Exercise capacity in long-term survivors of pediatric cancer: an analysis from the Cardiac Risk Factors in Childhood Cancer Survivors Study

Maximal Aerobic Power, Quality of Life, and Ejection Fraction in Survivors of Childhood Cancer Treated with Anthracyclines

BACKGROUND

Anthracycline-induced cardiotoxicity is a frequent complication that can occur at any stage of treatment, even in survivors.

OBJECTIVE

To determine maximum aerobic power, quality of life, and left ventricular ejection fraction in childhood cancer survivors treated with anthracyclines.

DESIGN

Cross-sectional, observational study.

METHODS

The left ventricular ejection fraction was obtained from the transthoracic echocardiogram report in the medical records. Each patient underwent a 6-minute walk test, assessment of maximum aerobic power on a cycle ergometer, and evaluation of perceived exertion using the EPInfant scale, and finally, their quality of life was evaluated using the pediatric quality of life inventory model.

RESULTS

A total of 12 patients were studied, with an average of 16.2 years of age. All patients exhibited a left ventricular ejection fraction >60%, the mean distance covered in the 6-minute walk test was 516.7 m, and the mean of the maximum aerobic power was 70 W. Low quality of life scores were obtained in the physical and psychosocial aspects. In the Pearson test, a weak correlation without statistical significance was found between all the variables studied.

CONCLUSIONS

Simultaneously with the detection of cardiotoxicity in childhood cancer survivors, it is pertinent to perform physical evaluations as physical condition and cardiotoxicity seem to be issues that are not necessarily dependent.

Surveillance cardiopulmonary exercise testing can risk-stratify childhood cancer survivors: underlying pathophysiology of poor exercise performance and possible room for improvement

BACKGROUND

Asymptomatic childhood cancer survivors (CCS) frequently show decreased exercise performance. Poor exercise performance may indicate impaired future cardiovascular health.

METHODS

Cardiopulmonary exercise testing (CPET) was performed in asymptomatic off-treatment CCS (age ≥ 10 years). Patients were divided into Normal and Poor performance groups by %predicted maximum VO2 at 80%. Both peak and submaximal CPET values were analyzed.

RESULTS

Thirty-eight males (19 Normal, 19 Poor) and 40 females (18 Normal, 22 Poor) were studied. Total anthracycline dosage was comparable among 4 groups. The body mass index (BMI), although normal, and weight were significantly higher in Poor groups. Peak heart rate (HR) and peak respiratory exchange ratio (RER) were comparable in all four groups. Peak work rate (pWR)/kg, peak oxygen consumption (pVO2)/kg, peak oxygen pulse (pOP)/kg, and ventilatory anaerobic threshold (VAT)/kg were significantly lower, whereas heart rate (HR) increase by WR/kg (ΔHR/Δ[WR/kg] was significantly higher in Poor groups. Simultaneously plotting of weight & pVO2 and ΔHR/ΔWR & ΔVO2/ΔHR revealed a distinct difference between the Normal and Poor groups in both sexes, suggesting decreased skeletal muscle mass and decreased stroke volume reserve, respectively, in Poor CCS. The relationship between VAT and pVO2 was almost identical between the two groups in both sexes. Ventilatory efficiency was mildly diminished in the Poor groups.

CONCLUSIONS

Decreased skeletal muscle mass, decreased stroke volume reserve, and slightly decreased ventilatory efficiency characterize Poor CCS in both sexes. This unique combined CPET analysis provides useful clinical biomarkers to screen subclinical cardiovascular abnormality in CCS and identifies an area for improvement.

Design and methods of a randomized telehealth-based intervention to improve fitness in survivors of childhood cancer with exercise intolerance

BACKGROUND

Exercise intolerance among childhood cancer survivors substantially increases risk for early mortality, reduced cognitive function, poor quality of life, emotional distress, and sub-optimal participation in social roles. Fortunately, exercise intolerance is modifiable, even among individuals with impaired cardiopulmonary and neuromuscular health. This study aims to evaluate the impact of tailored exercise intervention remotely supervised by fitness professionals in survivors with exercise intolerance. Telehealth-based delivery of the intervention aims to enhance uptake by removing the burden of travel and allowing participants to gain confidence with exercise and physical activity at home.

METHODS

This is an ongoing single-blind, two-arm, prospective, clinical trial that will randomize 160 participants 1:1 to intervention (n = 80) and attention control (n = 80) groups. The intervention group receives an individually tailored exercise prescription based on results from baseline assessments performed remotely via a Health Insurance Portability and Accountability Act-compliant virtual platform and personal preferences for aerobic exercise. Each prescription includes aerobic and strengthening components designed to progress gradually to 150-300-min of moderate aerobic activity and twice weekly strengthening exercises over 20-weeks. The first two weeks are supervised for 6 sessions, tapering to twice/week for weeks 3-4, once/week for weeks 5-8, every other week for weeks 9-16 and once midway between weeks 17-20. The schedule is modifiable depending on participant need, adherence, and response to exercise. Each session is approximately one hour.

CONCLUSION

This study tests the efficacy of an individually prescribed, virtually supervised exercise intervention on exercise intolerant childhood cancer survivors.

CLINICALTRIALS

gov registration: NCT04714840.

Predictors of lower exercise capacity in patients with cancer

Maintaining cancer patients' exercise capacity and therefore patients' ability to live a self-determined life is of huge importance, but little is known about major determinants. We sought to identify determinants of exercise capacity in patients with a broad spectrum of cancer types, who were already receiving cancer treatment or about to commence such therapy. Exercise capacity was assessed in 253 consecutive patients mostly suffering from advanced cancer using the 6-min walk test (6-MWT). All patients underwent echocardiography, physical examination, resting electrocardiogram, hand grip strength (HGS) measurement, and laboratory assessments. Patients were divided into two groups according to the median distance in the 6-MWT (459 m). Patients with lower exercise capacity were older, had significantly lower HGS and haemoglobin and higher values of high sensitive (hs) Troponin T and NT-proBNP (all p < 0.05). Whilst the co-morbidity burden was significantly higher in this group, no differences were detected for sex, body mass index, tumor type, or cachexia (all p > 0.2). Using multivariable logistic regression, we found that the presence of anaemia (odds ratio (OR) 6.172, 95% confidence interval (CI) 1.401-27.201, p = 0.016) as well as an increase in hs Troponin T (OR 3.077, 95% CI 1.202-5.301, p = 0.019) remained independent predictors of impaired exercise capacity. Increasing HGS was associated with a reduced risk of a lower exercise capacity (OR 0.896, 95% CI 0.813-0.987, p = 0.026). Screening patients for elevated hs troponin levels as well as reduced HGS may help to identify patients at risk of lower exercise capacity during cancer treatment.

Cardiorespiratory fitness and health-related quality of life in survivors of childhood central nervous system tumours

PURPOSE

We assessed cardiorespiratory fitness and health-related quality of life (HRQoL) in survivors of childhood central nervous system (CNS) tumours.

METHODS

Participants were recruited from the National Children's Cancer Service in Children's Health Ireland at Crumlin. Inclusion criteria included diagnosis of a primary CNS tumour, aged between 6 and 17 years, between 3 months and 5 years post completion of oncology treatment, independently mobile, and deemed clinically appropriate to participate by treating oncologist. Cardiorespiratory fitness was assessed using the six-minute walk test. HRQoL was assessed with the PedsQL Generic Core Scales, Version 4.0.

