Risk Factors for Heart Failure Among Pan-European Childhood Cancer Survivors: A PanCareSurFup and ProCardio Cohort and Nested Case-Control Study

Influence of therapy exposures on specific late morbidities, prescription drug purchases, and mortality in aging male survivors of childhood cancer: A registry-based study

Childhood cancer treatments predispose to late health problems and premature death. Our aim was to use national registry data to study associations between cancer therapy exposures and late health outcomes in aging male childhood cancer survivors (CCS). The study comprised 200 male CCS (survival ≥5 years) treated with conventional cancer therapy at a single institution in 1964-2000 and 1000 matched population controls. Analyses involved registry-based data on prescription drug purchases, reimbursements for chronic conditions, hospital admissions, and deaths that occurred ≥5 years after the cancer diagnosis. Mean age of CCS was 45.4 years. Compared to population controls, CCS had a higher risk for hospital admissions due to cardiovascular diseases and late mortality, both of which increased after age 40 years. CCS also had a higher risk for purchases of antihypertensives and lipid-lowering drugs within the last year of the study. Heart radiation ≥10 Gy was associated with hospitalizations due to cardiovascular diseases (HR 4.14, 95%CI 1.81-9.48), purchases of antihypertensives (OR 3.05, 95%CI 1.32-7.36), and purchases of lipid-lowering drugs (OR 2.93, 95%CI 1.08-7.73). Testosterone deficiency developed typically during pediatric follow-up, and it was associated with testicular radiation ≥20 Gy (HR 41.2, 95%CI 15.4-110) but not with alkylating agents. Of patients treated with testicular radiation ≥20 Gy, 91% had purchased testosterone within the last year. Reassuringly, CCS had no excess risk for purchases of opioids, anxiolytics, antiepileptics, or antidepressants. These findings emphasize the need for risk-based follow-up. Middle-aged male CCS are at an increased risk of premature cardiovascular morbidity and excess mortality.

Late effects of the treatment of childhood cancer

Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies, with more than 80% of children with cancer who have access to contemporary treatment being cured. However, the therapies responsible for this survival can also produce adverse physical and psychological long-term outcomes, referred to as late effects, which appear months to years after the completion of cancer treatment. Research has shown that 60% to 90% of childhood cancer survivors (CCSs) develop one or more chronic health conditions, and 20% to 80% of survivors experience severe or life-threatening complications during adulthood. Therefore, understanding the late side effects of such treatments is important to improve the health and quality of life of the growing population of CCSs.

JCCG ALL-B12: Evaluation of Intensified Therapies With Vincristine/Dexamethasone Pulses and Asparaginase and Augmented High-Dose Methotrexate for Pediatric B-ALL

PURPOSE

The JCCG ALL-B12 clinical trial aimed to evaluate the effectiveness of unvalidated treatment phases for pediatric ALL and develop a safety-focused treatment framework.

PATIENTS AND METHODS

Patients age 1-19 years with newly diagnosed B-ALL were enrolled in this study. These patients were stratified into standard-risk (SR), intermediate-risk (IR), and high-risk (HR) groups. Randomized comparisons assessed the effectiveness of vincristine (VCR)/dexamethasone pulses in the SR group, evaluated the effects of L-asparaginase (ASP) intensification in the IR group, and compared standard consolidation including block-type treatment with experimental consolidation with high-dose methotrexate (HD-MTX) intensified with VCR and ASP in the HR group.

RESULTS

Of 1,936 patients enrolled, 1,804 were eligible for the experimental treatment. The overall 5-year event-free survival and overall survival rates were 85.2% (95% CI, 83.5 to 86.8) and 94.3% (95% CI, 93.1 to 95.3), respectively. The cumulative incidence of relapse and postremission nonrelapse mortality was 13.2% (95% CI, 11.6 to 14.8) and 0.6% (95% CI, 0.3 to 1.0), respectively. Random assignment in the SR group showed no significant benefit from pulse therapy. In the IR group, ASP intensification had limited effects. In the HR group, standard block therapy and HD-MTX yielded equivalent outcomes.

