Late Mortality After Dexrazoxane Treatment: A Report From the Children's Oncology Group

Molecular Mechanisms and Therapeutic Targeting of Ferroptosis in Doxorubicin-Induced Cardiotoxicity

Ferroptosis, an iron-dependent form of regulated cell death, has received increasing attention for its pathophysiologic contribution to the onset and development of doxorubicin-induced cardiotoxicity. Moreover, modulation of ferroptosis with specific inhibitors may provide new therapeutic opportunities for doxorubicin-induced cardiotoxicity. Here, we will review the molecular mechanisms and therapeutic promise of targeting ferroptosis in doxorubicin-induced cardiotoxicity.

Association of European Paediatric and Congenital Cardiology practical recommendations for surveillance and prevention of cardiac disease in childhood cancer survivors: the importance of physical activity and lifestyle changes From the Association of European Paediatric and Congenital Cardiology Working Group Sports Cardiology, Physical Activity and Prevention, Working Group Adult Congenital Heart Disease, Working Group Imaging and Working Group Heart Failure

BACKGROUND

Childhood cancer survivors are at increased risk of developing cardiovascular diseases, presenting as the main causes of morbidity and mortality within this group. Besides the usual primary and secondary prevention in combination with screening during follow-up, the modifiable lifestyle factors of physical activity, nutrition, and body weight have not yet gained enough attention regarding potential cardiovascular risk reduction.

OBJECTIVE

These practical recommendations aim to provide summarised information and practical implications to paediatricians and health professionals treating childhood cancer survivors to reduce the risk of cardiovascular late effects.

METHODS

The content derives from either published guidelines or expert opinions from Association of European Paediatric and Congenital Cardiology working groups and is in accordance with current state-of-the-art.

RESULTS

All usual methods of prevention and screening regarding the risk, monitoring, and treatment of occurring cardiovascular diseases are summarised. Additionally, modifiable lifestyle factors are explained, and clear practical implications are named.

CONCLUSION

Modifiable lifestyle factors should definitely be considered as a cost-effective and complementary approach to already implemented follow-up care programs in cardio-oncology, which can be actively addressed by the survivors themselves. However, treating physicians are strongly encouraged to support survivors to develop and maintain a healthy lifestyle, including physical activity as one of the major influencing factors. This article summarises relevant background information and provides specific practical recommendations on how to advise survivors to increase their level of physical activity.

Rationale and design of the Children's Oncology Group study AAML1831 integrated cardiac substudies in pediatric acute myeloid leukemia therapy

Background

Pediatric acute myeloid leukemia (AML) therapy is associated with substantial short- and long-term treatment-related cardiotoxicity mainly due to high-dose anthracycline exposure. Early left ventricular systolic dysfunction (LVSD) compromises anthracycline delivery and is associated with inferior event-free and overall survival in de novo pediatric AML. Thus, effective cardioprotective strategies and cardiotoxicity risk predictors are critical to optimize cancer therapy delivery and enable early interventions to prevent progressive LVSD. While dexrazoxane-based cardioprotection reduces short-term cardiotoxicity without compromising cancer survival, liposomal anthracycline formulations have the potential to mitigate cardiotoxicity while improving antitumor efficacy. This overview summarizes the rationale and methodology of cardiac substudies within AAML1831, a randomized Children's Oncology Group Phase 3 study of CPX-351, a liposomal formulation of daunorubicin and cytarabine, in comparison with standard daunorubicin/cytarabine with dexrazoxane in the treatment of de novo pediatric AML.

Methods/design

Children (age <22 years) with newly diagnosed AML were enrolled and randomized to CPX-351-containing induction 1 and 2 (Arm A) or standard daunorubicin and dexrazoxane-containing induction (Arm B). Embedded cardiac correlative studies aim to compare the efficacy of this liposomal anthracycline formulation to dexrazoxane for primary prevention of cardiotoxicity by detailed core lab analysis of standardized echocardiograms and serial cardiac biomarkers throughout AML therapy and in follow-up. In addition, AAML1831 will assess the ability of early changes in sensitive echo indices (e.g., global longitudinal strain) and cardiac biomarkers (e.g., troponin and natriuretic peptides) to predict subsequent LVSD. Finally, AAML1831 establishes expert consensus-based strategies in cardiac monitoring and anthracycline dose modification to balance the potentially competing priorities of cardiotoxicity reduction with optimal leukemia therapy.

Discussion

This study will inform diagnostic, prognostic, preventative, and treatment strategies regarding cardiotoxicity during pediatric AML therapy. Together, these measures have the potential to improve leukemia-free and overall survival and long-term cardiovascular health in children with AML. Clinical trial registration: https://clinicaltrials.gov/, identifier NCT04293562.

Treatment Strategies for Cardiomyopathy in Children: A Scientific Statement From the American Heart Association

This scientific statement from the American Heart Association focuses on treatment strategies and modalities for cardiomyopathy (heart muscle disease) in children and serves as a companion scientific statement for the recent statement on the classification and diagnosis of cardiomyopathy in children. We propose that the foundation of treatment of pediatric cardiomyopathies is based on these principles applied as personalized therapy for children with cardiomyopathy: (1) identification of the specific cardiac pathophysiology; (2) determination of the root cause of the cardiomyopathy so that, if applicable, cause-specific treatment can occur (precision medicine); and (3) application of therapies based on the associated clinical milieu of the patient. These clinical milieus include patients at risk for developing cardiomyopathy (cardiomyopathy phenotype negative), asymptomatic patients with cardiomyopathy (phenotype positive), patients with symptomatic cardiomyopathy, and patients with end-stage cardiomyopathy. This scientific statement focuses primarily on the most frequent phenotypes, dilated and hypertrophic, that occur in children. Other less frequent cardiomyopathies, including left ventricular noncompaction, restrictive cardiomyopathy, and arrhythmogenic cardiomyopathy, are discussed in less detail. Suggestions are based on previous clinical and investigational experience, extrapolating therapies for cardiomyopathies in adults to children and noting the problems and challenges that have arisen in this experience. These likely underscore the increasingly apparent differences in pathogenesis and even pathophysiology in childhood cardiomyopathies compared with adult disease. These differences will likely affect the utility of some adult therapy strategies. Therefore, special emphasis has been placed on cause-specific therapies in children for prevention and attenuation of their cardiomyopathy in addition to symptomatic treatments. Current investigational strategies and treatments not in wide clinical practice, including future direction for investigational management strategies, trial designs, and collaborative networks, are also discussed because they have the potential to further refine and improve the health and outcomes of children with cardiomyopathy in the future.

Primary cardioprotection with dexrazoxane in patients with childhood cancer who are expected to receive anthracyclines: recommendations from the International Late Effects of Childhood Cancer Guideline Harmonization Group

Survivors of childhood cancer are at risk of anthracycline-induced cardiotoxicity, which might be prevented by dexrazoxane. However, concerns exist about the safety of dexrazoxane, and little guidance is available on its use in children. To facilitate global consensus, a working group within the International Late Effects of Childhood Cancer Guideline Harmonization Group reviewed the existing literature and used evidence-based methodology to develop a guideline for dexrazoxane administration in children with cancer who are expected to receive anthracyclines. Recommendations were made in consideration of evidence supporting the balance of potential benefits and harms, and clinical judgement by the expert panel. Given the dose-dependent risk of anthracycline-induced cardiotoxicity, we concluded that the benefits of dexrazoxane probably outweigh the risk of subsequent neoplasms when the cumulative doxorubicin or equivalent dose is at least 250 mg/m² (moderate recommendation). No recommendation could be formulated for cumulative doxorubicin or equivalent doses of lower than 250 mg/m², due to insufficient evidence to determine whether the risk of cardiotoxicity outweighs the possible risk of subsequent neoplasms. Further research is encouraged to determine the long-term efficacy and safety of dexrazoxane in children with cancer.