RESULTS

Thirty-four participants (n = 16 male) were recruited, with a mean age of 12.21 ± 3.31 years and a mean time since completion of oncology treatment of 2.19 ± 1.29 years. Mean six-minute walk distance (6MWD) achieved was 489.56 ± 61.48 m, equating to the 8^th percentile overall. 6MWD was significantly reduced when compared to predicted population norms (p < 0.001). PedsQL parent proxy-report and child-report scores were significantly lower when compared to healthy paediatric norms (p < 0.001 - p = 0.011). A significant positive correlation was found between 6MWD and both parent proxy-report (r = 0.55, p < 0.001) and child-report (r = 0.48, p = 0.005) PedsQL total scores.

CONCLUSION

Survivors of childhood CNS tumours present with impaired cardiorespiratory fitness and HRQoL. Higher levels of cardiorespiratory fitness are associated with higher levels of HRQoL.

IMPLICATIONS FOR CANCER SURVIVORS

Routine screening of cardiorespiratory fitness and HRQoL in survivors of childhood CNS tumours may be beneficial. Healthcare providers should encourage and provide education on the potential benefits of physical activity to improve overall quality of life.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Cardiopulmonary Exercise Testing Characterizes Silent Cardiovascular Abnormalities in Asymptomatic Pediatric Cancer Survivors

Late-onset cardiovascular complications are serious concerns for pediatric cancer survivors (PCS) including those who are asymptomatic. We investigated whether cardiopulmonary exercise testing (CPET) can delineate the underlying pathophysiology of preclinical cardiovascular abnormalities in PCS. We examined CPET data via cycle ergometer in asymptomatic PCS with normal echocardiogram and age-matched controls. Peak and submaximal parameters were analyzed. Fifty-three PCS and 60 controls were studied. Peak oxygen consumption (VO₂), peak work rate (WR), and ventilatory anaerobic threshold (VAT) were significantly lower in PCS than controls (1.86 ± 0.53 vs. 2.23 ± 0.61 L/min, 125 ± 45 vs. 154 ± 46 W, and 1.20 ± 0.35 vs. 1.42 ± 0.43 L/min, respectively; all p < 0.01), whereas peak heart rate (HR) and ventilatory efficiency (a slope of minute ventilation over CO₂ production or ∆VE/∆VCO₂) were comparable. Peak respiratory exchange ratio (RER) was significantly higher in PCS (p = 0.0006). Stroke volume (SV) reserve was decreased in PCS, indicated by simultaneous higher dependency on HR (higher ∆HR/∆WR) and lower peak oxygen pulse (OP). Twelve PCS with high peak RER (≥ 1.3) revealed lower pVO₂ and VAT than the rest of PCS despite higher ventilatory efficiency (lower ∆VE/∆VCO₂), suggesting fundamental deficiency in oxygen utilization in some PCS. Poor exercise performance in PCS may be mainly attributed to limited stroke volume reserve, but the underlying pathophysiology is multifactorial. Combined assessment of peak and submaximal CPET parameters provided critical information in delineating underlying exercise physiology of PCS.

Diagnosis and Management of Cancer Treatment-Related Cardiac Dysfunction and Heart Failure in Children

It is disheartening for parents to discover that their children have long-term cardiac dysfunction after being cured of life-threatening childhood cancers. As the number of childhood cancer survivors increases, early and late oncology-therapy-related cardiovascular complications continues to rise. It is essential to understand that cardiotoxicity in childhood cancer survivors is persistent and progressive. A child's cancer experience extends throughout his lifetime, and ongoing care for long-term survivors is recognized as an essential part of the cancer care continuum. Initially, there was a lack of recognition of late cardiotoxicities related to cancer therapy. About 38 years ago, in 1984, pioneers like Dr. Lipshultz and others published anecdotal case reports of late cardiotoxicities in children and adolescents exposed to chemotherapy, including some who ended up with heart transplantation. At that time, cardiac tests for cancer survivors were denied by insurance companies because they did not meet appropriate use criteria. Since then, cardio-oncology has been an emerging field of cardiology that focuses on the early detection of cancer therapy-related cardiac dysfunction occurring during and after oncological treatment. The passionate pursuit of many healthcare professionals to make life better for childhood cancer survivors led to more than 10,000 peer-reviewed publications in the last 40 years. We synthesized the existing evidence-based practice and described our experiences in this review to share our current method of surveillance and management of cardiac dysfunction related to cancer therapy. This review aims to discuss the pathological basis of cancer therapy-related cardiac dysfunction and heart failure, how to stratify patients prone to cardiotoxicity by identifying modifiable risk factors, early detection of cardiac dysfunction, and prevention and management of heart failure during and after cancer therapy in children. We emphasize serial longitudinal follow-ups of childhood cancer survivors and targeted intervention for high-risk patients. We describe our experience with the new paradigm of cardio-oncology care, and collaboration between cardiologist and oncologist is needed to maximize cancer survival while minimizing late cardiotoxicity.

Exploring relationships between inspiratory muscle strength and functional capacity in childhood cancer survivors: a pilot study

Childhood cancer survivors (CCS) experience short- and long-term side effects from cancer treatment that often impair functional capacity. Inspiratory muscle weakness is a potential mechanism for reduced functional capacity. The objective of this pilot study was to examine the relationship between inspiratory muscle strength and functional capacity in 10 CCS. Inspiratory muscle strength was measured by maximal inspiratory pressure (MIP) while functional capacity was measured by the two-minute walk test (2MWT), the physiological cost index and hemodynamic response to exercise according to changes in heart rate, blood pressure and rate-pressure product (RPP). Overall, MIP and 2MWT distance were below predicted values. Hemodynamic responses to the 2MWT were consistent with little variation, except for elevated diastolic blood pressure (DBP) response. MIP had significant relationships with resting DBP (Spearman's rank correlation coefficient [r_s] = -0.70; p = 0.03) and DBP response (r_s = 0.72; p = 0.02). Time since completion of cancer treatment had a significant positive relationship with RPP response (r_s = 0.67; p = 0.03). Inspiratory muscle weakness in childhood cancer could be an indicator of skeletal muscle dysfunction and should be considered when symptoms of dyspnea or poor functional capacity arise. Inspiratory muscle strength was found to be related to changes in blood pressure in CCS. Future studies should further investigate these relationships and the impact of inspiratory muscle training on hemodynamics and functional capacity in CCS.

Cardiotoxicidad por antraciclinas en supervivientes de cáncer durante la infancia

Introducción: a nivel mundial, cada año cerca de 300.000 niños entre 0 y 19 años son diagnosticados con cáncer. El porcentaje de supervivientes va en aumento, llegando a 80 % en países desarrollados y 60 % en América Latina. Sin embargo, la expectativa y la calidad de vida de estas personas pueden verse comprometidas ante el desarrollo de cardiotoxicidad, un efecto adverso asociado al uso de algunos agentes antineoplásicos, como los antracíclicos.Objetivo: resaltar los aspectos clínicos relevantes para la prevención, detección oportuna, tratamiento y seguimiento de la cardiotoxicidad secundaria a la administración de antraciclinas durante la infancia.Síntesis de contenido: reflexión teórica que presenta consideraciones clínicas relevantes para guiar las acciones de enfermería y del equipo multidisciplinario en la atención y el cuidado de la salud cardiovascular de los supervivientes de cáncer a cualquier edad. Es importante destacar que en población pediátrica la única estrategia efectiva de prevención primaria para cardiotoxicidad por antraciclinas es la administración de dexrazoxano, mientras que la prevención secundaria debe incluir detección oportuna, control y  seguimiento de las alteraciones de la función cardíaca y de los factores de riesgo cardiovascular. Por su parte, la prevención terciaria se centra en el control de la enfermedad y el manejo farmacológico. Conclusiones: no existe un  tratamiento estándar para la cardiotoxicidad inducida por quimioterapia o radioterapia, siendo el objetivo principal de este tipo de tratamientos prevenir o retrasar la remodelación del ventrículo izquierdo. Todos los supervivientes requieren seguimiento vitalicio y búsqueda activa de signos de cardiotoxicidad, siendo fundamental la acción conjunta de diferentes profesionales y la consolidación de los servicios de cardio-oncología.

