Cardiac complications in childhood cancer survivors treated with anthracyclines

Sex-related differences in delayed doxorubicin-induced cardiac dysfunction in C57BL/6 mice

Cancer survivors may experience long-term cardiovascular complications due to chemotherapeutic drugs such as doxorubicin (DOX). The exact mechanism of delayed DOX-induced cardiotoxicity has not been fully elucidated. Sex is an important risk factor for DOX-induced cardiotoxicity. In the current study, we identified sex differences in delayed DOX-induced cardiotoxicity and determined the underlying molecular determinants of the observed sexual dimorphism. Five-week-old male and female mice were administered intraperitoneal injections of DOX (4 mg/kg/week) or saline for 6 weeks. Echocardiography was performed 5 weeks after the last dose of DOX to evaluate cardiac function. Thereafter, mice were sacrificed and gene expression of markers of apoptosis, senescence, and inflammation was measured by PCR in hearts and livers. Proteomic profiling of the heart from both sexes was conducted to determine differentially expressed proteins (DEPs). Only DOX-treated male, but not female, mice demonstrated cardiac dysfunction, cardiac atrophy, and upregulated cardiac expression of Nppb and Myh7. No sex-related differences were observed in DOX-induced expression of most apoptotic, senescence, and pro-inflammatory markers. However, the gene expression of Trp53 was significantly reduced in hearts of DOX-treated female mice only. The anti-inflammatory marker Il-10 was significantly reduced in hearts of DOX-treated male mice only, while the pro-inflammatory marker Il-1α was significantly reduced in livers of DOX-treated female mice only. Gene expression of Tnf-α was reduced in hearts of both DOX-treated male and female mice. Proteomic analysis identified several DEPs after DOX treatment in a sex-specific manner, including anti-inflammatory acute phase proteins. This is the first study to assess sex-specific proteomic changes in a mouse model of delayed DOX-induced cardiotoxicity. Our proteomic analysis identified several sexually dimorphic DEPs, many of which are associated with the anti-inflammatory marker Il-10.

Anthracycline-induced cardiotoxicity on regional myocardial work and left ventricular mechanical dispersion in adolescents and young adults in post-lymphoma remission

BACKGROUND

Myocardial work (MW) is a new echocardiographic tool with a high sensitivity to detect early and subtle alterations of myocardial function. We aimed to evaluate the late effects of anthracyclines by assessing the global and segmental MW and intraventricular mechanical dispersion from speckle tracking echocardiography in childhood lymphoma survivors (CLS).

METHODS

Thirty-one young adults including CLS and age-matched healthy controls were enrolled. All underwent echocardiography including an evaluation of left ventricular (LV) morphology and regional function. We assessed LV longitudinal (differentiating sub-endocardial and sub-epicardial layers), circumferential strains and twist, global and regional MW index (MWI). LV mechanical dispersion was assessed from the time dispersion of LV longitudinal strain, from myocardial wasted work (MWW) and myocardial work efficiency (MWE).

RESULTS

The longitudinal strains both at the level of the sub-endocardium and sub-epicardium were reduced in CLS compared to controls. The global MWI was also decreased (1668 ± 266 vs 1870 ± 264%.mmHg in CLS patients and controls, respectively, p < 0.05), especially on the apical segments. An increase of LV intraventricular mechanical dispersion was observed in CLS. MWW and MWE remained unchanged compared to controls.

CONCLUSION

Our results strongly support that cardiac remodeling is observed in CLS, characterized by a decrease in MW and an increase in LV mechanical dispersion. The apex is specifically altered, but its clinical significance remains uncertain. MW as a complement to strain seems interesting in cancer survivors to detect myocardial dysfunction at early stage and adapt their follow-up.

Association between genetic variants of transmembrane transporters and susceptibility to anthracycline-induced cardiotoxicity: Current understanding and existing evidence

Anthracyclines remain the cornerstone of numerous chemotherapeutic protocols, with beneficial effects against haematological malignancies and solid tumours. Unfortunately, the clinical usefulness of anthracyclines is compromised by the development of cardiotoxic side effects, leading to dose limitations or treatment discontinuation. There is no absolute linear correlation between the incidence of cardiotoxicity and the threshold dose, suggesting that genetic factors may modify the association between anthracyclines and cardiotoxicity risk. And the majority of single nucleotide polymorphisms (SNPs) associated with anthracycline pharmacogenomics were identified in the ATP-binding cassette (ABC) and solute carrier (SLC) transporters, generating increasing interest in the pharmacogenetic implications of their genetic variations for anthracycline-induced cardiotoxicity (AIC). This review focuses on the influence of SLC and ABC polymorphisms on AIC and highlights the prospects and clinical significance of pharmacogenetics for individualised preventive approaches.

