Exercise as Medicine Could Be a Chance for Early Detection and Prevention of Cardiotoxicity in Cancer Treatments: A Narrative Review.

BACKGROUND: For cancer patients, cardiovascular complications as a consequence of certain oncological therapies are the leading cause of death, apart from the cancer itself. Currently, there are no uniform guidelines for detecting subclinical cardiotoxicity. Hence, the identification of cardiotoxicity arises late in the course of myocardial dysfunction after cardiac damage has occurred already. Early detection, prevention, and treatment of these cardiotoxic effects remain a challenge; therefore, supportive strategies such as physical activity gain in importance. SUMMARY: Exercise therapy, during and after cancer therapy, is considered to be safe, feasible, and effective. While animal models show protective effects, the evidence for the benefits of physical activity on future cardiovascular outcomes in human patients caused by certain cancer treatments is still limited. Consequently, targeted exercise recommendations such as frequency, intensity, time, or type are yet unclear, and certain guidelines, specifically preventing cardiotoxicity, are nonexistent. Low cardiorespiratory fitness is strongly associated with all-cause mortality as well as cardiac dysfunction. In this context, the role of cardiorespiratory fitness as an early predictor in the detection of cardiovascular dysfunction will be discussed. KEY MESSAGE: Exercise therapy during cancer treatment could have the potential to aid in both the diagnosis and treatment of cardiovascular complications. This narrative review considers the current evidence on the impact of physical activity on cardiovascular outcomes in cancer patients and proposes, according to the present knowledge, a framework for cardioprotective exercise therapies.

Can Exercise Counteract Cancer Cachexia? A Systematic Literature Review and Meta-Analysis.

BACKGROUND: Cancer-cachexia is associated with chronic inflammation, impaired muscle metabolism and body mass loss, all of which are classical targets of physical exercise. OBJECTIVES: This systematic review and meta-analysis aimed to determine the effects of exercise on body and muscle mass in cachectic cancer hosts. DATA SOURCES: PubMed/Medline, EMBASE, CINHAL, ISI Web of Science, and Cochrane Library were searched until July 2019. STUDY SELECTION: Trials had to be randomized controlled trials or controlled trials including cancer patients or animal models with cachexia-inducing tumors. Only sole exercise interventions over at least 7 days performed in a controlled environment were included. DATA EXTRACTION: Risk of bias was assessed and a random-effects model was used to pool effect sizes by standardized mean differences (SMD). RESULTS: All eligible 20 studies were performed in rodents. Studies prescribed aerobic (n = 15), strength (n = 3) or combined training (n = 2). No statistical differences were observed for body mass and muscle weight of the gastrocnemius, soleus, and tibialis muscles between the exercise and control conditions (SMD = ‒0.05, 95%CI-0.64-0.55, P = 0.87). Exercise duration prior to tumor inoculation was a statistical moderator for changes in body mass under tumor presence (P = 0.04). LIMITATIONS: No human trials were identified. A large study heterogeneity was present, probably due to different exercise modalities and outcome reporting. CONCLUSION: Exercise does not seem to affect cancer-cachexia in rodents. However, the linear regression revealed that exercise duration prior to tumor inoculation led to reduced cachexia-severity, possibly strengthening the rationale for the use of exercise in cancer patients at cachexia risk.