CONCLUSION

The ALL-B12 trial achieved favorable outcomes in a nationwide cohort by stratifying treatment on the basis of risk and balancing treatment intensity. This study not only demonstrated that existing standard of care can be further refined but also indicated that improvement in outcomes with intensified chemotherapy has reached a plateau.

Heart failure in patients with congenital heart disease after a cancer diagnosis

AIMS

Individuals with congenital heart disease (CHD) are at an increased risk for cancer. As cancer survival rates improve, the prevalence of late side effects, such as heart failure (HF), is becoming more evident. This study aims to evaluate the risk of developing HF following a cancer diagnosis in patients with CHD, compared with those without CHD and with CHD patients who do not have cancer.

METHODS

CHD patients (n = 69 799) and randomly selected non-CHD controls (n = 650 406), born in Sweden between 1952 and 2017, were identified from the Swedish National Health Registers and Total Population Register (excluding those with syndromes and transplant recipients). CHD patients who developed cancer (n = 1309) were propensity score-matched with non-CHD patients who developed cancer (n = 9425), resulting in a cohort of 1232 CHD patients with cancer and 2602 non-CHD controls with cancer (after exclusion of individuals with HF prior to cancer diagnosis). In a separate analysis, CHD patients with cancer were propensity score-matched with CHD patients without cancer (n = 68 490). A total of 1233 CHD patients with cancer and 2257 CHD patients without cancer were included in the study.

RESULTS

Among CHD patients with cancer, 73 (5.9%) developed HF during a mean follow-up time of 8.5 ± 8.7. Comparatively, in the propensity-matched control population, 29 (1.1%) non-CHD cancer patients (mean follow-up time of 7.3 ± 7.5) and 101 (4.5%) CHD patients without cancer (mean follow-up time of 9.9 ± 9.2) developed HF. CHD patients exhibited a significantly higher risk of HF post-cancer diagnosis compared with the non-CHD control group [hazard ratio (HR) 4.39, 95% confidence interval (CI) 2.83-6.81], after adjusting for age at cancer diagnosis and comorbidities. In the analysis between CHD patients with cancer and those without cancer, the results indicated a significantly higher risk of developing HF in CHD patients with cancer (HR 1.53, 95% CI 1.13-2.07).

CONCLUSIONS

CHD patients face a more than four-fold increased risk of developing HF after a cancer diagnosis compared with cancer patients without CHD. Among CHD patients, the risk of HF is only modestly higher for those with cancer than for those without cancer. This suggests that the increased HF risk in CHD patients with cancer, relative to non-CHD cancer patients, may be more attributable to CHD itself than to cancer treatment-related side effects.

Prevention of cardiotoxicity in childhood cancer survivors: In physical exercise, we trust

In recent years, the mean survival rate of children after a cancer diagnosis has significantly improved. At the same time, a growing interest in short and long-term cardiovascular (CV) complications of cancer therapy, as well as long-term CV risk in childhood cancer survivors (CCS) developed, along with proposals of protocols for the diagnosis, management, and prevention of cancer therapy-related CV toxicity (CTR-CVT) in this population. Many clinical and individual risk factors for CTR-CVT have been identified, and a non-negligible prevalence of traditional CV risk factors has been described in this population, potentially associated with a further worsening in both CTR-CVT and long-term CV risk. Physical exercise (PE) represents a promising, free-of-cost and free-of-complications, helpful therapy for primary and secondary prevention of CTR-CVT in CCS. The present narrative review aims to summarize the most critical evidence available about CTR-CVT in CCS, focusing on the role of PE in this clinical scenario.

Morbidity and mortality among children, adolescents, and young adults with cancer over six decades: a Swedish population-based cohort study (the Rebuc study)

Background

Despite progress in managing cancer in children, adolescents, and young adults (CAYAs), persistent complications may impact their quality of life. This study covers the morbidity and mortality, among CAYAs, with the aim to investigate the influence of socioeconomic factors on outcomes.

Methods

This retrospective matched cohort study included the entire Swedish population of individuals under 25 with cancer 1958-2021. The population was identified from the Cancer Register, and controls were paired 1:5 based on age, sex, and residence. Multiple registers provided data on morbidity, mortality, and demographics.

