Dexrazoxane in Children With Cancer: From Evidence to Practice

Cardiotoxicity in children with cancer treated with anthracyclines: A position statement on dexrazoxane

Cardiovascular disease is the leading cause of non-malignant morbidity and mortality in childhood cancer survivors (CCSs). Anthracyclines are included in many treatment regimens for paediatric cancer, but unfortunately, these compounds are cardiotoxic. One in 10 CCSs who has received an anthracycline will develop a symptomatic cardiac event over time. Given the crucial need to mitigate anthracycline-related cardiotoxicity (ARC), the authors critically examined published data to identify effective cardioprotective strategies. Based on their expert analysis of contemporary literature data, it was concluded that consideration should be given for routine use of dexrazoxane in children with cancer who are at risk of ARC.

The role of temporary mechanical circulatory support in de novo heart failure syndromes with cardiogenic shock: A contemporary review

Cardiogenic shock (CS) is a complex clinical syndrome with a high mortality rate. It can occur to due to multiple etiologies of cardiovascular disease and is phenotypically heterogeneous. Acute myocardial infarction-related CS (AMI-CS) has historically been the most prevalent cause, and thus, research and guidance have focused primarily on this. Recent data suggest that the burden of non-ischemic CS is increasing in the population of patents requiring intensive care admission. There is, however, a paucity of data and guidelines to inform the management of these patients who fall into two broad groups: those with existing heart failure and CS and those with no known history of heart failure who present with "de novo" CS. The use of temporary mechanical circulatory support (MCS) has expanded across all etiologies, despite its high cost, resource intensity, complication rates, and lack of high-quality outcome data. Herein, we discuss the currently available evidence on the role of MCS in the management of patients with de novo CS to include fulminant myocarditis, right ventricular (RV) failure, Takotsubo syndrome, post-partum cardiomyopathy, and CS due to valve lesions and other cardiomyopathies.

Dexrazoxane Treatments Limits Subclinical Cardiac Dysfunction in Childhood Acute Lymphoblastic Leukemia Survivors Exposed to Doxorubicin Treatments

INTRODUCTION

Doxorubicin leads to dose dependent cardiotoxicity in childhood acute lymphoblastic leukemia (ALL) survivors. We investigated survivors' heart health using echocardiography and evaluated doxorubicin and dexrazoxane treatments on cardiac function.

METHODS

A total of 196 childhood ALL survivors were stratified (standard risk [SR], high risk with and without dexrazoxane (HR+DEX and HR). We performed a complete transthoracic echocardiographic assessment with M-mode echocardiography, Doppler, and Tissue Doppler. We used 2-dimensional and 3-dimensional echocardiography to measure the left ventricular ejection fraction, whereas myocardial strain imaging was used to obtain global strain indices.

RESULTS

Although most cardiac and arterial dimension parameters were not different between groups, a difference was observed in posterior intima of the right carotid ( P =0.017). Diastolic functions analyses reported that LV shortening fraction and left and right ventricular lateral S' wave amplitudes were lower in HR than in SR and HR+DEX groups ( P =0.028, P =0.048, and P =0.005, respectively). The LV lateral E' in diastolic function was lower in the HR than in SR and HR+DEX groups ( P =0.036). The LV end-systolic wall stress was higher in HR than in SR and HR+DEX groups ( P =0.009). A decrease contractility was observed, while the effect was not group specific. Strain rate was not different between groups, as opposed to tissue Doppler measurements.

CONCLUSIONS

This study showed that dexrazoxane treatments could limit subclinical cardiac dysfunction in childhood ALL survivors, whereas survivors in HR group who did not receive dexrazoxane had potential subclinical cardiac damage observable in heart failure patients. Echocardiographic screening for survivors must be part of the follow-up routine in cardio-oncology.

Saponins and their derivatives: Potential candidates to alleviate anthracycline-induced cardiotoxicity and multidrug resistance

Anthracyclines (ANTs) continue to play an irreplaceable role in oncology treatment. However, the clinical application of ANTs has been limited. In the first place, ANTs can cause dose-dependent cardiotoxicity such as arrhythmia, cardiomyopathy, and congestive heart failure. In the second place, the development of multidrug resistance (MDR) leads to their chemotherapeutic failure. Oncology cardiologists are urgently searching for agents that can both protect the heart and reverse MDR without compromising the antitumor effects of ANTs. Based on in vivo and in vitro data, we found that natural compounds, including saponins, may be active agents for other both natural and chemical compounds in the inhibition of anthracycline-induced cardiotoxicity (AIC) and the reversal of MDR. In this review, we summarize the work of previous researchers, describe the mechanisms of AIC and MDR, and focus on revealing the pharmacological effects and potential molecular targets of saponins and their derivatives in the inhibition of AIC and the reversal of MDR, aiming to encourage future research and clinical trials.

Cardio-toxicity in childhood cancer survivors "Cure is not enough"

The number of pediatric cancer survivors is growing, and they are getting older. Therapy-induced cardiotoxicity therefore is debated as an ongoing problem. Recognition of the side effects in the use of anthracyclines and radiation as well as the patients' clinical condition and comorbidities leads back as far as the beginning of systematic cancer treatment in children in the 1980s. Since, numerous case reports, meta-analyses and retrospective surveys were published worldwide. However, randomized clinical trials with standardized protocols yet fail to be designed. This article gives an overview of the recent reports and emphasizes on the heterogeneity of the different approaches. A standardized work-up which may identify the patient at risk-including the patient's history and condition, individual genetic dispositions, dosage and method of drug application, consideration of co-medication, radiation therapy and dose, standardized imaging methods-is the main proposition of our report. The fusion of already established sources, e.g., data of different registries or study centers, might help to create preventive strategies for and a better understanding of patients with therapy induced cardiomyopathy.