Assessment of late cardiotoxic effects in patients treated for cancer in childhood

Graphical AbstractThe aim was to assess the late cardiotoxic effects in young adults treated for various cancer types in childhood using echocardiography and 24-h ECG Holter monitoring.

Cardiovascular Function and Exercise Capacity in Childhood Cancer Survivors

Introduction: Childhood cancer survivors (CCS) might be at high risk of additional chronic diseases due to cardiotoxic side effects. The aim of this study was to analyze long-term side effects of cancer therapy on vascular structure/function, cardiac biomarkers and on physical activity. Methods: In total, 68 asymptomatic patients aged 16–30 years with childhood cancer (diagnosed 10.6 ± 3.9 years ago) were examined from 2015–2020. (Central) blood pressure and pulse wave velocity were registered via the oscillometric method, while carotid intima-media thickness (cIMT) was measured non-invasively by ultrasound. cIMT values of patients were compared to healthy controls (n = 68; aged 22.3 ± 3.5 years). Patients’ exercise capacity was recorded. The plasma N-terminal pro-brain natriuretic protein (NTproBNP) and troponin levels were measured as cardiac biomarkers. CCS were categorized in groups with low, moderate and high anthracyclines. Results: No differences were found in cIMT between patients and controls as well as between patients with various anthracycline dosage. Patients with high dose anthracyclines showed a significant lower performance versus patients with moderate dose anthracyclines (84.4% of predicted VO₂peak; p = 0.017). A total of 11.6% of CCS had abnormal NTproBNP values which correlated with received anthracycline dosage (p = 0.024; r = 0.343). Conclusion: NTproBNP levels and exercise capacity might be early markers for cardiovascular dysfunction in CCS and should be included in a follow-up protocol, while cIMT and troponin seem not to be adequate parameters.

Do Cancer and Cancer Treatments Accelerate Aging?

PURPOSE OF REVIEW

This review focuses on describing the mechanisms and clinical manifestations that underlie accelerated aging associated with cancer and its treatment.

RECENT FINDINGS

The direct and indirect effects of cancer and its treatment are associated with late occurrence of comorbidities that happen earlier or more frequently in cancer survivors compared to cancer-free individuals, otherwise known as accelerated aging. Use of senolytics and dietary and exercise interventions including prehabilitation, caloric restriction, and rehabilitation are currently under investigation to reverse or decelerate the aging process and will be covered in this review. Further research on how to decelerate or reverse aging changes associated with cancer and its treatment will be of paramount importance as the number of cancer survivors continues to grow.

Cardiotoxicity in pediatric lymphoma survivors

INTRODUCTION

Over the past five decades, the diagnosis and management of children with various malignancies have improved tremendously. As a result, an increasing number of children are long-term cancer survivors. With improved survival, however, has come an increased risk of treatment-related cardiovascular complications that can appear decades later.

AREAS COVERED

This review discusses the pathophysiology, epidemiology and effects of treatment-related cardiovascular complications from anthracyclines and radiotherapy in pediatric lymphoma survivors. There is a paucity of evidence-based recommendations for screening for and treatment of cancer therapy-induced cardiovascular complications. We discuss current preventive measures and strategies for their treatment.

EXPERT OPINION

Significant cardiac adverse effects occur due to radiation and chemotherapy received by patients treated for lymphoma. Higher lifetime cumulative doses, female sex, longer follow-up, younger age, and preexisting cardiovascular disease are associated with a higher incidence of cardiotoxicity. With deeper understanding of the mechanisms of these adverse cardiac effects and identification of driver mutations causing these effects, personalized cancer therapy to limit cardiotoxic effects while ensuring an adequate anti-neoplastic effect would be ideal. In the meantime, expanding the use of cardioprotective agents with the best evidence such as dexrazoxane should be encouraged and further studied.

Physical activity and fitness in childhood cancer survivors: a scoping review

BACKGROUND

Estimates indicate that nearly eight percent of the over 500,000 survivors of childhood cancer living in the United States are frail in their fourth and fifth decades of life, a phenotype typically seen in geriatric populations. Participation in regular physical activity to improve physical fitness in healthy and diseased populations reduces risk for frail health by increasing physiologic reserve. However, physical activity may not have the same effects on fitness in childhood cancer survivors as it does among their peers with no cancer history.

AIMS

This scoping review seeks to describe associations between physical activity, physical fitness, chronic disease, and mortality in childhood cancer survivors.

METHODS

Relevant literature was identified through a comprehensive search in the PubMed, Web of Science, CINAHL, and Cochrane databases. A narrative synthesis was performed on observational studies that had physical activity or physical fitness clearly defined and compared with chronic disease outcomes.

RESULTS

A total of 595 studies were screened, and results from 11 studies are presented. Childhood cancer survivors who participate in regular physical activity have improved markers of cardiovascular health, decreased risk of overt cardiovascular disease, and decreased risk of all-cause mortality compared to survivors who are not physically active. Childhood cancer survivors who are physically fit have increased neurocognition, and decreased risk of all-cause mortality compared to survivor's who are not fit. The differential effects of physical activity on fitness and health among childhood cancer survivors when compared to peers is potentially related to treatment exposures that damage cardiovascular tissue and impact regenerative potential.

CONCLUSION

Research is needed to determine the optimal timing, frequency, intensity, and duration of physical activity necessary to optimize fitness in childhood cancer survivors.

Cardiovascular risk management in cancer survivors: Are we doing it right?

Although under-recognized, cancer survivors continue to be at an increased risk of death from cardiovascular complications post-remission or cure. This increased burden of cardiovascular disease results from the interplay of various factors. Adequate cardiovascular risk assessment and timely intervention through a multi-disciplinary approach in these patients plays a pivotal role in the prevention of cardiovascular morbidity and mortality. We discuss the shortcomings of using current risk prediction scores in cancer survivors and provide some insights into cardiovascular risk management relevant for primary care physicians, oncologists, and cardiologists alike.

Exploring pulmonary function and physical function in childhood cancer: A systematic review

BACKGROUND

Children with cancer experience pulmonary and physical function side effects from the cancer itself and the medical interventions. This systematic review examines the known relationship between pulmonary function and physical function in childhood cancer and identifies gaps in the literature.

METHODS

A search of Ovid Medline, CINAHL (EbscoHost) and Embase to identify literature from 2009 to March 2020.

RESULTS

Fifty-seven studies met inclusion criteria. Thirty-seven studies reported impaired pulmonary function. Incidence of pulmonary dysfunction ranged from 45.5 % to 84.1 %. Eighteen studies reported impaired physical function. Three studies investigated the relationship between pulmonary function and physical function. No studies explored inspiratory muscle strength.