Supportive care in pediatric acute myeloid leukemia:Expert-based recommendations of the NOPHO-DB-SHIP consortium

INTRODUCTION

Pediatric acute myeloid leukemia (AML) is the second most common type of pediatric leukemia. Patients with AML are at high risk for several complications such as infections, typhlitis, and acute and long-term cardiotoxicity. Despite this knowledge, there are no definite supportive care guidelines as to what the best approach is to manage or prevent these complications.

AREA COVERED

The NOPHO-DB-SHIP (Nordic-Dutch-Belgian-Spain-Hong-Kong-Israel-Portugal) consortium, in preparation for a new trial in pediatric AML patients, had dedicated meetings for supportive care. In this review, the authors discuss the available data and outline recommendations for the management of children and adolescents with AML with an emphasis on hyperleukocytosis, tumor lysis syndrome, coagulation abnormalities and bleeding, infection, typhlitis, malnutrition, cardiotoxicity, and fertility preservation.

EXPERT OPINION

Improved supportive care has significantly contributed to increased cure rates. Recommendations on supportive care are an essential part of treatment for this highly susceptible population and will further improve their outcome.

Dexrazoxane for preventing or reducing cardiotoxicity in adults and children with cancer receiving anthracyclines

BACKGROUND

This review is the third update of a previously published Cochrane Review. The original review, looking at all possible cardioprotective agents, was split and this part now focuses on dexrazoxane only. Anthracyclines are effective chemotherapeutic agents in the treatment of numerous malignancies. Unfortunately, their use is limited by a dose-dependent cardiotoxicity. In an effort to prevent or reduce this cardiotoxicity, different cardioprotective agents have been studied, including dexrazoxane.

OBJECTIVES

To assess the efficacy of dexrazoxane to prevent or reduce cardiotoxicity and determine possible effects of dexrazoxane on antitumour efficacy, quality of life and toxicities other than cardiac damage in adults and children with cancer receiving anthracyclines when compared to placebo or no additional treatment.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to May 2021. We also handsearched reference lists, the proceedings of relevant conferences and ongoing trials registers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which dexrazoxane was compared to no additional therapy or placebo in adults and children with cancer receiving anthracyclines.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, data extraction, risk of bias and GRADE assessment of included studies. We analysed results in adults and children separately. We performed analyses according to the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

For this update, we identified 548 unique records. We included three additional RCTs: two paediatric and one adult. Therefore, we included a total of 13 eligible RCTs (five paediatric and eight adult). The studies enrolled 1252 children with leukaemia, lymphoma or a solid tumour and 1269 participants, who were mostly diagnosed with breast cancer. In adults, moderate-quality evidence showed that there was less clinical heart failure with the use of dexrazoxane (risk ratio (RR) 0.22, 95% confidence interval (CI) 0.11 to 0.43; 7 studies, 1221 adults). In children, we identified no difference in clinical heart failure risk between treatment groups (RR 0.20, 95% CI 0.01 to 4.19; 3 studies, 885 children; low-quality evidence). In three paediatric studies assessing cardiomyopathy/heart failure as the primary cause of death, none of the children had this outcome (1008 children, low-quality evidence). In the adult studies, different definitions for subclinical myocardial dysfunction and clinical heart failure combined were used, but pooled analyses were possible: there was a benefit in favour of the use of dexrazoxane (RR 0.37, 95% CI 0.24 to 0.56; 3 studies, 417 adults and RR 0.46, 95% CI 0.33 to 0.66; 2 studies, 534 adults, respectively, moderate-quality evidence). In the paediatric studies, definitions of subclinical myocardial dysfunction and clinical heart failure combined were incomparable, making pooling impossible. One paediatric study showed a benefit in favour of dexrazoxane (RR 0.33, 95% CI 0.13 to 0.85; 33 children; low-quality evidence), whereas another study showed no difference between treatment groups (Fischer exact P = 0.12; 537 children; very low-quality evidence). Overall survival (OS) was reported in adults and overall mortality in children. The meta-analyses of both outcomes showed no difference between treatment groups (hazard ratio (HR) 1.04, 95% 0.88 to 1.23; 4 studies; moderate-quality evidence; and HR 1.01, 95% CI 0.72 to 1.42; 3 studies, 1008 children; low-quality evidence, respectively). Progression-free survival (PFS) was only reported in adults. We subdivided PFS into three analyses based on the comparability of definitions, and identified a longer PFS in favour of dexrazoxane in one study (HR 0.62, 95% CI 0.43 to 0.90; 164 adults; low-quality evidence). There was no difference between treatment groups in the other two analyses (HR 0.95, 95% CI 0.64 to 1.40; 1 study; low-quality evidence; and HR 1.18, 95% CI 0.97 to 1.43; 2 studies; moderate-quality evidence, respectively). In adults, there was no difference in tumour response rate between treatment groups (RR 0.91, 95% CI 0.79 to 1.04; 6 studies, 956 adults; moderate-quality evidence). We subdivided tumour response rate in children into two analyses based on the comparability of definitions, and identified no difference between treatment groups (RR 1.01, 95% CI 0.95 to 1.07; 1 study, 206 children; very low-quality evidence; and RR 0.92, 95% CI 0.84 to 1.01; 1 study, 200 children; low-quality evidence, respectively). The occurrence of secondary malignant neoplasms (SMN) was only assessed in children. The available and worst-case analyses were identical and showed a difference in favour of the control group (RR 3.08, 95% CI 1.13 to 8.38; 3 studies, 1015 children; low-quality evidence). In the best-case analysis, the direction of effect was the same, but there was no difference between treatment groups (RR 2.51, 95% CI 0.96 to 6.53; 4 studies, 1220 children; low-quality evidence). For other adverse effects, results also varied. None of the studies evaluated quality of life. If not reported, the number of participants for an analysis was unclear.

AUTHORS' CONCLUSIONS

Our meta-analyses showed the efficacy of dexrazoxane in preventing or reducing cardiotoxicity in adults treated with anthracyclines. In children, there was a difference between treatment groups for one cardiac outcome (i.e. for one of the definitions used for clinical heart failure and subclinical myocardial dysfunction combined) in favour of dexrazoxane. In adults, no evidence of a negative effect on tumour response rate, OS and PFS was identified; and in children, no evidence of a negative effect on tumour response rate and overall mortality was identified. The results for adverse effects varied. In children, dexrazoxane may be associated with a higher risk of SMN; in adults this was not addressed. In adults, the quality of the evidence ranged between moderate and low; in children, it ranged between low and very low. Before definitive conclusions on the use of dexrazoxane can be made, especially in children, more high-quality research is needed. We conclude that if the risk of cardiac damage is expected to be high, it might be justified to use dexrazoxane in children and adults with cancer who are treated with anthracyclines. However, clinicians and patients should weigh the cardioprotective effect of dexrazoxane against the possible risk of adverse effects, including SMN, for each individual. For children, the International Late Effects of Childhood Cancer Guideline Harmonization Group has developed a clinical practice guideline.