Findings

This survey covering 63 years, identified 65,173 CAYAs and matched controls, a total of 378,108 individuals (74% females). CAYAs exhibited a 3.04-times higher risk for subsequent cancer (Odds ratio (OR) 95% confidence interval (CI) 2.92-3.17, p < 0.0001), a 1.23-times higher risk for cardiovascular disease (OR 95% CI 1.20-1.26, p < 0.0001), and a 1.41-times higher risk for external affliction (OR 95% CI 1.34-1.49, p < 0.0001). CAYAs had a higher mortality hazard, and after adjusting for socioeconomic factors, males, individuals born outside Europe, and those with greater sick-leave had a higher association with mortality, while education and marriage showed a beneficial association.

Interpretation

The Rebuc study, showed an increased risk for serious complications among young cancer patients in Sweden. Patient-specific variables, demographics, and socioeconomic factors influenced mortality. These results underscore the impact of cancer on the health and lifespan of young individuals and the necessity for further research to address socioeconomic disparities in cancer care.

Funding

Grants from the Medical Research Council of Southeast Sweden (FORSS), ALF Grants, Region Ostergotland, and The Swedish Childhood Cancer Fund.

Reporting Standards for Complication Studies of Radiation Therapy for Pediatric Cancer: Lessons From PENTEC

The major aim of Pediatric Normal Tissue Effects in the Clinic (PENTEC) was to synthesize quantitative published dose/-volume/toxicity data in pediatric radiation therapy. Such systematic reviews are often challenging because of the lack of standardization and difficulty of reporting outcomes, clinical factors, and treatment details in journal articles. This has clinical consequences: optimization of treatment plans must balance between the risks of toxicity and local failure; counseling patients and their parents requires knowledge of the excess risks encountered after a specific treatment. Studies addressing outcomes after pediatric radiation therapy are particularly challenging because: (a) survivors may live for decades after treatment, and the latency time to toxicity can be very long; (b) children's maturation can be affected by radiation, depending on the developmental status of the organs involved at time of treatment; and (c) treatment regimens frequently involve chemotherapies, possibly modifying and adding to the toxicity of radiation. Here we discuss: basic reporting strategies to account for the actuarial nature of the complications; the reporting of modeling of abnormal development; and the need for standardized, comprehensively reported data sets and multivariate models (ie, accounting for the simultaneous effects of radiation dose, age, developmental status at time of treatment, and chemotherapy dose). We encourage the use of tools that facilitate comprehensive reporting, for example, electronic supplements for journal articles. Finally, we stress the need for clinicians to be able to trust artificial intelligence models of outcome of radiation therapy, which requires transparency, rigor, reproducibility, and comprehensive reporting. Adopting the reporting methods discussed here and in the individual PENTEC articles will increase the clinical and scientific usefulness of individual reports and associated pooled analyses.

Aging and cancer

Aging and cancer exhibit apparent links that we will examine in this review. The null hypothesis that aging and cancer coincide because both are driven by time, irrespective of the precise causes, can be confronted with the idea that aging and cancer share common mechanistic grounds that are referred to as 'hallmarks'. Indeed, several hallmarks of aging also contribute to carcinogenesis and tumor progression, but some of the molecular and cellular characteristics of aging may also reduce the probability of developing lethal cancer, perhaps explaining why very old age (> 90 years) is accompanied by a reduced incidence of neoplastic diseases. We will also discuss the possibility that the aging process itself causes cancer, meaning that the time-dependent degradation of cellular and supracellular functions that accompanies aging produces cancer as a byproduct or 'age-associated disease'. Conversely, cancer and its treatment may erode health and drive the aging process, as this has dramatically been documented for cancer survivors diagnosed during childhood, adolescence, and young adulthood. We conclude that aging and cancer are connected by common superior causes including endogenous and lifestyle factors, as well as by a bidirectional crosstalk, that together render old age not only a risk factor of cancer but also an important parameter that must be considered for therapeutic decisions.