CONCLUSION

Pulmonary function and physical function are related and frequently impaired in children during and after cancer treatment. A literature gap was found in diaphragm function and its relationship with physical function. Future studies should focus on interventions that target the pulmonary mechanisms impacting physical function.

Within 5-year off-chemotherapy: How the cardio-respiratory response to exercise is related to energy expenditure, fatigue, and adiposity in children with acute lymphoblastic leukaemia?

OBJECTIVE

To explore the cardio-respiratory response to exercise and examine the relationships among specific measures of cardio-respiratory function, energy expenditure (EE), fatigue and adiposity in children survivors of acute lymphoblastic leukaemia (ALL).

METHODS

Seventy survivors of ALL (13.31 ± 2.60 years) and 34 controls from the siblings (12.71 ± 2.36 years) participated and were assessed for submaximal and maximal exercise capacity, body composition, EE and fatigue.

RESULTS

ALL survivors had significantly lower submaximal (VO₂ ; p = 0.002) and maximal (VO_2peak ; p ˂ 0.001) cardio-respiratory capacity than their controls. At the submaximal exercise test, EE was significantly lower in ALL survivors (p < 0.001), but the heart rate (HR) was significantly higher (p = 0.005). The VO₂ and HR were significantly correlated [r (95%CI) = 0.689 (0.542 to 0.795), p < 0.001]. The VO_2peak negatively associated with adiposity [r (95%CI) = -0.368 (-0.554 to -0.145), p = 0.002]. Fatigue significantly correlated with the VO_2peak [r (95%CI) = 0.581 (0.401 to 0.718), p < 0.001] and adiposity [r (95%CI) = -0.303 (-0.502 to 0.073), p = 0.012].

CONCLUSION

Children survivors of ALL experience low cardio-respiratory fitness within 5-year off-chemotherapy. Associations exist between measures of cardio-respiratory fitness, EE, fatigue and adiposity. However, it has not yet been proven whether these are cause or effect.

Young Adult Cancer Survivorship: Recommendations for Patient Follow-up, Exercise Therapy, and Research

Survivors of adolescent and young adult cancers (AYAs) often live 50 to 60 years beyond their diagnosis. This rapidly growing cohort is at increased risk for cancer- and treatment-related 'late effects' that persist for decades into survivorship. Recognition of similar issues in pediatric cancer survivors has prompted the development of evidence-based guidelines for late effects screening and care. However, corresponding evidence-based guidelines for AYAs have not been developed. We hosted an AYA survivorship symposium for a large group of multidisciplinary AYA stakeholders (approximately 200 were in attendance) at Princess Margaret Cancer Centre (Toronto, Ontario, Canada) to begin addressing this disparity. The following overview briefly summarizes and discusses the symposium's stakeholder-identified high-priority targets for late effects screening and care and highlights knowledge gaps to direct future research in the field of AYA survivorship. This overview, although not exhaustive, is intended to stimulate clinicians to consider these high-priority screening and care targets when seeing survivors in clinical settings and, ultimately, to support the development of evidence-based late effects screening and care guidelines for AYAs.

Exercise cardiovascular magnetic resonance reveals reduced cardiac reserve in pediatric cancer survivors with impaired cardiopulmonary fitness

BACKGROUND

Pediatric cancer survivors are at increased risk of cardiac dysfunction and heart failure. Reduced peak oxygen consumption (peak VO2) is associated with impaired cardiac reserve (defined as the increase in cardiac function from rest to peak exercise) and heart failure risk, but it is unclear whether this relationship exists in pediatric cancer survivors. This study sought to investigate the presence of reduced peak VO2 in pediatric cancer survivors with increased risk of heart failure, and to assess its relationship with resting cardiac function and cardiac haemodynamics and systolic function during exercise.

METHODS

Twenty pediatric cancer survivors (8-24 years; 10 male) treated with anthracycline chemotherapy ± radiation underwent cardiopulmonary exercise testing to quantify peak VO2, with a value < 85% of predicted defined as impaired peak VO2. Resting cardiac function was assessed using 2- and 3-dimensional echocardiography, with cardiac reserve quantified from resting and peak exercise heart rate, stroke volume index (SVI) and cardiac index (CI) using exercise cardiovascular magnetic resonance (CMR).

RESULTS

Twelve of 20 survivors (60%) had reduced peak VO2 (70 ± 16% vs. 97 ± 14% of age and gender predicted). There were no differences in echocardiographic or CMR measurements of resting cardiac function between survivors with normal or impaired peak VO2. However, those with reduced peak VO2 had diminished cardiac reserve, with a lesser increase in CI and SVI during exercise (Interaction P < 0.01 for both), whilst the heart rate response was similar (P = 0.71).

CONCLUSIONS

Whilst exercise intolerance is common among pediatric cancer survivors, it is poorly explained by resting measures of cardiac function. In contrast, impaired exercise capacity is associated with impaired haemodynamics and systolic functional reserve measured during exercise. Consequently, measures of cardiopulmonary fitness and cardiac reserve may aid in early identification of survivors with heightened risk of long-term heart failure.

Exercise testing and cardiac rehabilitation in patients treated for cancer

Cardiovascular disease (CVD) is a major competing cause of morbidity and mortality in patients with cancer. Cancer treatment can have detrimental short- and long-term cardiovascular effects. Moreover, cancer patients may have a significant loss in cardiorespiratory fitness, a key CVD risk factor, during and after cancer treatment. Exercise training has emerged as a potential intervention to improve fitness and reduce the risk of CVD in cancer. In this review, we discuss the role of cardiorespiratory fitness to predict cancer and CVD outcomes, as well as explore the impact of exercise training to improve fitness and other key outcomes in patients with cancer. The role of cardio-oncology rehabilitation will also be highlighted.

The 6-minute walk test is a good predictor of cardiorespiratory fitness in childhood cancer survivors when access to comprehensive testing is limited

Cardiovascular disease is up to 10 times more likely among childhood cancer survivors compared to siblings. Low cardiorespiratory fitness is a modifiable risk-factor for cardiovascular diseases. Yet, cardiorespiratory fitness is not routinely screened in pediatric oncology, and healthy VO2max cut-points are unavailable. We aimed to predict cardiorespiratory fitness by developing a simple algorithm and establish cut-points identifying survivors' cardiovascular fitness health-risk zones. We recruited 262 childhood cancer survivors (8-18 years old, ≥1-year posttreatment). Participants completed gold-standard cardiorespiratory fitness assessment (Cardiopulmonary Exercise Test [CPET; VO2max ]) and 6-minute walk test (6MWT). Associations with VO2max were included in a linear regression algorithm to predict VO2max , which was then cross-validated. We used Bland-Altman's limits of agreement and Receiver Operating Characteristic curves using FITNESSGRAM's "Healthy Fitness Zones" to identify cut-points for adequate cardiorespiratory fitness. A total of 199 participants (aged 13.7 ± 2.7 years, 8.5 ± 3.5 years posttreatment) were included. We found a strong positive correlation between VO2max and 6MWT distance (r = 0.61, r2 = 0.37, p < 0.001). Our regression algorithm included 6MWT distance, waist-to-height ratio, age and sex to predict VO2max (r = 0.79, r2 = 0.62, p < 0.001). Forty percentages of predicted VO2max values were within ±3 ml/kg/min of measured VO2max . The cut-point for FITNESSGRAM's "health-risk" fitness zone was 39.8 ml/kg/min (males: AUC = 0.88), and 33.5 ml/kg/min (females: AUC = 0.82). We present an algorithm to reasonably predict cardiorespiratory fitness for childhood cancer survivors, using inexpensive measures. This algorithm has useful clinical application, particularly when CPET is unavailable. Our algorithm has the potential to assist clinicians to identify survivors below the cut-points with increased cardiovascular disease-risk, to monitor and refer for tailored interventions with exercise specialists.