Leveraging Clinical Trial Populations and Data from the Children's Oncology Group for Cancer Survivorship Research

Children and adolescents diagnosed with cancer can now expect an average 85% 5-year overall survival, with significant improvements in longer-term morbidity and mortality reported over the past several decades. However, the long-term impact of therapeutic agents and modalities introduced in recent years remains unclear and will require dedicated follow-up in the years ahead. The Children's Oncology Group (COG), a part of the NCI's National Clinical Trials Network, with over 200 sites across North America and beyond, enrolls more than 10,000 patients onto research protocols annually, inclusive of first-line clinical trials and nontherapeutic studies. COG provides a platform to conduct survivorship research with several unique strengths: (i) a huge catchment to ascertain relatively rare but important adverse events, (ii) study populations that are otherwise too rare to study in smaller consortia, including access to highly diverse patient populations, (iii) long-term follow-up of clinical trial populations linked to the original trial data, and (iv) a natural platform for intervention research. Enhancements in COG infrastructure facilitate survivorship research, including a COG patient registry (Project:EveryChild), availability of a long-term follow-up tracking resource, and successful deployment of various remote-based study procedures to reduce the burden on participants and participating institutions.

Anthracycline-induced cardiotoxicity: From pathobiology to identification of molecular targets for nuclear imaging

Anthracyclines are a widely used class of chemotherapy in pediatric and adult cancers, however, their use is hampered by the development of cardiotoxic side-effects and ensuing complications, primarily heart failure. Clinically used imaging modalities to screen for cardiotoxicity are mostly echocardiography and occasionally cardiac magnetic resonance imaging. However, the assessment of diastolic and global or segmental systolic function may not be sensitive to detect subclinical or early stages of cardiotoxicity. Multiple studies have scrutinized molecular nuclear imaging strategies to improve the detection of anthracycline-induced cardiotoxicity. Anthracyclines can activate all forms of cell death in cardiomyocytes. Injury mechanisms associated with anthracycline usage include apoptosis, necrosis, autophagy, ferroptosis, pyroptosis, reactive oxygen species, mitochondrial dysfunction, as well as cardiac fibrosis and perturbation in sympathetic drive and myocardial blood flow; some of which have been targeted using nuclear probes. This review retraces the pathobiology of anthracycline-induced cardiac injury, details the evidence to date supporting a molecular nuclear imaging strategy, explores disease mechanisms which have not yet been targeted, and proposes a clinical strategy incorporating molecular imaging to improve patient management.

Cardioprotection of High-Risk Individuals

Targeting cardioprotective strategies to patients at the highest risk for cardiac events can help maximize therapeutic benefits. Dexrazoxane, liposomal formulations, continuous infusions, and neurohormonal antagonists may be useful for cardioprotection for anthracycline-treated patients at the highest risk for heart failure. Prevalent cardiovascular disease is a risk factor for cardiac events with many cancer therapies, including anthracyclines, anti-human-epidermal growth factor receptor-2 therapy, radiation, and BCR-Abl tyrosine kinase inhibitors, and may be a risk factor for cardiac events with other therapies. Although evidence for cardioprotective strategies is sparse for nonanthracycline therapies, optimizing cardiac risk factors and prevalent cardiovascular disease may improve outcomes.

Rationale and Design of the Cardiac CARE Trial: A Randomized Trial of Troponin-Guided Neurohormonal Blockade for the Prevention of Anthracycline Cardiotoxicity

BACKGROUND

Anthracyclines are effective cytotoxic drugs used in the treatment of breast cancer and lymphoma but are associated with myocardial injury, left ventricular dysfunction, and heart failure. Anthracycline-induced cardiotoxicity is highly variable in severity and without a proven therapeutic intervention. β-Adrenergic receptor blockers and renin-angiotensin-system inhibitor therapies have been associated with modest cardioprotective effects in unselected patients.

METHODS

The Cardiac CARE trial is a multicentre prospective randomized open-label blinded end point trial of combination β-adrenergic receptor blocker and renin-angiotensin-system inhibitor therapy in patients with breast cancer and non-Hodgkin lymphoma receiving anthracycline chemotherapy that is associated with myocardial injury. Patients at higher risk of cardiotoxicity with plasma high-sensitivity cTnI (cardiac troponin I) concentrations in the upper tertile at the end of chemotherapy are randomized to standard of care plus combination candesartan and carvedilol therapy or standard of care alone. All patients undergo cardiac magnetic resonance imaging before and 6 months after anthracycline treatment. The primary end point is the change in left ventricular ejection fraction at 6 months after chemotherapy. In low-risk nonrandomized patients, left ventricular ejection fraction before and 6 months after anthracycline will be compared with define the specificity of the high-sensitivity cTnI assay for identifying low-risk participants who do not develop left ventricular systolic dysfunction.

DISCUSSION

Cardiac CARE will examine whether cardiac biomarker monitoring identifies patients at risk of left ventricular dysfunction following anthracycline chemotherapy and whether troponin-guided treatment with combination candesartan and carvedilol therapy prevents the development of left ventricular dysfunction in these high-risk patients.

Late health outcomes after dexrazoxane treatment: A report from the Children's Oncology Group

BACKGROUND

The objective of this study was to examine long-term outcomes among children newly diagnosed with cancer who were treated in dexrazoxane-containing clinical trials.

METHODS

P9404 (acute lymphoblastic leukemia/lymphoma [ALL]), P9425 and P9426 (Hodgkin lymphoma), P9754 (osteosarcoma), and Dana-Farber Cancer Institute 95-01 (ALL) enrolled 1308 patients between 1996 and 2001: 1066 were randomized (1:1) to doxorubicin with or without dexrazoxane, and 242 (from P9754) were nonrandomly assigned to receive dexrazoxane. Trial data were linked with the National Death Index, the Organ Procurement and Transplantation Network, the Pediatric Health Information System (PHIS), and Medicaid. Osteosarcoma survivors from the Childhood Cancer Survivor Study (CCSS; n = 495; no dexrazoxane) served as comparators in subanalyses. Follow-up events were assessed with cumulative incidence, Cox regression, and Fine-Gray methods.

RESULTS

In randomized trials (cumulative prescribed doxorubicin dose, 100-360 mg/m2 ; median follow-up, 18.6 years), dexrazoxane was not associated with relapse (hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.63-1.13), second cancers (HR, 1.19; 95% CI, 0.62-2.30), all-cause mortality (HR, 1.07; 95% CI, 0.78-1.47), or cardiovascular mortality (HR, 1.45; 95% CI, 0.41-5.16). Among P9754 patients (all exposed to dexrazoxane; cumulative doxorubicin, 450-600 mg/m2 ; median follow-up, 16.6-18.4 years), no cardiovascular deaths or heart transplantation occurred. The 20-year heart transplantation rate among CCSS osteosarcoma survivors (mean doxorubicin, 377 ± 145 mg/m2 ) was 1.6% (vs 0% in P9754; P = .13). Among randomized patients, serious cardiovascular outcomes (cardiomyopathy, ischemic heart disease, and stroke) ascertained by PHIS/Medicaid occurred less commonly with dexrazoxane (5.6%) than without it (17.6%; P = .02), although cardiomyopathy rates alone did not differ (4.4% vs 8.1%; P = .35).

CONCLUSIONS

Dexrazoxane did not appear to adversely affect long-term mortality, event-free survival, or second cancer risk.

