts its beneficial role in the prevention and treatment of PCa-related disorders; however, this has not yet been explored. Therefore, we reviewed the current evidence on the effects of skeletal muscle–WAT–tumor crosstalk in PCa, and the potential mediators of this process to provide a better understanding of underlying ET-related mechanisms in cancer.

Preoperative exercise interventions to optimize continence outcomes following radical prostatectomy

Urinary incontinence is a common and predictable consequence among men with localized prostate cancer who have undergone radical prostatectomy. Despite advances in the surgical technique, urinary continence recovery time remains variable. A range of surgical and patient-related risk factors contributing to urinary incontinence after radical prostatectomy have been described, including age, BMI, membranous urethral length and urethral sphincter insufficiency. Physical activity interventions incorporating aerobic exercise, resistance training and pelvic floor muscle training programmes can positively influence the return to continence in men after radical prostatectomy. Traditional approaches to improving urinary continence after radical prostatectomy have typically focused on interventions delivered during the postoperative period (rehabilitation). However, the limited efficacy of these postoperative approaches has led to a shift from the traditional reactive model of care to more comprehensive interventions incorporating exercise-based programmes that begin in the preoperative period (prehabilitation) and continue after surgery. Comprehensive prehabilitation interventions include appropriately prescribed aerobic exercise, resistance training and specific pelvic floor muscle instruction and exercise training programmes. Transperineal ultrasonography is a non-invasive and validated method for the visualization of the action of the pelvic floor musculature, providing real-time visual biofeedback to the patient during specific pelvic floor muscle instruction and training. Importantly, the waiting time before surgery can be used for the delivery of comprehensive prehabilitation exercise-based interventions to increase patient preparedness in the lead-up to surgery and optimize continence and health-related quality-of-life outcomes following radical prostatectomy.

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.

From fatigued to fit: an investigation of the impact of physical exercise in the management of radiotherapy-induced fatigue in prostate cancer patients

Aim:

The aim of this paper is to investigate the effectiveness of physical exercise in managing fatigue during radiotherapy for prostate cancer patients. It explores the impact of various physical exercise regimes and their role in the prevention and management of fatigue to help inform best practice.

Method:

A literature search was conducted on OVID Medline database with a follow-up search on google scholar to include relevant references found during the initial search. Relevant systematic reviews and randomised controlled trials (RCTs) arising from this search were reviewed.

Findings:

There is evidence to support the notion that physical exercise in all its forms is an effective and safe intervention for fatigue management for prostate cancer patients undergoing radiotherapy. Although widely studied, there is limited evidence of fatigue management strategies being clearly implemented into current radiotherapy practice for patients with prostate cancer. This information is essential to enable therapeutic radiographers to educate prostate cancer patients regarding effective exercise strategies and ensure that fatigue is managed optimally.

Conclusion:

Further research is required into the optimum physical exercise prescription to reduce radiation-induced fatigue, and standardised best practice guidelines should be developed nationally. A future move toward patient education into physical exercise and wellbeing should be a central component of the therapeutic radiographer role with specialist advice offered by review radiographers, empowering patients to become more physically active during treatment. Therapeutic radiographers have a unique opportunity to educate and promote physical exercise through a holistic wellbeing approach that aims to mitigate fatigue and improve quality of life.

Brief behavioural intervention, delivered as standard care, to support physical activity engagement in men with prostate cancer: a pilot study protocol

Introduction

Physical activity is beneficial to men with prostate cancer, but there remain barriers to fulfilling the potential of National Health Service trusts to support men with prostate cancer to be physically active. This article describes protocols for two pilot studies, each conducted in a different setting, designed to assess the potential of a behavioural intervention to affect patients’ motivation to exercise. The intervention is theory based and inspired by recent empirical observations.

Methods and analysis

The intervention consists of a 10 min talk, delivered to patients by a man with a history of prostate cancer treatment and a good experience of exercise, as part of their standard care. This talk either takes place in a preradical prostatectomy seminar (study one), or a post-treatment seminar designed to assist patients in adjusting to life after treatment (study two). Outcomes will be compared between patients attending the existing seminar format, and patients attending the novel seminar format. The two primary outcomes are: (1) differences in self-reported physical activity before and 90 days after the seminar and (2) the likelihood of the patient seeing an in-house exercise physiotherapist in those 90 days. Data on quality of life, fatigue and exercise behavioural regulations will also be captured at the same time points.

Ethics and dissemination

These two projects have been approved by internal clinical audit committees due to their focus on service improvement. Findings from these pilot studies will be presented at oncology meetings and submitted for publication in academic journals.

Making Active Surveillance a path towards health promotion: A qualitative study on prostate cancer patients' perceptions of health promotion during Active Surveillance

OBJECTIVE

Health promotion is a key aspect for health outcomes of prostate cancer (PCa) patients. However, it has been poorly explored among patients following monitoring programmes, for example Active Surveillance (AS). This study aimed to explore PCa patients' perceptions of health promotion during AS.

METHODS

An explorative qualitative research design was adopted. Four focus groups were used to collected data from 24 men enrolled in the Prostate Cancer Research International: AS (PRIAS) protocol. A thematic analysis with an inductive approach was performed.

RESULTS

Participants described promoting health during AS as challenged by mental, age-related, informational and organisational issues. It was reported as an effort to stay in the present with a positive outlook, despite the worries for the future ("the mental theme"). It was perceived as impacted by being older and having to manage physical and mental struggles related to age ("the life-course theme"). It depended, in their accounts, on obtaining reliable information and personalised education ("the educational theme"). Finally, it was related on taking responsibility on the care process ("the organisational theme").