Validation of self-reported cardiovascular problems in childhood cancer survivors by contacting general practitioners: feasibility and results

BACKGROUND

Epidemiological studies often rely on self-reported health problems and validation greatly improves study quality. In a study of late effects after childhood cancer, we validated self-reported cardiovascular problems by contacting general practitioners (GPs). This paper describes: (a) the feasibility of this approach; and (b) the agreement between survivor-reports and reports from their GP.

METHODS

The Swiss Childhood Cancer Survivor Study (SCCSS) contacts all childhood cancer survivors registered in the Swiss Childhood Cancer Registry since 1976 who survived at least 5 years from cancer diagnosis. We validated answers of all survivors who reported a cardiovascular problem in the questionnaire. Reported cardiovascular problems were hypertension, arrhythmia, congestive heart failure, myocardial infarction, angina pectoris, stroke, thrombosis, and valvular problems. In the questionnaire, we further asked survivors to provide a valid address of their GP and a consent for contact. We sent case-report forms to survivors' GPs and requested information on cardiovascular diagnoses of their patients. To determine agreement between information reported by survivors and GPs, we calculated Cohen's kappa (κ) coefficients for each category of cardiovascular problems.

RESULTS

We used questionnaires from 2172 respondents of the SCCSS. Of 290 survivors (13% of 2172) who reported cardiovascular problems, 166 gave consent to contact their GP and provided a valid address. Of those, 135 GPs (81%) replied, and 128 returned the completed case-report form. Survivor-reports were confirmed by 54/128 GPs (42%). Of the 54 GPs, 36 (28% of 128) confirmed the problems as reported by the survivors; 11 (9% of 128) confirmed the reported problem(s) and gave additional information on more cardiovascular outcomes; and seven GPs (5% of 128) confirmed some, but not all cardiovascular problems. Agreement between GPs and survivors was good for stroke (κ = 0.79), moderate for hypertension (κ = 0.51), arrhythmias (κ = 0.41), valvular problems (κ = 0.41) and thrombosis (κ = 0.56), and poor for coronary heart disease (κ = 0.15) and heart failure (κ = 0.32).

CONCLUSIONS

Despite excellent GP compliance, it was found unfeasible to validate self-reported cardiovascular problems via GPs because they do not serve as gatekeepers in the Swiss health care system. It is thus necessary to develop other validation methods to improve the quality of patient-reported outcomes.

Cardiac electrical abnormalities in childhood acute lymphoblastic leukemia survivors: a systematic review

PURPOSE

The aim was to provide evidence about the prevalence, incidence, and risk factors of cardiac electrical abnormalities in childhood acute lymphoblastic leukemia (ALL) survivors.

METHODS

We included all original studies reporting the incidence and/or prevalence of cardiac electrical abnormalities and/or risk factors associated with cardiac electrical abnormalities in childhood ALL survivors (< 21 years old at the time of their initial cancer diagnosis) who were post-treatment. Searches of the databases PubMed, Ovid MEDLINE(R) and Epub Ahead of Print, In-Process, In-Data-Review & Other Non-Indexed Citations, Daily and Versions(R), Ovid All EBM Reviews, Ovid Embase, and ISI Web of Science were completed in May 2023. The risk of bias was assessed using the standard JBI critical appraisal checklists.

RESULTS

The 11 studies included in this review (N = 1,264 participants) evaluated various parameters, including different cardiac electrical abnormalities. Five studies reported heart rate abnormalities (0-68%), six reported repolarization disorders (0-30%), two reported depolarization disorders (0-1%), seven reported rhythm disturbances or abnormalities (0-100%), four reported conduction disorders (0-10%), and three reported unclassified abnormalities (1-38%). No risk factors were reported.

CONCLUSIONS

Electrical heart problems have been observed in childhood ALL survivors after completion of treatment. Large prospective studies in childhood ALL survivors, clear definitions of cardiac electrical abnormalities, and comparison with a control group are warranted.

IMPLICATIONS FOR CANCER SURVIVORS

Cardiac electrical abnormalities induced by chemotherapy-related cardiotoxicity in the growing population of childhood ALL survivors need to be better characterized to ensure better long-term follow-up and improve overall survival rate.

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.