Current State of Pediatric Cardio-Oncology: A Review

The landscape of pediatric oncology has dramatically changed over the course of the past several decades with five-year survival rates surpassing 80%. Anthracycline therapy has been the cornerstone of many chemotherapy regimens for pediatric patients since its introduction in the 1960s, and recent improved survival has been in large part due to advancements in chemotherapy, refinement of supportive care treatments, and development of novel therapeutics such as small molecule inhibitors, chimeric antigen receptor T-cell therapy, and immune checkpoint inhibitors. Unfortunately, many cancer-targeted therapies can lead to acute and chronic cardiovascular pathologies. The range of cardiotoxicity can vary but includes symptomatic or asymptotic heart failure, arrhythmias, coronary artery disease, valvar disease, pericardial disease, hypertension, and peripheral vascular disease. There is lack of data guiding primary prevention and treatment strategies in the pediatric population, which leads to substantial practice variability. Several important future research directions have been identified, including as they relate to cardiac disease, prevention strategies, management of cardiovascular risk factors, risk prediction, early detection, and the role of genetic susceptibility in development of cardiotoxicity. Continued collaborative research will be key in advancing the field. The ideal model for pediatric cardio-oncology is a proactive partnership between pediatric cardiologists and oncologists in order to better understand, treat, and ideally prevent cardiac disease in pediatric oncology patients.

Neuraminidase1 Inhibitor Protects Against Doxorubicin-Induced Cardiotoxicity via Suppressing Drp1-Dependent Mitophagy

Anthracyclines, such as doxorubicin (DOX), are among the effective chemotherapeutic drugs for various malignancies. However, their clinical use is limited by irreversible cardiotoxicity. This study sought to determine the role of neuraminidase 1 (NEU1) in DOX-induced cardiomyopathy and the potential cardio-protective effects of NEU1 inhibitor oseltamivir (OSE). Male Sprague–Dawley (SD) rats were randomized into three groups: control, DOX, and DOX + OSE. NEU1 was highly expressed in DOX-treated rat heart tissues compared with the control group, which was suppressed by OSE administration. Rats in the DOX + OSE group showed preserved cardiac function and were protected from DOX-induced cardiomyopathy. The beneficial effects of OSE were associated with the suppression of dynamin-related protein 1 (Drp1)-dependent mitochondrial fission and mitophagy. In detail, the elevated NEU1 in cardiomyocytes triggered by DOX increased the expression of Drp1, which subsequently enhanced mitochondrial fission and PINK1/Parkin pathway-mediated mitophagy, leading to a maladaptive feedback circle towards myocardial apoptosis and cell death. OSE administration selectively inhibited the increased NEU1 in myocardial cells insulted by DOX, followed by reduction of Drp1 expression, inhibition of PINK1 stabilization on mitochondria, and Parkin translocation to mitochondria, thus alleviating excessive mitochondrial fission and mitophagy, alleviating subsequent development of cellular apoptotic process. This work identified NEU1 as a crucial inducer of DOX-induced cardiomyopathy by promoting Drp1-dependent mitochondrial fission and mitophagy, and NEU1 inhibitor showed new indications of cardio-protection against DOX cardiotoxicity.

Mitochondrial Dynamin-Related Protein Drp1: a New Player in Cardio-oncology

PURPOSE OF REVIEW

This study is aimed at reviewing the recent progress in Drp1 inhibition as a novel approach for reducing doxorubicin-induced cardiotoxicity and for improving cancer treatment.

RECENT FINDINGS

Anthracyclines (e.g. doxorubicin) are one of the most common and effective chemotherapeutic agents to treat a variety of cancers. However, the clinical usage of doxorubicin has been hampered by its severe cardiotoxic side effects leading to heart failure. Mitochondrial dysfunction is one of the major aetiologies of doxorubicin-induced cardiotoxicity. The morphology of mitochondria is highly dynamic, governed by two opposing processes known as fusion and fission, collectively known as mitochondrial dynamics. An imbalance in mitochondrial dynamics is often reported in tumourigenesis which can lead to adaptive and acquired resistance to chemotherapy. Drp1 is a key mitochondrial fission regulator, and emerging evidence has demonstrated that Drp1-mediated mitochondrial fission is upregulated in both cancer cells to their survival advantage and injured heart tissue in the setting of doxorubicin-induced cardiotoxicity. Effective treatment to prevent and mitigate doxorubicin-induced cardiotoxicity is currently not available. Recent advances in cardio-oncology have highlighted that Drp1 inhibition holds great potential as a targeted mitochondrial therapy for doxorubicin-induced cardiotoxicity.

Minimizing cardiac toxicity in children with acute myeloid leukemia

Anthracycline chemotherapy remains an integral component of modern pediatric acute myeloid leukemia (AML) regimens and is often delivered at high doses to maximize cancer survival. Unfortunately, high-dose anthracyclines are associated with a significant risk of cardiotoxicity, which may result in early and/or long-term left ventricular systolic dysfunction and heart failure. Moreover, the development of cardiotoxicity during pediatric AML therapy is associated with lower event-free and overall survival, which may be partially attributable to incomplete anthracycline delivery. A combined strategy of primary cardioprotection and close cardiac monitoring can maximize chemotherapy delivery while reducing the toxicity of intensive AML therapy. Primary cardioprotection using dexrazoxane reduces short-term cardiotoxicity without compromising cancer survival. Liposomal anthracycline formulations, which are under active investigation, have the potential to mitigate cardiotoxicity while also improving antitumor efficacy. Primary cardioprotective strategies may reduce but not eliminate the risk of cardiotoxicity; therefore, close cardiac monitoring is also needed. Standard cardiac monitoring consists of serial echocardiographic assessments for left ventricular ejection fraction decline. Global longitudinal strain has prognostic utility in cancer therapy-related cardiotoxicity and may be used as an adjunct assessment. Additional cardioprotective measures should be considered in response to significant cardiotoxicity; these include cardiac remodeling medications to support cardiac recovery and anthracycline dose interruption and/or regimen modifications. However, the withholding of anthracyclines should be limited to avoid compromising cancer survival. A careful approach to cardioprotection during AML therapy is critical to maximize the efficacy of leukemia treatment while minimizing the short- and long-term risks of cardiotoxicity.

Cardiometabolic risk in childhood cancer survivors: a report from the Children's Oncology Group

BACKGROUND

Childhood cancer survivors are at risk for cardiovascular disease. We assessed the burden of potentially modifiable cardiometabolic risk factors (CRFs) among survivors compared with population-matched controls.

METHODS

Survivors previously enrolled on Pediatric Oncology Group protocols 9404, 9425, 9426, 9754, and DFCI 95-01 from 1996-2001 with acute lymphoblastic leukemia/lymphoma, Hodgkin lymphoma, or osteosarcoma were prospectively assessed for the prevalence of CRFs and compared with an age, sex, and race/ethnicity-matched 2013 NHANES population. We estimated future predicted cardiovascular risk based on general population (e.g. Framingham) and Childhood Cancer Survivor Study (CCSS) models.

RESULTS

Compared with NHANES (n=584), survivors (n=164; 44.5% female, median age 28 years [range: 16-38 years]; median 17.4 years [range: 13-22 years] since cancer diagnosis; median doxorubicin dose 300 mg/m2; 30.5% chest radiation) had similar rates of obesity, diabetes, and dyslipidemia, but more pre-hypertension/hypertension (38.4% vs. 30.1%, p=0.044). Survivors had fewer metabolic syndrome features compared with NHANES (2 or more features: 26.7% vs. 55.9%; p<0.001). Survivors were more physically active and smoked tobacco less (both p<0.0001). Therefore, general population cardiovascular risk scores were lower for survivors vs. NHANES. However, with CCSS models, 30.5% of survivors were at moderate risk of ischemic heart disease, and >95% at moderate/high risk for heart failure, with a 9-12% predicted incidence of these conditions by age 50 years.