Pharmacotherapy for Cancer Treatment-Related Cardiac Dysfunction and Heart Failure in Childhood Cancer Survivors

The number of childhood cancer survivors is increasing rapidly. According to American Association for Cancer Research, there are more than 750,000 childhood cancer survivors in the United States and Europe. As the number of childhood cancer survivors increases, so does cancer treatment-related cardiac dysfunction (CTRCD), leading to heart failure (HF). It has been reported that childhood cancer survivors who received anthracyclines are 15 times more likely to have late cancer treatment-related HF and have a 5-fold higher risk of death from cardiovascular (CV) disease than the general population. CV disease is the leading cause of death in childhood cancer survivors. The increasing need to manage cancer survivor patients has led to the rapid creation and adaptation of cardio-oncology. Cardio-oncology is a multidisciplinary science that monitors, treats, and prevents CTRCD. Many guidelines and position statements have been published to help diagnose and manage CTRCD, including those from the American Society of Clinical Oncology, the European Society of Cardiology, the Canadian Cardiovascular Society, the European Society of Medical Oncology, the International Late Effects of Childhood Cancer Guideline Harmonization Group, and many others. However, there remains a gap in identifying high-risk patients likely to develop cardiomyopathy and HF in later life, thus reducing primary and secondary measures being instituted, and when to start treatment when there is echocardiographic evidence of left ventricular (LV) dysfunctions without symptoms of HF. There are no randomized controlled clinical trials for treatment for CTRCD leading to HF in childhood cancer survivors. The treatment of HF due to cancer treatment is similar to the guidelines for general HF. This review describes the latest pharmacologic therapy for preventing and treating LV dysfunction and HF in childhood cancer survivors based on expert consensus guidelines and extrapolating data from adult HF trials.

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.

Cardiac Imaging in Childhood Cancer Survivors: A State-of-the-Art Review

Childhood cancer survival has improved significantly in the past few decades, reaching rates of 80% or more at 5 years. However, with improved survival, early- and late-occurring complications of chemotherapy and radiotherapy exposure are becoming progressively more evident. Cardiovascular diseases represent the leading cause of non-oncological morbidity and mortality in this highly vulnerable population. Therefore, the necessity of reliable, noninvasive screening tools able to early identify cardiac complications early is now pre-eminent in order to implement prevention strategies and mitigate disease progression. Echocardiography, may allow identification of myocardial dysfunction, pericardial complications, and valvular heart diseases. However, additional imaging modalities may be necessary in selected cases. This manuscript provides an in-depth review of noninvasive imaging parameters studied in childhood cancer survivors. Furthermore, we will illustrate brief surveillance recommendations according to available evidence and future perspectives in this expanding field.

Long-term in vitro recording of cardiac action potentials on microelectrode arrays for chronic cardiotoxicity assessment

The reliable identification of chronic cardiotoxic effects in in vitro screenings is fundamental for filtering out toxic molecular entities before in vivo animal experimentation and clinical trials. Present techniques such as patch-clamp, voltage indicators, and standard microelectrode arrays do not offer at the same time high sensitivity for measuring transmembrane ion currents and low-invasiveness for monitoring cells over long time. Here, we show that optoporation applied to microelectrode arrays enables measuring action potentials from human-derived cardiac syncytia for more than 1 continuous month and provides reliable data on chronic cardiotoxic effects caused by known compounds such as pentamidine. The technique has high potential for detecting chronic cardiotoxicity in the early phases of drug development.

Cardio-Oncology in Childhood: State of the Art

PURPOSE OF REVIEW

Cardio-oncology is an increasingly important field of cardiology that focuses on the detection, monitoring, and treatment of cardiovascular disease (CVD) occurring during and after oncological treatments. The survival rate for childhood cancer patients has dramatically increased thanks to new treatment protocols and cardiovascular (CV) sequelae represent the third most frequent cause of mortality in surviving patients. This study aims to provide a complete and updated review of all the main aspects of cardio-oncology in childhood and to highlight the critical issues.

RECENT FINDINGS

The problem of CV complications in childhood cancer survivors raises the need to make an early diagnosis of cardiotoxicity by the new imaging and laboratory techniques in order to intervene promptly and to implement pharmacological strategies and lifestyle changes to reduce or even to prevent cardiac injury. Furthermore, a stratification of CV risk, also including new predisposing factors such as the presence of some genetic mutations, is of paramount importance before undertaking oncological treatments. Besides, a systematic and personalized planning of long-term follow-up is fundamental to ensure a transition from pediatric to adult hospital and to avoid missed or late diagnosis of cardiomyopathy. We reviewed the main risk factors for cardiotoxicity in children, both traditional and emerging ones: the mechanisms of toxicity of both old and new antineoplastic therapies, the techniques for detecting cardiac damage, and the current evidence regarding pharmacological cardioprotection. At the end, we focused our attention on the existing guidelines and strategies about the long-term follow-up of childhood cancer survivors.