Childhood cancer survivors: The integral role of the cardiologist and cardiovascular imaging

IMPORTANCE

With 80% of childhood cancer survivors (CCS) alive 30 years after diagnosis, preventable causes of death, such as cardiovascular disease resulting from initial cancer therapy, becomes an important metric. This leads to a more pronounced role for cardiologists in the care of CCS.

OBSERVATIONS

While routine cardiovascular screening has been traditionally performed by the hematologist/oncologist or primary care provider, our understanding of cardiovascular disease in CCS has advanced. The measurement of left ventricular ejection fraction (LVEF) can now be complemented with additional assessments of strain, LV mass, right ventricular function, diastolic function, valve function, the pericardium, coronary perfusion, and biomarkers. Risk factor modification, prophylaxis, and timing of treatment are also critical.

CONCLUSIONS AND RELEVANCE

Early cardiovascular screening and treatment in asymptomatic CCS can be nuanced and complex. As a result, there is a renewed opportunity for the cardiologist to play an integral role in the care of CCS.

KEY POINTS

Question/Purpose: Review cardiovascular disease and the role of the cardiologist in the care of asymptomatic childhood cancer survivors (CCS).

FINDINGS

Cardiovascular care in CCS benefits from a multi-faceted approach that does not overly rely on LVEF. Meaning: Adequate screening and treatment of cardiovascular disease in asymptomatic CCS may often be optimized by the involvement of a cardiologist.

Cardiac autonomic dysfunction in survivors of childhood acute lymphoblastic leukemia: The St. Jude Lifetime Cohort Study

BACKGROUND

Cardiac autonomic dysfunction (CAD) is possible following treatment for childhood cancer. The aims of our analyses were to compare the prevalence of CAD between adult survivors of childhood acute lymphoblastic leukemia and controls, compare exercise response among survivors with and without CAD, and identify treatment-related risk factors for CAD.

PROCEDURE

Participants were treated for childhood acute lymphoblastic leukemia at St. Jude Children's Research Hospital between 1980 and 2003 (N = 338). A comparison group matched for race/ethnicity, age, and sex was also recruited (N = 325). Resting heart rate (HR) was assessed via electrocardiogram, and heart rate recovery (HRR) and exercise capacity were evaluated with submaximal cardiopulmonary exercise testing.

RESULTS

CAD was present in 33.7% of survivors and 27.6% of controls (P = 0.09). Although mean resting HR did not differ between survivors and controls (74 ± 12 vs 72 ± 12 beats per minute (bpm), P = 0.07), survivors had lower mean HRR than controls (22 ± 9 vs 25 ± 10 bpm; P < 0.001). Survivors with CAD had lower peak exercise tolerance (25.7 ± 6.5 vs 21.2 ± 4.9 mL/kg/min, P < 0.001) than those without. Survivors treated with cyclophosphamide in combination with vincristine ≥38 mg/m² and/or glucocorticoids ≥10 000 mg/m² were 1.56 (95% CI 1.09-2.24) times more likely to have CAD than those without this treatment. Obese survivors were 1.78 (95% CI: 1.31-2.40) times more likely to have CAD than nonobese survivors (P < 0.001).

CONCLUSION

CAD was present in over one third of survivors and was associated with lower exercise capacity. Obese survivors and those exposed to cyclophosphamide with high doses of vincristine and/or corticosteroids were at greatest risk.

Exercise Training for Cancer Survivors

OPINION STATEMENT

Cardiovascular diseases are a common cause of morbidity and mortality in cancer survivors. Furthermore, some cancer therapies are now being increasingly recognized to have negative cardiovascular effects, or cardiotoxicity. Exercise therapy has been found to improve cardiorespiratory fitness in patients with cancer as well as attenuate the cardiotoxic effects of cancer therapy. It is the centerpiece for cardiac and pulmonary rehabilitation programs. It is also an important component in cardio-oncology rehabilitation. Exercise is generally safe, and its benefit is observed when started as soon as the diagnosis of cancer and throughout cancer survivorship.

Cardio-Oncology Rehabilitation to Manage Cardiovascular Outcomes in Cancer Patients and Survivors: A Scientific Statement From the American Heart Association

Cardiovascular disease is a competing cause of death in patients with cancer with early-stage disease. This elevated cardiovascular disease risk is thought to derive from both the direct effects of cancer therapies and the accumulation of risk factors such as hypertension, weight gain, cigarette smoking, and loss of cardiorespiratory fitness. Effective and viable strategies are needed to mitigate cardiovascular disease risk in this population; a multimodal model such as cardiac rehabilitation may be a potential solution. This statement from the American Heart Association provides an overview of the existing knowledge and rationale for the use of cardiac rehabilitation to provide structured exercise and ancillary services to cancer patients and survivors. This document introduces the concept of cardio-oncology rehabilitation, which includes identification of patients with cancer at high risk for cardiac dysfunction and a description of the cardiac rehabilitation infrastructure needed to address the unique exposures and complications related to cancer care. In this statement, we also discuss the need for future research to fully implement a multimodal model of cardiac rehabilitation for patients with cancer and to determine whether reimbursement of these services is clinically warranted.

Subclinical Cardiac Dysfunction in Childhood Cancer Survivors on 10-Years Follow-Up Correlates With Cumulative Anthracycline Dose and Is Best Detected by Cardiopulmonary Exercise Testing, Circulating Serum Biomarker, Speckle Tracking Echocardiography, and Tissue Doppler Imaging

Background: Survivors of childhood cancer are at risk for anthracycline- and/or radiotherapy-induced cardiotoxicity. Aims: The aim of this study was to assess clinical, laboratory, and imaging parameters of subclinical cardiovascular disease in childhood cancer survivors. Methods: Patients underwent cardiopulmonary exercise test (CPET), laboratory testing, transthoracic echocardiography (TTE) with tissue doppler imaging (TDI) and speckle tracking. A subset of patients also underwent cardiovascular magnetic resonance imaging (CMR). Findings were correlated to cumulative anthracycline and exposure to mediastinal irradiation during cancer treatment. In a subgroup analysis, TTE and CMR findings were compared to data from 40 gender- and age-matched patients with childhood onset hypertrophic cardiomyopathy (HCM). Results: Cardiac evaluation was performed in 79 patients (43 males) at 11.2 ± 4.5 years after cancer treatment. Oncologic diagnosis at a median age of 12.0 years was Hodgkin lymphoma in 20, sarcoma in 17, acute leukemia in 24, relapse leukemia in 10, and others in 8 patients. Cumulative anthracycline dose exceeded 300 mg/m² in 28 patients. Twenty six patients also received mediastinal irradiation. Decreased peak respiratory oxygen uptake in % predicted on CPET, increased levels of N-terminal pro-brain natriuretic peptide (NTproBNP), increased global longitudinal strain on TTE speckle tracking, and diastolic dysfunction on TDI were the most prominent findings on detailed cardiology follow-up. In contrast to HCM patients, childhood cancer survivors did not show left ventricular hypertrophy (LVPWd z-score median 0.9 vs. 2.8, p < 0.001), hyperdynamic systolic function on TTE (Ejection fraction 62 ± 7 vs. 72 ± 12%, p = 0.001), or fibrotic myocardial changes on CMR (Late gadolinium positive 0/13 vs. 13/36, p = 0.001; extracellular volume fraction 22 ± 2 vs. 28 ± 3, p < 0.001) at time of follow-up. There was no correlation between chest radiation exposure and abnormal cardiac findings. Cumulative anthracycline dose was the only significant independent predictor on multivariate analysis for any cardiovascular abnormality on follow-up (p = 0.036). Conclusion: Increasing cumulative anthracycline dose during cancer treatment correlates with subclinical cardiac dysfunction in childhood cancer survivors best detected by elevated cardiac serum biomarkers, decreased exercise capacity on CPET, and abnormalities on echocardiographic speckle tracking and TDI.