CONCLUSION

This study suggested ways of promoting health during AS that can help healthcare professionals and organisations building a "health-promoting AS," able to improve overall health outcomes.

Tracking steps in oncology: the time is now

Purpose

Accurate evaluation of patients’ health status is a key component of the workup, treatment, and follow-up of cancer patients. Assessments by clinicians (eg, performance status, toxicity grade) and patients (eg, quality of life) play a critical role in current practice but have significant limitations. Technological advances now provide an opportunity to track a new class of objective measures of patient activity, such as daily step counts. Here, we describe recent efforts to incorporate this technology into the field of oncology.

Design

We conducted a structured literature search using MEDLINE electronic database to identify published observational studies of tracking steps in cancer patients and trials of exercise programs for cancer survivors incorporating pedometers until February 2016.

Results

Data indicate that physical activity information may supplant existing scales for the assessment of cancer patients’ functional capacity.

Conclusion

Objective activity monitoring is poised to revolutionize the way health care providers assess cancer patients at the time of diagnosis, during treatment, and in the survivorship setting.

Epidemiology and biology of physical activity and cancer recurrence

Physical activity is emerging from epidemiologic research as a lifestyle factor that may improve survival from colorectal, breast, and prostate cancers. However, there is considerably less evidence relating physical activity to cancer recurrence and the biologic mechanisms underlying this association remain unclear. Cancer patients are surviving longer than ever before, and fear of cancer recurrence is an important concern. Herein, we provide an overview of the current epidemiologic evidence relating physical activity to cancer recurrence. We review the biologic mechanisms most commonly researched in the context of physical activity and cancer outcomes, and, using the example of colorectal cancer, we explore hypothesized mechanisms through which physical activity might intervene in the colorectal recurrence pathway. Our review highlights the importance of considering pre-diagnosis and post-diagnosis activity, as well as cancer stage and timing of recurrence, in epidemiologic studies. In addition, more epidemiologic research is needed with cancer recurrence as a consistently defined outcome studied separately from survival. Future mechanistic research using randomized controlled trials, specifically those demonstrating the exercise responsiveness of hypothesized mechanisms in early stages of carcinogenesis, are needed to inform recommendations about when to exercise and to anticipate additive or synergistic effects with other preventive behaviors or treatments.

Exercise-Induced Release of Pharmacologically Active Substances and Their Relevance for Therapy of Hepatic Injury

Chronic liver disease (CLD) features constant parenchymal injury and repair together with an increasing hepatic impairment, finally leading to fibrosis and cirrhosis and a heightened risk of hepatocellular carcinoma (HCC). Closely related to the rise in obesity, the worldwide prevalence of nonalcoholic fatty liver disease, the most common form of CLD, has reached an epidemic dimension and is estimated to afflict up to 46% of the general population, including more than one out of three U.S. citizens. Up to now there is no effective drug treatment available, which is why recommendations encompass both exercise programs and changes in dietary habits. Exercise is well-known for unleashing potent anti-inflammatory effects, which can principally counteract liver inflammation and chronic low-grade inflammation. This review article summarizes the underlying mechanisms responsible for the exercise-mediated anti-inflammatory effects, illustrates the application in animal models as well as in humans, and highlights the therapeutic value when possible. Based on the available results there is no doubt that exercise can even be beneficial in an advanced stage of liver disease and it is the goal of this review article to provide evidence for the therapeutic impact on fibrosis, cirrhosis, and HCC and to assess whether exercise might be of value as adjuvant therapy in the treatment of CLD. In principle, all exercise programs carried out in these high-risk patients should be guided and observed by qualified healthcare professionals to guarantee the patients’ safety. Nevertheless, it is also necessary to additionally determine the optimal amount and intensity of exercise to maximize its value, which is why further studies are essential.

Physical Activity and Cancer Outcomes: A Precision Medicine Approach

There is increasing interest in applying a precision medicine approach to understanding exercise as a potential treatment for cancer. We aimed to inform this new approach by appraising epidemiologic literature relating postdiagnosis physical activity to cancer outcomes overall and by molecular/genetic subgroups. Across 26 studies of breast, colorectal, and prostate cancer patients, a 37% reduction was seen in risk of cancer-specific mortality, comparing the most versus the least active patients (pooled relative risk = 0.63; 95% confidence interval: 0.54-0.73). Risks of recurrence or recurrence/cancer-specific death (combined outcome) were also reduced based on fewer studies. We identified ten studies of associations between physical activity and cancer outcomes by molecular or genetic markers. Two studies showed statistically significant risk reductions in breast cancer mortality/recurrence for the most (versus least) physically active estrogen receptor-positive/progesterone receptor-positive (ER⁺/PR⁺) patients, while others showed risk reductions among ER^-PR^- and triple-negative patients. In colorectal cancer, four studies showed statistically significant risk reductions in cancer-specific mortality for patients with high (versus low) physical activity and P21 expression, P27 expression, nuclear CTNNB1^-, PTGS2 (COX-2)⁺, or IRS1 low/negative status. One prostate cancer study showed effect modification by Gleason score. As a means to enhance this evidence, future observational studies are needed that will measure physical activity objectively before and after diagnosis, use standardized definitions for outcomes, control for competing risks, assess nonlinear dose-response relations, and consider reverse causality. Ultimately, randomized controlled trials with clinical cancer outcomes and a correlative component will provide the best evidence of causality, relating exercise to cancer outcomes, overall and for molecular and genetic subgroups. Clin Cancer Res; 22(19); 4766-75. ©2016 AACR.