Cardio-Oncology Recommendations for Pediatric Oncology Patients: An Australian and New Zealand Delphi Consensus

Cardio-oncology is a new multidisciplinary area of expertise that seeks to pre-emptively and proactively address cardiac complications that emerge during and following cancer therapy. Modern therapies including molecular targeted therapy and immunotherapy have broadened the agents that can cause cardiac sequelae, often with complications arising within days to weeks of therapy. Several international guidelines have been developed for the acute monitoring of cardio-oncology side effects. However, none are specific to pediatrics. We have addressed this gap in the literature by undertaking a rigorous Delphi consensus approach across 11 domains of cardio-oncology care using an Australian and New Zealand expert group. The expert group consisted of pediatric and adult cardiologists and pediatric oncologists. This Delphi consensus provides an approach to perform risk and baseline assessment, screening, and follow-up, specific to the cancer therapeutic. This review is a useful tool for clinicians involved in the cardio-oncology care of pediatric oncology patients.

Assessment of Cardiovascular Function in Childhood Leukemia Survivors: The Role of the Right Heart

Childhood acute lymphoblastic leukemia (ALL) survivors who underwent chemotherapy with anthracyclines have an increased cardiovascular risk. The aim of the study was to evaluate left and right cardiac chamber performances and vascular endothelial function in childhood ALL survivors. Fifty-four ALL survivors and 37 healthy controls were enrolled. All patients underwent auxological evaluation, blood pressure measurements, biochemical parameters of endothelial dysfunction, flow-mediated dilatation (FMD) of the brachial artery, mean common carotid intima-media thickness (c-IMT), antero-posterior diameter of the infra-renal abdominal aorta (APAO), and echocardiographic assessment. The ALL subjects had significantly lower FMD (p = 0.0041), higher left (p = 0.0057) and right (p = 0.0021) echocardiographic/Doppler Tei index (the non-invasive index for combined systolic and diastolic ventricular function) as compared to controls. Tricuspid annular plane excursion (TAPSE) was 16.9 ± 1.2 mm vs. 24.5 ± 3.7 mm, p < 0.0001. Cumulative anthracycline doses were related to TAPSE (p < 0.001). The ALL survivors treated with anthracyclines demonstrated systo/diastolic alterations of the right ventricle and reduced endothelial function compared with healthy controls. The early recognition of subclinical cardiac and vascular impairment during follow up is of utmost importance for the cardiologist to implement strategies preventing overt cardiovascular disease considering the growing number of young adults cured after childhood ALL.

Pharmacogenomics in drug-induced cardiotoxicity: Current status and the future

Drug-induced cardiotoxicity (DICT) is an important concern of drug safety in both drug development and clinical application. The clinical manifestations of DICT include cardiomyopathy, arrhythmia, myocardial ischemia, heart failure, and a series of cardiac structural and functional changes. The occurrence of DICT has negative impacts on the life quality of the patients, brings additional social and economic burden. It is important to identify the potential factors and explore the mechanisms of DICT. Traditional cardiovascular risk factors can only partially explain the risk of DICT. Pharmacogenomic studies show accumulated evidence of genetics in DICT and suggest the potential to guide precision therapy to reduce risk of cardiotoxicity. The comprehensive application of technologies such as third-generation sequencing, human induced pluripotent stem (iPS) cells and genome editing has promoted the in-depth understanding of the functional role of susceptible genes in DICT. This paper reviewed drugs that cause DICT, the clinical manifestations and laboratory tests, as well as the related content of genetic variations associated with the risk of DICT, and further discussed the implication of new technologies in pharmacogenomics of DICT.

Development and Characterization of a Mass Cytometry Panel for Detecting the Effect of Acute Doxorubicin Exposure on Murine Cardiac Non-myocytes

Childhood cancer survivors (CCSs) face lifelong side effects related to their treatment with chemotherapy. Anthracycline agents, such as doxorubicin (DOX), are important in the treatment of childhood cancers but are associated with cardiotoxicity. Cardiac toxicities represent a significant source of chronic disability that cancer survivors face; despite this, the chronic cardiotoxicity phenotype and how it relates to acute toxicity remains poorly defined., To address this critical knowledge gap, we studied the acute effect of DOX on murine cardiac non-myocytes in vivo. Determination of the acute cellular effects of DOX on non-myocytes, a cell pool with finite replicative capacity, provides a basis for understanding the pathogenesis of the chronic heart disease that CCSs face. To investigate the acute cellular effects of DOX, we present scRNAseq data from homeostatic cardiac non-myocytes and compare it to pre-existing datasets as well as a novel CyTOF datasets. SCANPY, a python-based single cell analysis, was used to assess the heterogeneity of cells detected in scRNAseq and CyTOF. To further assist in CyTOF data annotation, joint analyses of scRNAseq and CyTOF data using an artificial neural network known as sparse autoencoder for clustering, imputation, and embedding (SAUCIE) are performed. Lastly, the panel is tested on a mouse model of acute DOX exposure at two time points (24 and 72 hours) after the last dose of doxorubicin and examined with joint clustering. In sum, we report the first ever CyTOF study of cardiac non-myocytes and characterize the effect of acute DOX exposure with scRNAseq and CyTOF.