CONCLUSIONS

Childhood cancer survivors exhibited similar or better cardiometabolic and lifestyle profiles compared with NHANES, but nonetheless are at risk for future clinically-significant cardiovascular disease.

IMPACT

Further strategies supporting optimal CRF control are warranted in survivors.

Interim Analysis of the Phase II Study: Noninferiority Study of Doxorubicin with Upfront Dexrazoxane plus Olaratumab for Advanced or Metastatic Soft-Tissue Sarcoma

PURPOSE

To report the interim analysis of the phase II single-arm noninferiority trial, testing the upfront use of dexrazoxane with doxorubicin on progression-free survival (PFS) and cardiac function in soft-tissue sarcoma (STS).

PATIENTS AND METHODS

Patients with metastatic or unresectable STS who were candidates for first-line treatment with doxorubicin were deemed eligible. An interim analysis was initiated after 33 of 65 patients were enrolled. Using the historical control of 4.6 months PFS for doxorubicin in the front-line setting, we tested whether the addition of dexrazoxane affected the efficacy of doxorubicin in STS. The study was powered so that a decrease of PFS to 3.7 months would be considered noninferior. Secondary aims included cardiac-related mortality, incidence of heart failure/cardiomyopathy, and expansion of cardiac monitoring parameters including three-dimensional echocardiography. Patients were allowed to continue on doxorubicin beyond 600 mg/m2 if they were deriving benefit and were not demonstrating evidence of symptomatic cardiac dysfunction.

RESULTS

At interim analysis, upfront use of dexrazoxane with doxorubicin demonstrated a PFS of 8.4 months (95% confidence interval: 5.1-11.2 months). Only 3 patients were removed from study for cardiotoxicity, all on > 600 mg/m2 doxorubicin. No patients required cardiac hospitalization or had new, persistent cardiac dysfunction with left ventricular ejection fraction remaining below 50%. The median administered doxorubicin dose was 450 mg/m2 (interquartile range, 300-750 mg/m2).

CONCLUSIONS

At interim analysis, dexrazoxane did not reduce PFS in patients with STS treated with doxorubicin. Involvement of cardio-oncologists is beneficial for the monitoring and safe use of high-dose anthracyclines in STS.See related commentary by Benjamin and Minotti, p. 3809.

Oxidative stress and inflammation: determinants of anthracycline cardiotoxicity and possible therapeutic targets

Chemotherapy with anthracycline-based regimens remains a cornerstone of treatment of many solid and blood tumors but is associated with a significant risk of cardiotoxicity, which can manifest as asymptomatic left ventricular dysfunction or overt heart failure. These effects are typically dose-dependent and cumulative and may require appropriate screening strategies and cardioprotective therapies in order to minimize changes to anticancer regimens or even their discontinuation. Our current understanding of cardiac damage by anthracyclines includes a central role of oxidative stress and inflammation. The identification of these processes through circulating biomarkers or imaging techniques might then be helpful for early diagnosis and risk stratification. Furthermore, therapeutic strategies relieving oxidative stress and inflammation hold promise to prevent heart failure development or at least to mitigate cardiac damage, although further evidence is needed on their efficacy, either alone or as part of combination therapies with neurohormonal antagonists, which are the current adopted standard.

How I treat pediatric acute myeloid leukemia

Treatment outcomes for pediatric patients with acute myeloid leukemia (AML) have continued to lag behind outcomes reported for children with acute lymphoblastic leukemia (ALL), in part because of the heterogeneity of the disease, a paucity of targeted therapies, and the relatively slow development of immunotherapy compared to ALL. In addition, we have reached the limits of treatment intensity and, even with outstanding supportive care, it is highly unlikely that further intensification of conventional chemotherapy alone will impact relapse rates. However, comprehensive genomic analyses and a more thorough characterization of the leukemic stem cell have provided insights that should lead to tailored and more effective therapies in the near future. In addition, new therapies are finally emerging, including the BCL-2 inhibitor venetoclax, CD33 and CD123-directed chimeric antigen receptor T cell therapy, CD123-directed antibody therapy, and menin inhibitors. Here we present four cases to illustrate some of the controversies regarding the optimal treatment of children with newly diagnosed or relapsed AML.

Monitoring of Metabolic Syndrome and Cardiovascular Disease in Childhood Cancer Survivors

Advances in cancer treatment have significantly improved childhood cancer survival, although metabolic syndrome and cardiovascular disease are common long-term complications that may occur years after treatment. Childhood cancer survivors may not receive appropriate follow-up due to lack of communication between oncologists and primary care physicians, or, from lack of awareness of possible long-term metabolic and cardiovascular complications after cancer treatment. We, therefore, reviewed current evidence on long-term effects of cancer therapy, and appropriate monitoring for long-term treatment effects in childhood cancer survivors that could lead to early detection and prompt treatment to prevent future cardiovascular events.

Resolvin E1 protects against doxorubicin-induced cardiotoxicity by inhibiting oxidative stress, autophagy and apoptosis by targeting AKT/mTOR signaling

Doxorubicin (DOX)-induced cardiotoxicity impairs the quality of life of cancer patients during or after DOX treatment, and it is imperative to explore a novel strategy to address this problem. Resolvin E1 (RvE1) is derived from eicosapentaenoic acid (EPA), which has been reported to exert beneficial effects on DOX-induced oxidative stress in cardiomyocytes. This study was designed to investigate whether RvE1 protects against DOX-induced cardiotoxicity, and the underlying mechanism was explored. DOX (20 mg/kg, one injection, i.p.) was used to induce DOX-induced cardiotoxicity in C57BL/6 mice. At 5 days after DOX administration, the effect of RvE1 was assessed by measuring cardiac function, oxidative stress, autophagy and apoptosis in cardiac tissue. We used an AKT inhibitor and rapamycin to investigate the underlying mechanisms. Our results showed that RvE1 inhibited the DOX-induced decrease in body weight and heart weight, the reduction in left ventricular ejection fraction and fractional shortening, and the increase in lactate dehydrogenase, creatine kinase myocardial bound and cardiomyocyte vacuolization. Compared to the control group, the DOX group exhibited increased oxidative stress, autophagy and apoptosis in cardiac tissue, which were alleviated by treatment with RvE1. The AKT/mTOR signaling pathways were responsible for RvE1-mediated regulation of DOX-induced oxidative stress, autophagy and myocardial apoptosis. In conclusion, RvE1 protected against DOX-induced cardiotoxicity via the regulation of AKT/mTOR signaling.

Cardiac Disease in Childhood Cancer Survivors: Risk Prediction, Prevention, and Surveillance: JACC CardioOncology State-of-the-Art Review

Cardiac diseases in the growing population of childhood cancer survivors are of major concern. Cardiotoxicity as a consequence of anthracyclines and chest radiotherapy continues to be relevant in the modern treatment era. Mitoxantrone has emerged as an important treatment-related risk factor and evidence on traditional cardiovascular risk factors in childhood cancer survivors is accumulating. International surveillance guidelines have been developed with the aim to detect and manage cardiac diseases early and prevent symptomatic disease. There is growing interest in risk prediction models to individualize prevention and surveillance. This State-of-the-Art Review summarizes literature from a systematic PubMed search focused on cardiac diseases after treatment for childhood cancer. Here, we discuss the prevalence, risk factors, prevention, risk prediction, and surveillance of cardiac diseases in survivors of childhood cancer.