Strategies to prevent anthracycline-induced cardiotoxicity in cancer survivors

Cancer diagnostics and therapies have improved steadily over the last few decades, markedly increasing life expectancy for patients at all ages. However, conventional and newer anti-neoplastic therapies can cause short- and long-term cardiotoxicity. The clinical implications of this cardiotoxicity become more important with the increasing use of cardiotoxic drugs. The implications are especially serious among patients predisposed to adverse cardiac effects, such as youth, the elderly, those with cardiovascular comorbidities, and those receiving additional chemotherapies or thoracic radiation. However, the optimal strategy for preventing and managing chemotherapy-induced cardiotoxicity remains unknown. The routine use of neurohormonal antagonists for cardioprotection is not currently justified, given the marginal benefits and associated adverse events, particularly with long-term use. The only United States Food and Drug Administration and European Medicines Agency approved treatment for preventing anthracycline-related cardiomyopathy is dexrazoxane. We advocate administering dexrazoxane during cancer treatment to limit the cardiotoxic effects of anthracycline chemotherapy.

Exercise Intolerance, Mortality, and Organ System Impairment in Adult Survivors of Childhood Cancer

PURPOSE

Exercise intolerance, associated with heart failure and death in general populations, is not well studied in survivors of childhood cancer. We examined prevalence of exercise intolerance in survivors exposed or not to cardiotoxic therapy, and associations among organ system function, exercise intolerance, and mortality.

METHODS

Participants consisted of 1,041 people who had survived cancer ≥ 10 years (and had or did not have exposure to anthracyclines and/or chest-directed radiation) and 285 control subjects. Exercise intolerance was defined as peak oxygen uptake < 85% predicted from maximal cardiopulmonary exercise testing; organ functions were ascertained with imaging or clinical testing. Multivariable regression of the data was performed to compare exercise capacity between survivors exposed or unexposed to cardiotoxic therapy and control subjects, and to evaluate associations between treatment and organ function, and organ function and exercise intolerance. Propensity score methods in time-to-event analyses evaluated associations between exercise intolerance and mortality.

RESULTS

Survivors (mean age ± standard deviation [SD], 35.6 ± 8.8 years) had lower mean (± SD) peak oxygen uptake (exposed: 25.74 ± 8.36 mL/kg/min; unexposed: 26.82 ± 8.36 mL/kg/min) than did control subjects (32.69 ± 7.75 mL/kg/min; P for all < .001). Exercise intolerance was present in 63.8% (95% CI, 62.0% to 65.8%) of exposed survivors, 55.7% (95% CI, 53.2% to 58.2%) of unexposed survivors, and 26.3% (95% CI, 24.0% to 28.3%) of control subjects, and was associated with mortality (hazard ratio, 3.9; 95% CI, 1.09 to 14.14). Global longitudinal strain (odds ratio [OR], 1.71; 95% CI, 1.11 to 2.63), chronotropic incompetence (OR, 3.58; 95% CI, 1.75 to 7.31); forced expiratory volume in 1 second < 80% (OR, 2.59; 95% CI, 1.65 to 4.09), and 1 SD decrease in quadriceps strength (OR, 1.49; 95% CI, 1.23 to 1.82) were associated with exercise intolerance. Ejection fraction < 53% was not associated with exercise intolerance.

CONCLUSION

Exercise intolerance is prevalent among childhood cancer survivors and associated with all-cause mortality. Treatment-related cardiac (detected by global longitudinal strain), autonomic, pulmonary, and muscular impairments increased risk. Survivors with impairments may require referral to trained specialists to learn to accommodate specific deficits when engaging in exercise.

Left and Right Ventricular Systolic and Diastolic Functional Reserves Are Impaired in Anthracycline-Treated Long-Term Survivors of Childhood Cancers

BACKGROUND

The aim of this study was to test the hypothesis that left ventricular (LV) and right ventricular (RV) functional reserves are altered in anthracycline-treated long-term survivors of childhood cancers.

METHODS

One hundred three survivors (55% men) aged 25.0 ± 5.8 years at 15.2 ± 5.8 years after chemotherapy and 61 healthy control subjects (52% men) were studied. Tissue Doppler-derived mitral and tricuspid systolic (s) and early diastolic (e) velocities and LV myocardial acceleration during isovolumic contraction (IVA) were determined at rest and during bicycle exercise. The slope of the LV force-frequency relationship was derived from changes in IVA with heart rate during exercise (ΔIVA/Δ[heart rate]). LV and RV functional reserves were further assessed by the systolic functional reserve index (Δs × [1 - 1/s at baseline]) and diastolic functional reserve index (Δe × [1 - 1/e at baseline]).

RESULTS

At baseline, mitral annular tissue Doppler indices were similar between survivors and control subjects (P > .05 for all), while tricuspid s and e velocities were significantly lower in survivors (P < .05 for both). The force-frequency relationship slope (P < .001), LV systolic functional reserve index (P < .001), and RV systolic functional reserve index (P = .001) were significantly lower in survivors than control subjects. For diastolic functional reserve, LV but not RV diastolic functional reserve index was significantly lower in survivors (P < .001). Multivariate analysis revealed survivor status (β = -0.39, P < .001) and baseline LV IVA (β = 0.15, P < .044) as significant determinants of the LV force-frequency relationship.

CONCLUSIONS

LV and RV functional reserves during exercise are impaired in anthracycline-treated long-term survivors of childhood cancer.

Cardiopulmonary Aerobic Fitness Assessment During Maximal and Submaximal Exercise Testing in Pediatric Oncology Patients After Chemotherapy

PURPOSE

The cardiopulmonary exercise test (CPET) is a valuable tool to assess cardiopulmonary exercise capacity in pediatric oncology patients after chemotherapy. In addition, few studies on the utility of submaximal testing have been performed, which could be important as some patients are unable to complete a maximal effort test secondary to deconditioning by both disease and treatment.

MATERIALS AND METHODS

We performed a retrospective chart review of pediatric cancer patients exposed to chemotherapy from 1992 to 2013 who underwent CPET with cycle ergometry (n=27). The study patients were compared with age-matched, sex-matched, and size-matched normal controls. The submaximal measure recorded was the oxygen consumption (VO2)@respiratory exchange ratio (RER) 1.0 during a maximal effort test.

RESULTS

The chemotherapy group demonstrated significantly lower exercise time (9.2±3.6 vs. 11.4±3.8; P=0.008), total work capacity (4914.4±3290.3 vs. 7664.4±4289.5; P=0.004), systolic blood pressure at peak exercise (162.9±23.2 vs. 177.3±23.8; P=0.01), indexed peak VO2 (33.9±6.9 vs. 40.0±6.3; P=0.001), and indexed peak oxygen pulse (6.1±1.3 vs. 7.0±1.5; P=0.004)). For the submaximal outcome measured, 11/27 of the chemotherapy patients had VO2@RER 1.0 values <-2 SD from the mean compared with 0/27 control patients.