Chronic Cardiotoxicity Assays Using Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes (hiPSC-CMs)

Cardiomyocytes (CMs) differentiated from human induced pluripotent stem cells (hiPSCs) are increasingly used in cardiac safety assessment, disease modeling and regenerative medicine. A vast majority of cardiotoxicity studies in the past have tested acute effects of compounds and drugs; however, these studies lack information on the morphological or physiological responses that may occur after prolonged exposure to a cardiotoxic compound. In this review, we focus on recent advances in chronic cardiotoxicity assays using hiPSC-CMs. We summarize recently published literature on hiPSC-CMs assays applied to chronic cardiotoxicity induced by anticancer agents, as well as non-cancer classes of drugs, including antibiotics, anti-hepatitis C virus (HCV) and antidiabetic drugs. We then review publications on the implementation of hiPSC-CMs-based assays to investigate the effects of non-pharmaceutical cardiotoxicants, such as environmental chemicals or chronic alcohol consumption. We also highlight studies demonstrating the chronic effects of smoking and implementation of hiPSC-CMs to perform genomic screens and metabolomics-based biomarker assay development. The acceptance and wide implementation of hiPSC-CMs-based assays for chronic cardiotoxicity assessment will require multi-site standardization of assay protocols, chronic cardiac maturity marker reproducibility, time points optimization, minimal cellular variation (commercial vs. lab reprogrammed), stringent and matched controls and close clinical setting resemblance. A comprehensive investigation of long-term repeated exposure-induced effects on both the structure and function of cardiomyocytes can provide mechanistic insights and recapitulate drug and environmental cardiotoxicity.

Current Insights into the Management of Late Chemotherapy Toxicities in Pediatric Osteosarcoma Patients

With ever increasing long-term, disease free survival rates, long-term toxicities of otherwise successful therapy have gained increasing importance. They can be grouped into potentially life-threatening, especially secondary malignancies and anthracycline cardiomyopathies, potentially disabling, particularly severe hearing loss and renal insufficiency, other, and rare events. Pathophysiology, frequency, and medical treatment approaches are discussed. Finally, fertility issues and quality of life issues are discussed, together with an outlook into the future. The challenge to cure as many patients as possible from osteosarcoma while enabling a life free of late effects will remain.

Child development at 6 years after maternal cancer diagnosis and treatment during pregnancy

Background

Data on the long-term effects of prenatal exposure to maternal cancer and its treatment on child development are scarce.

Methods

In a multicenter cohort study, the neurologic and cardiac outcomes of 6-year-old children born to women diagnosed with cancer during pregnancy were compared with the outcome of children born after an uncomplicated pregnancy. Assessment included clinical evaluation, comprehensive neuropsychological testing, electrocardiography and echocardiography.

Results

In total, 132 study children and 132 controls were included. In the study group, 97 children (73.5%) were prenatally exposed to chemotherapy (alone or in combination with other treatments), 14 (10.6%) to radiotherapy (alone or in combination), 1 (0.8%) to trastuzumab, 12 (9.1%) to surgery alone and 16 (12.1%) to no treatment. Although within normal ranges, statistically significant differences were found in mean verbal IQ and visuospatial long-term memory, with lower scores in the study versus control group (98.1, 95% confidence interval [CI]: 94.5–101.8, versus 104.4, 95% CI: 100.4–108.4, P = 0.001, Q < 0.001 [Q refers to the false discovery rate adjusted P value], and 3.9, 95% CI: 3.6–4.3, versus 4.5, 95% CI: 4.1–4.9, P = 0.005, Q = 0.045, respectively). A significant difference in diastolic blood pressure was found, with higher values in chemotherapy-exposed (61.1, 95% CI: 59.0 to 63.2) versus control children (56.0, 95% CI 54.1 to 57.8) (P < 0.001, Q < 0.001) and in a subgroup of 59 anthracycline-exposed (61.8, 95% CI: 59.3 to 64.4) versus control children (55.9, 95% CI: 53.6 to 58.1) (P < 0.001, Q = 0.02).

Conclusions

Children prenatally exposed to maternal cancer and its treatment are at risk for lower verbal IQ and visuospatial long-term memory scores and for higher diastolic blood pressure, but other cognitive functions and cardiac outcomes were normal at the age of 6 years.