Effect of Dexrazoxane on Left Ventricular Systolic Function and Treatment Outcomes in Patients With Acute Myeloid Leukemia: A Report From the Children's Oncology Group

PURPOSE

To determine whether dexrazoxane provides effective cardioprotection during frontline treatment of pediatric acute myeloid leukemia (AML) without increasing relapse risk or noncardiac toxicities of the chemotherapy regimens.

PATIENTS AND METHODS

This was a multicenter study of all pediatric patients with AML without high allelic ratio FLT3/ITD treated in the Children's Oncology Group trial AAML1031 between 2011 and 2016. Median follow-up was 3.5 years. Dexrazoxane was administered at the discretion of treating physicians and documented at each course. Ejection fraction (EF) and shortening fraction (SF) were recorded after each course and at regular intervals in follow-up. Per protocol, anthracyclines were to be withheld if there was evidence of left ventricular systolic dysfunction (LVSD) defined as SF < 28% or EF < 55%. Occurrence of LVSD, trends in EF and SF, 5-year event-free survival (EFS) and overall survival (OS), and treatment-related mortality (TRM) were compared by dexrazoxane exposure.

RESULTS

A total of 1,014 patients were included in the analyses; 96 were exposed to dexrazoxane at every anthracycline course, and 918 were never exposed. Distributions of sex, age, race, presenting WBC count, risk group, treatment arm, and compliance with cardiac monitoring were similar for dexrazoxane-exposed and -unexposed patients. Dexrazoxane-exposed patients had significantly smaller EF and SF declines than unexposed patients across courses and a lower risk for LVSD (26.5% v 42.2%; hazard ratio, 0.55; 95% CI, 0.36 to 0.86; P = .009). Dexrazoxane-exposed patients had similar 5-year EFS (49.0% v 45.1%; P = .534) and OS (65.0% v 61.9%; P = .613) to those unexposed; however, there was a suggestion of lower TRM with dexrazoxane (5.7% v 12.7%; P = .068).

CONCLUSION

Dexrazoxane preserved cardiac function without compromising EFS and OS or increasing noncardiac toxicities. Dexrazoxane should be considered for cardioprotection during frontline treatment of pediatric AML.

Impact of chemotherapy cycles and intervals on outcomes of nonspinal Ewing sarcoma in adults: a real-world experience

BACKGROUND

Adult Ewing sarcoma (ES) is a rare disease, the optimal treatment model is unknown. This study aimed to retrospectively analyze treatment-related prognostic factors of nonspinal ES in Chinese adults.

METHODS

Eighty-one patients treated between January 2005 and December 2017 were included in the present study. Thirty-three (40.7%) presented with metastatic disease at diagnosis. Eight patients were submitted to primary surgery followed by chemotherapy, while 73 patients received chemotherapy before and after surgery and/or local radiotherapy. The chemotherapy regimen included 8-17 cycles of vincristine, doxorubicin, and cyclophosphamide (VDC) alternating with ifosfamide and etoposide (IE) every 3 weeks. Clinical outcomes and safety were analyzed.

RESULTS

VDC/IE chemotherapy was well tolerated in adult patients with ES. Multivariate Cox regression analyses revealed that chemotherapy of at least 12 cycles was a favorable independent prognostic factor of event-free survival (hazard ratio, 0.558; 95% confidence interval, 0.323-0.965; P = 0.037) and overall survival (hazard ratio, 0.424; 95% confidence interval, 0.240-0.748; P = 0.003). Similarly, a low frequency of chemotherapy delays was an independent prognostic factor of improved OS (hazard ratio, 0.438; 95% confidence interval, 0.217-0.887; P = 0.022).

CONCLUSION

Our study suggests that adults with ES should be treated with an aggressive multidisciplinary approach, intensive chemotherapy with adequate cycles and appropriate intervals can be recommended in this group.

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.

Effects of dexrazoxane on doxorubicin-related cardiotoxicity and second malignant neoplasms in children with osteosarcoma: a report from the Children's Oncology Group

Background

Dexrazoxane protects from lower-cumulative-dose doxorubicin cardiotoxicity, but the effect of dexrazoxane in children with sarcoma treated with higher-cumulative-dose doxorubicin is unknown.

Methods

We evaluated children with osteosarcoma (OS) on two Children's Oncology Group trials with higher dose doxorubicin (375-600 mg/m²) preceded by dexrazoxane (10:1 dexrazoxane:doxorubicin dosing). They were evaluated after the minimum expected treatment time (METT), defined as 28 weeks. Cardiotoxicity was identified by echocardiography and serum N-terminal pro-brain natriuretic peptide (NT-proBNP). Second malignant neoplasm (SMN) data was collected.

Results

All children had normal left ventricular (LV) systolic function as measured by LV fractional shortening and no heart failure. The end-diastolic septal thickness Z-scores (P < 0.01) and LV mass Z-scores (P < 0.01) were significantly smaller than normal for body-surface area in both sexes. The average LV mass Z-scores were significantly smaller for girls (P < 0.01) and marginally smaller for boys (P = 0.06). Girls had significantly smaller LV end-diastolic dimension Z-scores normalized to BSA (P < 0.01) compared to healthy controls and had significant increases in NT-proBNP. Four children developed SMNs as first events, a rate similar to historical controls.

Conclusions

Dexrazoxane prevented LV dysfunction and heart failure in children with OS receiving higher dose doxorubicin. However, LV structural changes were not fully prevented, especially in girls. As a result, hearts become abnormally small for body size, resulting in higher LV stress. Dexrazoxane did not increase the risk of SMN. Dexrazoxane should be used in this population, particularly for girls, to mitigate anthracycline-induced cardiotoxicity.

Trial registrations

ClinicalTrials.gov: NCT00003937 (P9754) registered 1 Nov 1999, and NCT00023998 (AOST0121) registered 13 Sept 2001.

Closing the survivorship gap in children and adolescents with Hodgkin lymphoma

The treatment of Hodgkin lymphoma (HL) is one of early success. However, disease-free survival (DFS) does not reflect latent organ injury and its impact on health status and well-being beyond 5 years. In fact, we are at a crossroads, in terms of needing individualized approaches to maintain DFS, while minimizing late effects and preserving health-related quality of life (HRQoL). Premature morbidity and mortality translate to a high societal cost associated with the potential number of productive life years ahead in this population who are young at diagnosis. The discordance between short-term lymphoma-free survival and long-term health and HRQoL creates a "survivorship gap" which can be characterized for individuals and for subgroups of patients. The current review delineates contributors to compromised outcomes and health status in child and adolescent (paediatric) HL and frames the survivorship gap in terms of primary and secondary prevention. Primary prevention aims to titrate therapy. Secondary prevention entails strategies to intervene against late effects. Bridging the survivorship gap will be attained with enhanced knowledge of and attention to biology of the tumour and microenvironment, host genetic factors, HRQoL and sub-populations with disparate outcomes.

Efficacy of Dexrazoxane in Preventing Anthracycline Cardiotoxicity in Breast Cancer

Objectives

The authors performed a systematic review and meta-analysis of randomized and nonrandomized trials on the efficacy of dexrazoxane in patients with breast cancer who were treated with anthracyclines with or without trastuzumab.

Background

Breast cancer treatment with anthracyclines and trastuzumab is associated with an increased risk of cardiotoxicity. Among the various strategies to reduce the risk of cardiotoxicity, dexrazoxane is an option for primary prevention, but it is seldom used in clinical practice.

Methods

Online databases were searched from January 1990 up to March 1, 2019, for clinical trials on the use of dexrazoxane for the prevention of cardiotoxicity in patients with breast cancer receiving anthracyclines with or without trastuzumab. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model meta-analysis.