CONCLUSIONS

Pediatric patients exposed to chemotherapy have impaired cardiopulmonary exercise capacity. The VO2@RER 1.0 in chemotherapy patients suggests that this may be a reliable submaximal measure in this population.

IMPLICATIONS FOR CANCER SURVIVORS

This study demonstrates that the CPET can be used in pediatric cancer survivors with prior exposure to chemotherapy to demonstrate impaired cardiopulmonary exercise tolerance, which is demonstrated on submaximal and maximal effort testing.

Cardiovascular disease in survivors of childhood cancer

PURPOSE OF REVIEW

We review the cardiotoxic chemotherapeutic agents, the clinical and subclinical presentations and progression of their cardiotoxicity, and the management of the subsequent cardiovascular disease in survivors of childhood cancer. We discuss various preventive measures, especially the cardioprotectant, dexrazoxane, whose use with anthracycline chemotherapy, including doxorubicin, is based on strong evidence. Most treatment recommendations for this unique population are based on expert opinion, not on empirical evidence.

RECENT FINDINGS

As patients with childhood cancers live longer, morbidity from the cardiac side effects of chemotherapy is increasing. Treatment-related cardiac damage is irreversible and often progressive. It is imperative that such damage be prevented with strategies such as limiting the cumulative anthracycline dose, the use of anthracycline structural analogues and the use of cardioprotective agents.

SUMMARY

A deeper understanding of the mechanisms of their cardiotoxicity reveals that there is no 'safe' dose of anthracyclines. However, certain risk factors, such as higher lifetime anthracycline cumulative doses, higher anthracycline dose rates, female sex, longer follow-up, younger age at anthracycline treatment and cardiac irradiation, are associated with more severe cardiotoxicity. We advocate the use of dexrazoxane to limit the cardiotoxic effects of anthracycline chemotherapy.

Hospitalization and mortality among pediatric cancer survivors: a population-based study

PURPOSE

We examined serious long-term outcomes among childhood cancer survivors using population-based data.

METHODS

We used 1982-2014 Washington State data to compare hospitalization and/or death (including cause-specific) during up to 27 years follow-up among all 5+ year childhood cancer survivors < 20 years at diagnosis (n = 3,152) and a sample of comparison children within birth cohorts, with assessment by cancer type and child/family characteristics.

RESULTS

During follow-up (9 years median), 12% of survivors had hospitalizations; 4% died. Greatest absolute risks/1,000 person-years were for hospitalization/deaths due to cancers (8.1), infection (6.2), injuries (6.0), and endocrine/metabolic disorders (5.8). Hazard ratios (HR) and 95% confidence intervals (CI) for hospitalization (2.7, 95% CI 2.4-3.0) and any-cause death (14.7, 95% CI 11.3-19.1) were increased, and for all cause-specific outcomes examined, most notably cancer- (35.1, 95% CI 23.7-51.9), hematological- (6.7, 95% CI 5.3-8.5), nervous system- (6.4, 95% CI 5.2-7.8), and circulatory- (5.2, 95% CI 4.1-6.5) related outcomes. Hospitalizations occurred more often among females and those receiving radiation, with modest differences by urban/rural birth residence and race/ethnicity. Cause-specific outcomes varied by cancer type.

CONCLUSIONS

This study suggests increased risks for the rarely-studied outcomes of long-term fracture and injury, and confirms increased risks of selected other conditions among survivors. Multi-state pooling of population-based data would increase the ability to evaluate outcomes for uncommon cancer types and by racial/ethnic groups under-represented in many studies.

Health-related fitness in very long-term survivors of childhood cancer: A cross-sectional study

BACKGROUND

Impairment of health-related physical fitness (HRPF) in survivors of acute lymphoblastic leukemia has been shown. However, evidence of impairment in survivors of other pediatric malignancies and possible risk factors is limited.

PARTICIPANTS AND METHODS

HRPF of 17 survivors of pediatric acute myeloid leukemia (AML), 26 survivors of neuroblastoma (NBL), 28 survivors of Wilms tumor (WT) (median age 28.8 [18.8-62.6] years) after a median follow-up time of 24.5 (6.5-43.6) years, and 74 healthy controls (median age 26.9 [17.9-61.7] years). Risk factors were investigated. Testing included submaximal cardiovascular endurance (6-Minute Walk Test (6 MWT), flexibility, and muscle strength.

RESULTS

Results are expressed as mean (standard error). Survivors scored significantly lower than controls on the 6 MWT (588 ± 6.1 m vs. controls 611 ± 6.0 m; P = 0.008), on side flexion of the trunk (20.1 ± 0.4 cm vs. controls 22.4 ±0.4 cm; P < 0.001), and on vertical jump (39.7 ± 0.8 cm vs. controls 43.8 ± 0.8 cm; P < 0.001). Survivors of AML had lower scores on the 6 MWT (563 ± 12.4 m) than survivors of NBL (585 ± 9.9 m) and survivors of WT (606 ± 9.6 m), P = 0.046. Being a survivor, higher body mass index (BMI) and no participation in sports were independently associated with lower scores on the 6 MWT.

CONCLUSION

Survivors of NBL, WT, and especially AML have impaired HRPF. Higher BMI and physical inactivity at adult age appeared prominent risk factors for impaired HRPF in these survivors.

Exercise capacity in young adults after hematopoietic cell transplantation in childhood

A symptom-limited incremental cycle ergometer test was performed in 17 young adult patients treated with hematopoietic cell transplantation and total body irradiation for hematologic malignancies during childhood. These 17 young adult patients were compared with 17 sex- and age-matched healthy control subjects. Assessments of pulmonary function, cardiac function, body composition, and levels of growth hormone were made. The median follow-up was 17.7 years. Patients achieved 63.2% of the predicted peak workload, whereas controls achieved 96.1% (P < .001). All patients, but only 1 control, failed to achieve a peak workload >80% (P < .001). Fat-free mass was significantly lower (43.5 vs 57.6 kg, P < .001) and fat mass percentage was significantly higher (31.8% vs 24.2%, P = .011) in the patients. The peak workload adjusted for fat-free mass was significantly lower in the patients (3.3 vs 4.3, P < .001). In the patients, peak workload correlated significantly with total lung capacity (r = .54, P = .025). In summary, long-term survivors have significantly decreased exercise capacity compared with healthy individuals. Together with their altered body composition, this may predispose them to cardiovascular disease.

Compulsory military service as a measure of later physical and cognitive performance in male survivors of childhood cancer

BACKGROUND

Compromised physical fitness and cognitive difficulties have been reported as late effects of cancer treatment during childhood. To assess this issue, the military rankings of cancer survivors in medical checkups at call-up, and conscripts' physical and cognitive performance during the first weeks of compulsory military education were compared to those of matched population controls without a history of cancer.

MATERIAL AND METHODS

A total of 1680 male patients born between 1960 and 1992 with a malignancy diagnosed before the age of 16 who were alive at the call-up age (18 years) were identified using the Finnish Cancer Registry, and five age, sex and place of residence matched controls for each patient using the Population Register Centre. Data on military service were gathered from Finnish Defense Forces. A conditional logistic regression analysis, the GEE-method with the cumulative logit link function, the chi-square test, the chi-square test for trend and a one-way analysis of variance were used in different analyses.