Clinical trial registration

The study is registered at ClinicalTrials.gov, NCT00330447.

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Cancer treatment including chemotherapy is possible during pregnancy.

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Children are at risk for lower verbal IQ and visuospatial long-term memory scores.

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Other cognitive functions and cardiac outcomes were normal at the age of 6 years.

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We documented ototoxicity in three children exposed to cisplatin.

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Follow-up until adulthood is recommended.

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.

Human Pluripotent Stem Cell-Derived Cardiomyocytes for Assessment of Anticancer Drug-Induced Cardiotoxicity

Cardiotoxicity is a major cause of high attrition rates among newly developed drugs. Moreover, anti-cancer treatment-induced cardiotoxicity is one of the leading reasons of mortality in cancer survivors. Cardiotoxicity screening in vitro may improve predictivity of cardiotoxicity by novel drugs, using human pluripotent stem cell (hPSC)-derived-cardiomyocytes. Anthracyclines, including Doxorubicin, are widely used and highly effective chemotherapeutic agents for the treatment of different forms of malignancies. Unfortunately, anthracyclines cause many cardiac complications early or late after therapy. Anthracyclines exhibit their potent anti-cancer effect primarily via induction of DNA damage during the DNA replication phase in proliferative cells. In contrast, studies in animals and hPSC-cardiomyocytes have revealed that cardiotoxic effects particularly arise from (1) the generation of oxidative stress inducing mitochondrial dysfunction, (2) disruption of calcium homeostasis, and (3) changes in transcriptome and proteome, triggering apoptotic cell death. To increase the therapeutic index of chemotherapeutic Doxorubicin therapy several protective strategies have been developed or are under development, such as (1) reducing toxicity through modification of Doxorubicin (analogs), (2) targeted delivery of anthracyclines specifically to the tumor tissue or (3) cardioprotective agents that can be used in combination with Doxorubicin. Despite continuous progress in the field of cardio-oncology, cardiotoxicity is still one of the major complications of anti-cancer therapy. In this review, we focus on current hPSC-cardiomyocyte models for assessing anthracycline-induced cardiotoxicity and strategies for cardioprotection. In addition, we discuss latest developments toward personalized advanced pre-clinical models that are more closely recapitulating the human heart, which are necessary to support in vitro screening platforms with higher predictivity. These advanced models have the potential to reduce the time from bench-to-bedside of novel antineoplastic drugs with reduced cardiotoxicity.

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.

Treatment for lymphoma and late cardiovascular disease risk: A systematic review and meta-analysis

BACKGROUND AND AIMS

Lymphoma patients are frequently treated with cancer therapies that may increase the risk of adverse health outcomes later in life, including cardiovascular disease (CVD) mortality. We sought to investigate the long-term risk of CVD incidence in this survivor population relative to the general population to quantify this health burden.

METHODS

A systematic review and meta-analysis was conducted using EMBASE, MEDLINE, and CINAHL databases, from date of inception to November 2016, with additional searches completed through June 2018. Included reports were observational studies assessing CVD incidence in patients of either Hodgkin or non-Hodgkin lymphoma (HL, NHL) who survived for at least 5 years from the time of diagnosis or if the study had a median follow-up of 10 years. Meta-analyses were performed using random effects models, and subgroup analyses were conducted to determine the incidence of specific CVD subtypes (coronary heart disease, pericardial disease, valvular heart disease, myocardial disease, cardiac dysrhythmia, and cerebrovascular disease). Heterogeneity was assessed using I 2 statistics and prediction intervals.

RESULTS

Of the 7734 studies identified, 22 studies were included in this review, representing 32 438 HL and NHL survivors. Relative to the general population, lymphoma survivors had statistically significant two to threefold increases in the risk for nearly all subtypes of CVD examined. Lymphoma survivors appeared to be particularly susceptible to pericardial diseases (HL: 10.67, 95% confidence interval (CI), 7.75-14.69; NHL: 4.70, 95% CI, 2.08-10.61) and valvular diseases (HL: 13.10, 95% CI, 7.41-23.16; NHL: 3.76, 95% CI, 2.12-6.66). Although the 95% CIs were suggestive of increased risks, the 95% prediction intervals often included the null, reflecting the high heterogeneity of the estimates.

CONCLUSION

Given the suggested increased risks of cardiovascular outcomes in lymphoma survivor populations relative to the general population, tailored screening and prevention programmes may be warranted to offset the future burden of disease.

Long-term risk of congestive heart failure in younger breast cancer survivors: A nationwide study by the SMARTSHIP group

BACKGROUND

There is a controversy about late-onset congestive heart failure (CHF) among breast cancer survivors. This study investigated the incidence rate and risk factors of late-onset CHF more than 2 years after the breast cancer diagnosis.