Results

Seven randomized trials and 2 retrospective trials with a total of 2,177 patients were included. Dexrazoxane reduced the risk of clinical heart failure (RR: 0.19; 95% CI: 0.09 to 0.40; p < 0.001) and cardiac events (RR: 0.36; 95% CI: 0.27 to 0.49; p < 0.001) irrespective of previous exposure to anthracyclines. The rate of a partial or complete oncological response, overall survival, and progression-free survival were not affected by dexrazoxane.

Conclusions

Dexrazoxane reduced the risk of clinical heart failure and cardiac events in patients with breast cancer undergoing anthracycline chemotherapy with or without trastuzumab and did not significantly impact cancer outcomes. However, the quality of available evidence is low, and further randomized trials are warranted before the systematic implementation of this therapy in clinical practice.

Echocardiographic long-term follow-up of adult survivors of pediatric cancer treated with Dexrazoxane-Anthracyclines association

AIMS

Cardiovascular disease is a well-recognized cause of increased late morbidity and mortality among survivors of childhood cancer treated with anthracyclines. Co-administration of Dexrazoxane has been shown to significantly reduce short-term and mid-term cardiotoxicity. Aim of this study was to assess cardiac function in long-term (>10 years) survivors of childhood tumors treated with dexrazoxane/anthracycline association.

METHODS AND RESULTS

Twenty cancer survivors previously treated with co-administration of anthracyclines-dexrazoxane for childhood renal tumors or sarcoma and a control group of 20 healthy subjects were enrolled in the study. Echocardiographic measurements included 3D left ventricular (LV) ejection fraction (LVEF) and LV and right ventricular (RV) global longitudinal strain (GLS). Among cancer survivors group the median age at diagnosis was 5 years (1-17) and they were evaluated at median follow-up time of 21.5 years (10-26). No evidence of cardiac toxicity, as defined by current guidelines, was reported in all survivors. No significant differences in standard and deformation imaging parameters were observed between survivors and controls (3D LVEF 58 ± 3% vs 60 ± 5% p = NS; LV GLS -21 ± 1% vs -21 ± 2% p = NS; RV GLS -23 ± 2% vs -23 ± 5% p = NS). No second tumor was registered in dexrazoxane-treated survivors.

CONCLUSIONS

Our findings may support the role of dexrazoxane as a useful strategy for cardio-protection in children undergoing anthracycline based treatment. However, large randomized trials are needed to confirm the cardio-protective role of dexrazoxane in pediatric setting at long-term follow-up.

Pediatric Cardio-Oncology: Development of Cancer Treatment-Related Cardiotoxicity and the Therapeutic Approach to Affected Patients

OPINION STATEMENT

The past 5 decades have seen significant improvements in outcomes for pediatric patients with cancer. Unfortunately, children and adolescents who have been treated for cancer are five to six times more likely to develop cardiovascular disease as a result of their therapies. Cardiovascular disease may manifest in a plethora of ways, from asymptomatic ventricular dysfunction to end-stage heart failure, hypertension, arrhythmia, valvular disease, early coronary artery disease, or peripheral vascular disease. A number of treatment modalities are implicated in pediatric and adult populations, including anthracyclines, radiation therapy, alkylating agents, targeted cancer therapies (small molecules and antibody therapies), antimetabolites, antimicrotubule agents, immunotherapy, interleukins, and chimeric antigen receptor T cells. For some therapies, such as anthracyclines, the mechanism of injury is elucidated, but for many others it is not. While a few protective strategies exist, in many cases, observation and close monitoring is the only defense against developing end-stage cardiovascular disease. Because of the variety of potential outcomes after cancer therapy, a one-size-fits-all approach is not appropriate. Rather, a good working relationship between oncology and cardiology to assess the risks and benefits of various therapies and planning for appropriate surveillance is the best model. When disease is identified, any of a number of therapies may be appropriate; however, in the pediatric and adolescent population supportive data are limited.

Leveraging the Cardio-Protective and Anticancer Properties of Resveratrol in Cardio-Oncology

Cardio-oncology is a clinical/scientific discipline which aims to prevent and/or treat cardiovascular diseases in cancer patients. Although a large number of cancer treatments are known to cause cardiovascular toxicity, they are still widely used because they are highly effective. Unfortunately, therapeutic interventions to prevent and/or treat cancer treatment-induced cardiovascular toxicity have not been established yet. A major challenge for such interventions is to protect the cardiovascular system without compromising the therapeutic benefit of anticancer medications. Intriguingly, the polyphenolic natural compound resveratrol and its analogs have been shown in preclinical studies to protect against cancer treatment-induced cardiovascular toxicity. They have also been shown to possess significant anticancer properties on their own, and to enhance the anticancer effect of other cancer treatments. Thus, they hold significant promise to protect the cardiovascular system and fight the cancer at the same time. In this review, we will discuss the current knowledge regarding the cardio-protective and the anticancer properties of resveratrol and its analogs. Thereafter, we will discuss the challenges that face the clinical application of these agents. To conclude, we will highlight important gaps of knowledge and future research directions to accelerate the translation of these exciting preclinical findings to cancer patient care.

Upfront dexrazoxane for the reduction of anthracycline-induced cardiotoxicity in adults with preexisting cardiomyopathy and cancer: a consecutive case series

BACKGROUND

Cardiotoxicity associated with anthracycline-based chemotherapies has limited their use in patients with preexisting cardiomyopathy or heart failure. Dexrazoxane protects against the cardiotoxic effects of anthracyclines, but in the USA and some European countries, its use had been restricted to adults with advanced breast cancer receiving a cumulative doxorubicin (an anthracycline) dose > 300 mg/m2. We evaluated the off-label use of dexrazoxane as a cardioprotectant in adult patients with preexisting cardiomyopathy, undergoing anthracycline chemotherapy.

METHODS

Between July 2015 and June 2017, five consecutive patients, with preexisting, asymptomatic, systolic left ventricular (LV) dysfunction who required anthracycline-based chemotherapy, were concomitantly treated with off-label dexrazoxane, administered 30 min before each anthracycline dose, regardless of cancer type or stage. Demographic, cardiovascular, and cancer-related outcomes were compared to those of three consecutive patients with asymptomatic cardiomyopathy treated earlier at the same hospital without dexrazoxane.

RESULTS

Mean age of the five dexrazoxane-treated patients and three patients treated without dexrazoxane was 70.6 and 72.6 years, respectively. All five dexrazoxane-treated patients successfully completed their planned chemotherapy (doxorubicin, 280 to 300 mg/m2). With dexrazoxane therapy, changes in LV systolic function were minimal with mean left ventricular ejection fraction (LVEF) decreasing from 39% at baseline to 34% after chemotherapy. None of the dexrazoxane-treated patients experienced symptomatic heart failure or elevated biomarkers (cardiac troponin I or brain natriuretic peptide). Of the three patients treated without dexrazoxane, two received doxorubicin (mean dose, 210 mg/m2), and one received daunorubicin (540 mg/m2). Anthracycline therapy resulted in a marked reduction in LVEF from 42.5% at baseline to 18%. All three developed symptomatic heart failure requiring hospitalization and intravenous diuretic therapy. Two of them died from cardiogenic shock and multi-organ failure.

CONCLUSION

The concomitant administration of dexrazoxane in patients with preexisting cardiomyopathy permitted successful delivery of anthracycline-based chemotherapy without cardiac decompensation. Larger prospective trials are warranted to examine the use of dexrazoxane as a cardioprotectant in patients with preexisting cardiomyopathy who require anthracyclines.