RESULTS

Cancer survivors were exempted from military service more often than the controls (p < .001). The fit-for-service frequency was highest for survivors of kidney tumors (68%) and lowest after irradiated brain tumors (19%). In service, the results of the 12-min running test were poorer than those of controls for leukemia/non-Hodgkin lymphoma (p = .03) and brain tumor (p = .01) survivors. Interestingly, the standing long-jump test was the only muscle test for which survivor groups performed worse than controls. Performance on cognitive tests only differed from controls in brain tumor survivors.

CONCLUSIONS

Exemption from service is still common under the current guidelines, but fit-for-service survivors do well in military education. These results can be used for reassuring survivors that completion of military service is possible for those fulfilling the national general guidelines for military fitness.

Prevention of cardiotoxicity among survivors of childhood cancer

LINKED ARTICLES

This article is part of a joint Themed section with the British Journal of Pharmacology on Cardiotoxicity. The rest of the Themed section will appear in a future issue of BJP and will be available at http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1476-5381 The number of survivors of childhood cancers has increased exponentially over the past few decades. However, these survivors are also at substantially increased long-term risk of morbidity and mortality, especially from treatment-related cardiotoxicity. Preventing these risks is now a priority when treating children and adolescents with cancer. Dexrazoxane reduces the risk of anthracycline-induced cardiotoxicity among adults and children with cancer without reducing its antineoplastic effects or event-free survival. Thus, it should be strongly considered as a part of therapy for children and adolescents treated with anthracyclines.

Getting the SCOOP-Survey of Cardiovascular Outcomes From Oncology Patients During Survivorship

BACKGROUND

Cardiovascular (CV) disease is the second most common cause of mortality and morbidity in cancer survivors (CS). Limited data exist on the knowledge and awareness of CS about CV effects of cancer therapies and its effect on lifestyle of survivors. It is important to identify gaps in CV care of CS.

MATERIALS AND METHODS

A brief voluntary, anonymous, web-based questionnaire was designed to assess the awareness of CS about the interaction between CV disease, CV symptoms and lifestyle changes from cancer treatment.

RESULTS

A total of 213 volunteers (181 women) with mean age of 56 years responded to the survey. Breast cancer was the most prevalent cancer diagnosis. In all, 15% reported CV disease before therapy with a higher incidence of CV disease in survivors more than 5 years from diagnosis (20% >5 years versus 10% <5 years of survivorship, P = 0.05). The reported use of beta blockers (9%) and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (9%) was rare despite the high incidence of CV disease. Only one-fourth of survivors were offered CV screening during treatment, whereas 36% of survivors had unanswered questions about CV symptoms from therapy. The CV symptoms adversely affected lifestyle in 27% of CS. One-fifth of survivors received exercise counseling even though half would have liked counseling.

CONCLUSIONS

The survey demonstrates that CS have self-reported CV symptoms and there may be unmet needs for CV preventive services. Further work is needed to develop collaborative patient counseling and management strategies between oncology and cardiology for improving CV health and symptoms of CS.

Late Cardiotoxicity: Issues for Childhood Cancer Survivors

OPINION STATEMENT

Cardiovascular-related morbidity is a substantial health burden in survivors of childhood cancers. This burden is gaining importance as this population increases through advancements in therapy. Anthracyclines are commonly used agents that are known to cause late cardiotoxicity. Cardiotoxicity is also increased by other risk factors, such as concurrent radio- or chemotherapy, younger age at diagnosis, female sex, comorbidities, lifestyle factors, and genetic factors, such as hemochromatosis gene mutations. Treatment of late cardiotoxicity depends on the type of cardiac abnormalities and consists of pharmacotherapy, mechanical support, or heart transplantation. Because cardiotoxicity is progressive and often irreversible, prevention, risk reduction, and early detection are of utmost importance. The cardioprotectant dexrazoxane decreases anthracycline cardiotoxicity. Screening for other risk factors at the time of diagnosis may identify risk that when present, if used to tailor therapy, may reduce the severity of cardiac damage. The effects of exercise and other lifestyle changes in reducing the cardiovascular diseases in cancer survivors are unclear. However, it may be beneficial to encourage survivors to engage in physical activity tailored to survivor medical status, but with close monitoring.

Motor Performance After Treatment for Pediatric Bone Tumors

BACKGROUND

Reduced motor performance can negatively affect physical activity and social partake after childhood cancer. Especially in bone tumor patients, who are at risk of physical limitations due to surgical interventions, motor performance has not yet been sufficiently investigated. Therefore, this study aimed at assessing motor performance in pediatric bone tumor patients.

PROCEDURE

Motor performance was measured within 2 years posttreatment using the MOON (test for MOtor performance in pediatric ONcology) test. This instrument enables quantitative data collection even in physically impaired patients for comparison with age-matched and sex-matched reference values.

RESULTS

Twenty-one patients (13 male) ages 15.2±2.1 years (median: 15 y, 10 to 19 y) and 9.4±7.4 months posttreatment (median: 6 mo, 2 to 24 mo) were tested. Motor performance was slightly reduced in muscular endurance of the legs; significantly reduced in speed, flexibility, eye-hand coordination, and muscular explosive strength (P<0.001), whereas patients' hand grip strength and static balance were superior to the reference values. Follow-up duration, body mass index, and tumor localization apparently affected motor performance.

CONCLUSIONS

These findings show serious reductions in motor performance within 2 years after bone tumor treatment and highlight the need for interventions to improve motor performance. The results should be used to advise and support patients to engage in suitable physical and sports activities.

Impaired exercise capacity and left ventricular function in long-term adult survivors of childhood acute lymphoblastic leukemia

BACKGROUND

Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for late cardiotoxic effects of cancer treatment, but conflicting evidence exists on the effects of anthracyclines on left ventricular (LV) diastolic function and exercise capacity.

PROCEDURE

We performed a cross-sectional study with comprehensive echocardiography in 138 adult survivors of childhood ALL, median 23.4 years after diagnosis. Pulsed tissue Doppler measurements of early diastolic mitral annular velocities (e') were used for the assessment of diastolic function, and compared to 138 matched controls. Of the survivors, 133 also performed ergospirometry measuring peak oxygen uptake (VO2 max). Associations between cancer treatment, LV function, and VO2 max were analyzed.

RESULTS

The survivor group had lower e' values than controls (e' septal 11.0 vs. 12.6 cm/s, P < 0.001), but the difference was confined to the subgroup of anthracycline treated survivors (median cumulative dose 120 mg/m(2) ). Anthracycline exposure was inversely correlated with e' (regression coefficient -1.581, P=0.009). Reduced VO2 max/kg occurred in 47% of the survivors, but more often in anthracycline treated survivors (56%) than anthracycline naïve survivors (17%, P<0.001). Anthracycline exposure was inversely correlated with VO2 max/kg (regression coefficient -3.084, P = 0.05 in multivariate analysis). Furthermore, associations were observed between measures of LV function and VO2 max/kg, and e' was the best predictor of VO2 max/kg (standardized coefficient 0.355, P < 0.001 in multivariate analysis).

CONCLUSIONS

Adult survivors of childhood ALL have increased risk for impaired LV diastolic function and impaired exercise capacity, both associated with previous anthracycline exposure. Furthermore, there is an association between LV diastolic function and exercise capacity.