METHODS

A nationwide, retrospective study was conducted with the National Health Information Database. With 1:3 age- and sex-matched noncancer controls, Cox proportional hazard regression models were used to analyze the incidence and risk factors of late CHF. The cumulative incidence rate of late CHF was evaluated with a Kaplan-Meier analysis and a log-rank test.

RESULTS

A total of 91,227 cases (286,480 person-years) and 273,681 controls (884,349 person-years) were evaluated between January 2007 and December 2013. The risks of late CHF were higher in cases than controls (hazard ratio [HR], 1.396; 95% confidence interval [CI], 1.268-1.538). Younger survivors (age ≤ 50 years) showed a higher risk of late CHF than their younger counterparts (HR, 2.903; 95% CI, 2.425-3.474). Although older age was a risk factor for late CHF, older survivors (age ≥ 66 years) showed no difference in the risk of late CHF in comparison with their counterparts (HR, 0.906; 95% CI, 0.757-1.084). Anthracyclines and taxanes were risk factors for late CHF, although trastuzumab, radiation, and endocrine therapy were not.

CONCLUSIONS

Young breast cancer survivors have a greater risk of late CHF than the young population without cancer. More attention should be paid to young breast cancer survivors who receive taxane- or anthracycline-based regimens over the long term.

Nicotinamide riboside promotes autolysosome clearance in preventing doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is widely used as a first-line chemotherapeutic drug for various malignancies. However, DOX causes severe cardiotoxicity, which limits its clinical uses. Oxidative stress is one of major contributors to DOX-induced cardiotoxicity. While autophagic flux serves as an important defense mechanism against oxidative stress in cardiomyocytes, recent studies have demonstrated that DOX induces the blockage of autophagic flux, which contributes to DOX cardiotoxicity. The present study investigated whether nicotinamide riboside (NR), a precursor of nicotinamide adenine dinucleotide (NAD)⁺, prevents DOX cardiotoxicity by improving autophagic flux. We report that administration of NR elevated NAD⁺ levels, and reduced cardiac injury and myocardial dysfunction in DOX-injected mice. These protective effects of NR were recapitulated in cultured cardiomyocytes upon DOX treatment. Mechanistically, NR prevented the blockage of autophagic flux, accumulation of autolysosomes, and oxidative stress in DOX-treated cardiomyocytes, the effects of which were associated with restoration of lysosomal acidification. Furthermore, inhibition of lysosomal acidification or SIRT1 abrogated these protective effects of NR during DOX-induced cardiotoxicity. Collectively, our study shows that NR enhances autolysosome clearance via the NAD⁺/SIRT1 signaling, thereby preventing DOX-triggered cardiotoxicity.

Targeting the COX/mPGES-1/PGE2 Pathway in Neuroblastoma

The importance of prostaglandin E₂ in cancer progression is well established, but research on its role in cancer has so far mostly been focused on epithelial cancer in adults while the knowledge about the contribution of prostaglandin E₂ to childhood malignancies is limited. Neuroblastoma, an extracranial solid tumor of the sympathetic nervous system, mainly affects young children. Patients with tumors classified as high-risk have poor survival despite receiving intensive treatment, illustrating a need for new treatments complimenting existing ones. The basis of neuroblastoma treatment e.g. chemotherapy and radiation therapy, target the proliferating genetically unstable tumor cells leading to treatment resistance and relapses. The tumor microenvironment is an avenue, still to a great extent, unexplored and lacking effective targeted therapies. Cancer-associated fibroblasts is the main source of prostaglandin E₂ in neuroblastoma contributing to angiogenesis, immunosuppression and tumor growth. Prostaglandin E₂ is formed from its precursor arachidonic acid in a two-step enzymatic reaction. Arachidonic acid is first converted by cyclooxygenases into prostaglandin H₂ and then further converted by microsomal prostaglandin E synthase-1 into prostaglandin E₂. We believe targeting of microsomal prostaglandin E synthase-1 in cancer-associated fibroblasts will be an effective future therapeutic strategy in fighting neuroblastoma.