Late-onset cardiomyopathy among survivors of childhood lymphoma treated with anthracyclines: a systematic review

Medical advances in pediatric oncology have led to increases in survival but the long-term adverse effects of treatment in childhood cancer survivors have not yet been examined in depth. In this systematic review, we aimed to study the prevalence and risk factors of late-onset cardiomyopathy (LOCM) among survivors of childhood lymphoma treated with anthracyclines. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines we searched Pubmed/Medline, abstracted data and rated studies on quality regarding late-onset (>1 year following treatment) cardiotoxicity of anthracyclines in survivors of childhood lymphoma. Across 22 identified studies, the prevalence of anthracycline-induced LOCM among survivors of childhood lymphoma ranges from 0 to 40%. Anthracycline dose, administration and dose of mediastinal radiation, patient's age and era of diagnosis and evaluation, follow-up duration as well as disease relapse have been reported as risk factors for LOCM, whereas administration of dexrazoxane seems to act protectively. There was significant between-study heterogeneity with regards to lymphoma subtypes, follow-up duration, definition of outcomes, and anthracycline-based treatment protocols. The rates of anthracycline-induced LOCM among survivors of childhood lymphoma are high and dependent on study design. Future studies should explore whether modifying risk factors and suggested supportive care could decrease its prevalence among childhood lymphoma survivors. Until then, lifelong follow-up of these patients aiming to determinate the earliest signs of cardiac dysfunction is the most important measure towards primordial prevention of LOCM.

Cardiovascular Disease in Survivors of Childhood Cancer: Insights Into Epidemiology, Pathophysiology, and Prevention

Cardiovascular disease (CVD), which includes cardiomyopathy/heart failure, coronary artery disease, stroke, pericardial disease, arrhythmias, and valvular and vascular dysfunction, is a major concern for long-term survivors of childhood cancer. There is clear evidence of increased risk of CVD largely attributable to treatment exposures at a young age, most notably anthracycline chemotherapy and chest-directed radiation therapy, and compounded by traditional cardiovascular risk factors accrued during decades after treatment exposure. Preclinical studies are limited; thus, it is a high priority to understand the pathophysiology of CVD as a result of anticancer treatments, taking into consideration the growing and developing heart. Recently developed personalized risk prediction models can provide decision support before initiation of anticancer therapy or facilitate implementation of screening strategies in at-risk survivors of cancer. Although consensus-based screening guidelines exist for the application of blood and imaging biomarkers of CVD, the most appropriate timing and frequency of these measures in survivors of childhood cancer are not yet fully elucidated. Longitudinal studies are needed to characterize the prognostic importance of subclinical markers of cardiovascular injury on long-term CVD risk. A number of prevention trials across the survivorship spectrum are under way, which include primary prevention (before or during cancer treatment), secondary prevention (after completion of treatment), and integrated approaches to manage modifiable cardiovascular risk factors. Ongoing multidisciplinary collaborations between the oncology, cardiology, primary care, and other subspecialty communities are essential to reduce therapeutic exposures and improve surveillance, prevention, and treatment of CVD in this high-risk population.

Dexrazoxane improves cardiac autonomic function in epirubicin-treated breast cancer patients with type 2 diabetes

OBJECTIVE

The study objective was to investigate the protective effects of dexrazoxane (DRZ) on the cardiac autonomic nervous system (ANS) activity in anthracycline-treated breast cancer patients with diabetes.

METHODS

A total of 110 early stage breast cancer patients with type 2 diabetes were divided randomly into 2 even groups: chemotherapy alone (Chemo) and chemotherapy + DRZ (Chemo + DRZ). All patients underwent adjuvant chemotherapy (80 mg/m epirubicin and 500 mg/m cyclophosphamide) for a total of 6 cycles with 21 days/cycle. The Chemo + DRZ group patients were treated intravenously with 800 mg/m DRZ 30 minutes prior to the administration of epirubicin, while the Chemo group patients were given saline. The cardiac ANS function was evaluated for each patient before and after 6 cycles of chemotherapy by resting heart rate (RHR) and heart rate variability (HRV), which was evaluated by both time and frequency domains.

RESULTS

Before and after chemotherapy, patients in both groups showed significant decreases in HRV indices and increases in RHR and the low-frequency/high-frequency ratio. There were no significant differences between Chemo and Chemo + DRZ groups in terms of RHR and HRV indices before chemotherapy; however, after chemotherapy, patients in the Chemo group had a higher average RHR and lower HRV indices compared with patients in the Chemo + DRZ group.

CONCLUSION

DRZ protects the cardiac ANS in epirubicin-treated early stage breast cancer patients with diabetes.

Cardio-oncology: Concepts and practice

Substantial progress in cancer therapy increasingly allows higher cure rates, and even advanced disease can be stabilized, allowing improved survival with quality of life for months to years, meaning comorbid diseases are a growing determinant of outcome. Cardiovascular events substantially contribute to long-term morbidity and mortality in people living with or surviving cancer. In recognition of this, the subspecialty of cardio-oncology has emerged, and aims to promote cardiovascular heath, whilst facilitating the most effective cancer therapy. This review describes the concept of cardio-oncology, and illustrates the role played by a specialist team in improving outcomes, using heart failure secondary to breast cancer treatment as an example. We aim to highlight pivotal original research and comprehensive summaries of the most relevant topics, providing an overview for cardiologists and oncologists about this increasingly important medical problem.