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.

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 safety of oncologic agents: a double-edged sword even in the era of targeted therapies - Part 2

INTRODUCTION

Patients with cancer are subject to the cardiotoxic effects of cancer therapy. Improved cancer treatments lead to more cancer-survivors, who though are exposed to various forms of cardiovascular (CV) disease (CVD) as they age. Aging patients are at increased risk of developing both malignancy and CVD or they may have survived some form of CVD as a result of effective CV treatments. Furthermore, patients with CVD may develop cancer and require treatment (and vice versa), all contributing to increased morbidity and mortality. The prevalence of both malignancy and CVD will increase due to the trend toward a longer lifespan.

AREAS COVERED

In part 2 of this review, the discussion of the CV effects of specific oncology drugs is completed with inclusion of additional immunological agents, current hormonal and other agents. Early detection and monitoring of cardiotoxicity, use of biomarkers and other imaging and diagnostic methods and prevention and treatment options are also discussed.

EXPERT OPINION

As outlined in part 1 of this review, oncologists need to be aware of the CV adverse-effects of their treatments and make careful and expectant clinical decisions, especially in patients with preexisting CVD or CV risk factors. Similarly, cardiologists should consider a detailed previous history of treatment for malignant disease, including prior chemotherapy exposure, dose(s) received, and/or combined modality therapy with chest radiotherapy. Both specialists should collaborate in order to minimize the impact of these two ubiquitous diseases (cancer and CVD) and mitigate the adverse effects of treatment modalities.

Humanin analog enhances the protective effect of dexrazoxane against doxorubicin-induced cardiotoxicity

The chemotherapeutic effect of doxorubicin (Dox) is limited by cumulative dose-dependent cardiotoxicity in cancer survivors. Dexrazoxane (DRZ) is approved to prevent Dox-induced cardiotoxicity. Humanin and its synthetic analog HNG have a cytoprotective effect on the heart. To investigate the cardioprotective efficacy of HNG alone or in combination with DRZ against Dox-induced cardiotoxicity, 80 adult male mice were randomly divided into 8 groups to receive the following treatments via intraperitoneal injection: saline dailym HNG (5 mg/kg) daily, DRZ (60 mg/kg) weekly, Dox (3 mg/kg) weekly, DRZ + HNG, Dox + HNG, Dox + DRZ, and Dox + HNG + DRZ. Echocardiograms were performed before and at 4, 8, and 9.5 wk after the beginning of treatment. All mice were euthanized at 10 wk. In the absence of Dox, HNG, DRZ, or DRZ + HNG had no adverse effect on the heart. Dox treatment caused decreases in ejection fraction and cardiac mass and increases in cardiomyocyte apoptosis and intracardiac fibrosis. HNG or DRZ alone blunted the Dox-induced decrease in left ventricle posterior wall thickness and modestly ameliorated the Dox-induced decrease in ejection fraction. HNG + DRZ significantly ameliorated Dox-induced decreases in ejection function, cardiac fibrosis, and cardiac mass. Using a targeted analysis for the mitochondrial gene array and protein expression in heart tissues, we demonstrated that HNG + DRZ reversed DOX-induced altered transcripts that were biomarkers of cardiac damage and uncoupling protein-2. We conclude that HNG enhances the cardiac protective effect of DRZ against Dox-induced cardiotoxicity. HNG + DRZ protects mitochondria from Dox-induced cardiac damage and blunts the onset of cardiac dysfunction. Thus, HNG may be an adjuvant to DRZ in preventing Dox-induced cardiotoxicity. NEW & NOTEWORTHY Doxorubicin (Dox) is commonly used for treating a wide range of human cancers. However, cumulative dosage-dependent carditoxicity often limits its clinical applications. We demonstrated in this study that treating young adult male mice with synthetic humanin analog enhanced the cardiac protective effect of dexrazoxane against chemotherapeutic agent Dox-induced cardiac dysfunction. Thus, humanin analog can potentially serve as an adjuvant to dexrazoxane in more effectively preventing Dox-induced cardiac dysfunction and cardiomyopathy.

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.

Risk-benefit of dexrazoxane for preventing anthracycline-related cardiotoxicity: re-evaluating the European labeling

Dexrazoxane can prevent anthracycline-associated cardiotoxicity. However, in 2011, its use in children was contraindicated by the EMA over concerns of increased risk of infection, myelosuppression and second primary malignancies, and because its efficacy in children had not then been established. We review here the evidence published since 2011, which confirms that dexrazoxane is an effective cardioprotectant in children and adolescents, is not associated with an increased risk of second primary malignancies or excess early or late mortality and does not impair chemotherapy efficacy. Based on this evidence, the contraindication for children and adolescents requiring high doses of anthracyclines and at risk for cardiotoxicity was removed from the European labeling for dexrazoxane.

An initial health economic evaluation of pharmacogenomic testing in patients treated for childhood cancer with anthracyclines

BACKGROUND

Anthracyclines are a class of highly effective chemotherapeutic drugs commonly used to treat cancer patients. Anthracyclines, however, are associated with the development of serious adverse reactions, including anthracycline-induced cardiotoxicity (ACT). It is not possible, within current practice, to accurately individualize treatment to minimize risk.

PROCEDURE

Recently, genetic variants have been associated with the risk of ACT in children. Building on these findings and the related genetic test, a predictive model was developed which classifies pediatric patients by their risk of developing ACT. We assessed the value of this ACT-predictive risk classification in addressing ACT.

RESULTS

With current care, the estimated average lifetime cost of ACT is $8,667 per anthracycline-treated patient and approximately 7% of patients are expected to die from ACT. The projected impact of the information from the new predictive model is a 17% reduction in the risk of mortality from ACT and savings of about 6%: lives saved and lower costs.

CONCLUSION

The newly identified genetic variants associated with the risk of ACT provide information that allows a more reliable prediction of the risk of ACT for a given patient and can be obtained at a very moderate cost, which is expected to lead to meaningful progress in reducing harm and costs associated with ACT.

A recommended practical approach to the management of anthracycline-based chemotherapy cardiotoxicity: an opinion paper of the working group on drug cardiotoxicity and cardioprotection, Italian Society of Cardiology

Anthracyclines are the mainstay of treatment of a variety of haematological malignancies and solid tumours. Unfortunately, the clinical use of these drugs is limited by cumulative, dose-related cardiotoxicity which may ultimately lead to a severe and irreversible form of cardiomyopathy. Thus, there is an increasing need for close cooperation among cardiologists, oncologists and haemato-oncologists. As anthracyclines save lives, the logical goal of this cooperation, besides preventing or mitigating cardiotoxicity, is to promote an acceptable balance between the potential cardiac side effects and the vital benefit of anticancer treatment. This manuscript, which is specifically addressed to the cardiologist who has not accumulated much experience in the field of cancer therapy, focuses on several topics, that is old and new mechanisms of cardiac toxicity, late cardiac toxicity, the importance of overall risk assessment, the key role of a cardiology consult before starting cancer therapy, and the pros and cons of primary and secondary prevention programmes.

State of the art review: Chemotherapy-induced cardiotoxicity in children

Chemotherapy-induced cardiotoxicity in adults and children is a topic with a growing interest in the cardiology literature. The ability to detect cardiac dysfunction in a timely manner is essential in order to begin adequate treatment and prevent further deterioration. This article aims to provide a review on the myocardial injury process, chemotherapeutic agents that lead to cardiotoxicity, the definition of cardiotoxicity, and the methods of timely detection and treatment.