Long-term risk of cardiovascular mortality in lymphoma survivors: A systematic review and meta-analysis

Cardiovascular disease has been identified as one of the late complications of cancer therapy. The purpose of this study was to quantify the long-term risk of cardiovascular mortality among lymphoma survivors relative to that of the general population. A systematic review and meta-analysis were conducted. Articles were identified in November 2016 by searching EMBASE, MEDLINE, and CINAHL databases. Observational studies were included if they assessed cardiovascular mortality in patients with lymphoma who survived for at least 5 years from time of diagnosis or if they had a median follow-up of 10 years. A pooled standardized mortality ratio (SMR) was estimated using a DerSimonian and Laird random-effects model. The Q and I2 statistics were used to assess heterogeneity. Funnel plots and Begg's and Egger's tests were used to evaluate publication bias. Of the 7450 articles screened, 27 studies were included in the systematic review representing 46 829 Hodgkin and 14 764 non-Hodgkin lymphoma survivors. The pooled number of deaths attributable to cardiovascular disease among Hodgkin and non-Hodgkin disease was estimated to be 7.31 (95% CI: 5.29-10.10; I2  = 95.4%) and 5.35 (95% CI: 2.55-11.24; I2  = 94.0%) times that of the general population, respectively. This association was greater among Hodgkin lymphoma survivors treated before the age of 21 (pooled SMR = 13.43; 95% CI: 9.22-19.57; I2  = 78.9%). There was a high degree of heterogeneity and a high risk of bias due to confounding in this body of literature. Lymphoma survivors have an increased risk of fatal cardiovascular events compared to the general population and should be targeted for cardiovascular screening and prevention campaigns.

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.

Aerobic exercise and cardiopulmonary fitness in childhood cancer survivors treated with a cardiotoxic agent: a meta-analysis

PURPOSE

The main purpose of this review was to synthesize evidence from existing childhood cancer survivor studies that report the effect of aerobic exercise on cardiopulmonary fitness (a marker of cardiovascular health), in survivors that were currently receiving or had been treated with a cardiotoxic agent.

METHODS

Studies were identified for this review by searching both electronic databases of peer-reviewed articles, as well as various sources of gray literature. Risk of bias was qualitatively assessed in these studies using the domains outlined in the Cochrane Handbook for Systematic Reviews of Interventions. Data was analyzed quantitatively using random-effects meta-analyses and subgroup analyses in RevMan Software.

RESULTS

Meta-analysis of pooled evidence from the nine included studies suggests that aerobic exercise has a statistically and clinically significant positive effect on cardiopulmonary fitness (effect estimate = 6.92%, p value = 0.02). Findings from subgroup analyses of clinical characteristics and exercise parameters were not significant.

CONCLUSIONS

The findings from this review, although not directly demonstrating a cardioprotective effect, are a preliminary step towards establishing the putative cardioprotective effect of aerobic exercise against the direct cardiotoxic impact of cancer treatments. The significant positive effect estimate in favor of aerobic exercise is a small but important advancement towards the standardization of aerobic exercise in childhood cancer survivors. Further studies are necessary.

Pharmacogenomics in pediatric acute lymphoblastic leukemia: promises and limitations

Despite the significant advances achieved in pediatric acute lymphocytic leukemia (ALL) treatment, adverse side effects of drugs remain a challenging issue. Numerous ALL pharmacogenomic studies have been conducted to elucidate the predisposing genetic factors for their development. Plausible pharmacogenomic data are available for the osteonecrosis associated with glucocorticoids, the neurotoxicity associated with vincristine and the cardiotoxicity related to anthracyclines. However, these data have not been fully translated into the clinic due to several limitations, most importantly the lack of reliable evidence. The most robust pharmacogenomics data are those for thiopurines and methotrexate use, with evidence-based preemptive testing recommendations for the former. Pharmacogenomics has a significant potential utility in pediatric ALL treatment regimens. In this review, gaps and limitations in this field are emphasized, which may provide a useful guide for future research design.

Cardiotoxicity from anthracycline and cardioprotection in paediatric cancer patients

Notwithstanding the steady progress in survival rates of children and adolescents suffering from cancer, the benefits associated with chemotherapy do not come without risks involving multiple organs and systems, including the cardiovascular apparatus. Anthracyclines-often administered in combination with radiation therapy and/or surgery-are the most used chemotherapeutic compounds in order to treat tumours and blood malignancies even in paediatric age. Being an important side-effect of anthracyclines, carduitoxicity may limit their efficacy during the treatment and induce long-term sequelae, observed even many years after therapy completion. The purpose of this review was to perform an overview about all the possible strategies to prevent and/or limit the anthracyclines adverse side-effects for the cardiovascular system in childhood cancer survivors.

Juvenile competitive triathlete after cardiotoxic anthracycline therapy for Acute Myeloid Leukemia

OBJECTIVE

The treatment of Acute Myeloid Leukemia (AML) leads to several functional limitations. Especially cardiac burden following cardiotoxic chemotherapy, which limits exercise and competitive sport in the long-term survivors.

SUBJECT AND METHODS

We report on a young female amateur triathlete born in 1997, who was diagnosed with AML at the age of fifteen. She had chemotherapy with a cumulative dose of about 1000 mg/m² anthracyclines and allogeneic stem cell transplantation which was successful, but she suffered from cardiotoxic systolic heart failure with a left ventricular ejection fraction (LVEF) <55 % and an impaired peak oxygen uptake of 23.2 ml/min/kg and 53 % of predicted, respectively. After medical examination and counselling with a sport scientist she started a tailored training of aerobic exercise. She was evaluated at regular intervals which resulted in increasing the training load and volume. Eventually her training hours was stepwise increased to 12 h training per week, which includes high intensity intervals.