Cardiac Substructure Radiation Dose and Risk of Late Cardiac Disease in Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study

PURPOSE

Radiation-associated cardiac disease is a major cause of morbidity/mortality among childhood cancer survivors. Radiation dose-response relationships for cardiac substructures and cardiac diseases remain unestablished.

METHODS

Using the 25,481 5-year survivors of childhood cancer treated from 1970 to 1999 in the Childhood Cancer Survivor Study, we evaluated coronary artery disease (CAD), heart failure (HF), valvular disease (VD), and arrhythmia. We reconstructed radiation doses for each survivor to the coronary arteries, chambers, valves, and whole heart. Excess relative rate (ERR) models and piecewise exponential models evaluated dose-response relationships.

RESULTS

The cumulative incidence 35 years from diagnosis was 3.9% (95% CI, 3.4 to 4.3) for CAD, 3.8% (95% CI, 3.4 to 4.2) for HF, 1.2% (95% CI, 1.0 to 1.5) for VD, and 1.4% (95% CI, 1.1 to 1.6) for arrhythmia. A total of 12,288 survivors (48.2%) were exposed to radiotherapy. Quadratic ERR models improved fit compared with linear ERR models for the dose-response relationship between mean whole heart and CAD, HF, and arrhythmia, suggesting a potential threshold dose; however, such departure from linearity was not observed for most cardiac substructure end point dose-response relationships. Mean doses of 5-9.9 Gy to the whole heart did not increase the risk of any cardiac diseases. Mean doses of 5-9.9 Gy to the right coronary artery (rate ratio [RR], 2.6 [95% CI, 1.6 to 4.1]) and left ventricle (RR, 2.2 [95% CI, 1.3 to 3.7]) increased risk of CAD, and to the tricuspid valve (RR, 5.5 [95% CI, 2.0 to 15.1]) and right ventricle (RR, 8.4 [95% CI, 3.7 to 19.0]) increased risk of VD.

CONCLUSION

Among children with cancer, there may be no threshold dose below which radiation to the cardiac substructures does not increase the risk of cardiac diseases. This emphasizes their importance in modern treatment planning.

The risk of valvular heart disease in the French Childhood Cancer Survivors' Study: Contribution of dose-volume histogram parameters

BACKGROUND AND PURPOSE

Valvular Heart Disease (VHD) is a known complication of childhood cancer after radiotherapy treatment. However, the dose-volume-effect relationships have not been fully explored.

MATERIALS AND METHODS

We obtained individual heart Dose Volume Histograms (DVH) for survivors of the French Childhood Cancer Survivors Study (FCCSS) who had received radiotherapy. We calculated the Mean Dose to the Heart (MHD) in Gy, as well as the heart DVH parameters (V_{d Gy}, which represents the percentage of heart volume receiving at least d Gy), fixing the thresholds to 0.1 Gy, 5 Gy, 20 Gy, and 40 Gy. We analyzed them furtherly in the subpopulation of the cohort that was treated with a dose lower than 5 Gy (V_0.1Gy|_V5Gy=0%), 20 Gy (V_5Gy|_V20Gy=0%), and 40 Gy (V_20Gy|_V40Gy=0%), respectively. We investigated their role in the occurrence of a VHD in this population-based observational cohort study using the Cox proportional hazard model, adjusting for age at cancer diagnosis and chemotherapy exposure.

RESULTS

Median follow-up was 30.6 years. Eighty-one patients out of the 7462 (1 %) with complete data experienced a severe VHD (grade ≥ 3). The risk of VHD increased along with the MHD, and it was associated with high doses to the heart (V_40Gy < 50 %, hazard ratio (HR) = 7.96, 95 % CI: 4.26-14.88 and V_20Gy|_V40Gy=0% >50 %, HR = 5.03, 95 % CI: [2.35-10.76]). Doses 5-20 Gy to more than 50 % (V_5Gy|_V20Gy=0% >50 %) of the heart induced a marginally non-significant estimated risk. We also observed a remarkable risk increase with attained age.

CONCLUSIONS

Our results provide new insight into the VHD risk that may impact current treatments and long-term follow-up of childhood cancer survivors.