RESULTS

Within almost 3 years, her exercise performance improved tremendously. Workload doubled from 2.1 W/kg to 4.2 W/kg, peak oxygen uptake increased from 23.2 ml/min/kg to 49.1 ml/min/kg and from 53 to 135 %, respectively. Moreover, she participated in several competitions. However, LVEF remains almost unchanged.

CONCLUSION

With the right training and under medical surveillance competitive exercise with an anthracycline-damaged heart is still achievable. Moreover, competitive training and exercise seems to be safe and feasible.

Cumulative burden of cardiovascular morbidity in paediatric, adolescent, and young adult survivors of Hodgkin's lymphoma: an analysis from the St Jude Lifetime Cohort Study

BACKGROUND

The magnitude of cardiovascular morbidity in paediatric, adolescent, and young adult survivors of Hodgkin's lymphoma is not known. Using medically ascertained data, we applied the cumulative burden metric to compare chronic cardiovascular health conditions in survivors of Hodgkin's lymphoma and general population controls.

METHODS

For this study, participant data were obtained from two ongoing cohort studies at St Jude Children's Research Hospital: the St Jude Lifetime Cohort Study (SJLIFE) and the St Jude Long-term Follow-up Study (SJLTFU). SJLIFE is a cohort study initiated on April 27, 2007, to enable longitudinal clinical evaluation of health outcomes of survivors of childhood cancer treated or followed at St Jude Children's Research Hospital, and SJLTFU is an administrative system-based study initiated in 2000 to collect outcome and late toxicity data for all patients treated at the hospital for childhood cancer. The patient cohort for our study was defined as patients treated at St Jude Children's Research Hospital who reached 18 years of age and were at least 10 years post-diagnosis of pathologically confirmed primary Hodgkin's lymphoma. Outcomes in the Hodgkin's lymphoma survivors were compared with a sample of SJLIFE community control participants, aged 18 years or older at the time of assessment, frequency-matched based on strata defined by 5-year age blocks within each sex, who were selected irrespective of previous medical history. All SJLIFE participants underwent assessment for 22 chronic cardiovascular health conditions. Direct assessments, combined with retrospective clinical reviews, were used to assign severity to conditions using a modified Common Terminology Criteria of Adverse Events (CTCAE) version 4.03 grading schema. Occurrences and CTCAE grades of the conditions for eligible non-SJLIFE participants were accounted for by multiple imputation. The mean cumulative count (treating death as a competing risk) was used to estimate cumulative burden.

FINDINGS

Of 670 survivors treated at St Jude Children's Research Hospital, who survived 10 years or longer and reached age 18 years, 348 were clinically assessed in the St Jude Lifetime Cohort Study (SJLIFE); 322 eligible participants did not participate in SJLIFE. Age and sex frequency-matched SJLIFE community controls (n=272) were used for comparison. At age 50 years, the cumulative incidence of survivors experiencing at least one grade 3-5 cardiovascular condition was 45·5% (95% CI 36·6-54·3), compared with 15·7% (7·0-24·4) in community controls. The survivor cohort at age 50 experienced a cumulative burden of 430·6 (95% CI 380·7-480·6) grade 1-5 and 100·8 (77·3-124·3) grade 3-5 cardiovascular conditions per 100 survivors; these numbers were appreciably higher than those in the control cohort (227·4 [192·7-267·5] grade 1-5 conditions and 17·0 [8·4-27·5] grade 3-5 conditions per 100 individuals). Myocardial infarction and structural heart defects were the major contributors to the excess grade 3-5 cumulative burden in survivors. High cardiac radiation dose (≥35 Gy) was associated with an increased proportion of grade 3-5 cardiovascular burden, whereas increased anthracyline dose was not.

INTERPRETATION

The true effect of cardiovascular morbidity in paediatric, adolescent, and young adult survivors of Hodgkin's lymphoma is reflected in the cumulative burden. Survivors aged 50 years will experience more than two times the number of chronic cardiovascular health conditions and nearly five times the number of more severe (grade 3-5) cardiovascular conditions compared with community controls and, on average, have one severe, life-threatening, or fatal cardiovascular condition. The cumulative burden metric provides a more comprehensive approach for assessing overall morbidity compared with currently used cumulative incidence based analytic methodologies, and will assist clinical researchers when designing future trials and refining general practice screening guidelines.

FUNDING

US National Cancer Institute, St Baldrick's Foundation, and American Lebanese Syrian Associated Charities.