Evaluation of traditional and novel measures of cardiac function to detect anthracycline-induced cardiotoxicity in survivors of childhood cancer

Assessment of Metabolic Syndrome and Kidney and Heart Function in Childhood Cancer Survivors

BACKGROUND

The survivors of childhood cancer suffer from a number of long-term side effects. These include atherosclerosis and cardiovascular diseases (CVDs) that develop earlier in adulthood than in the rest of the population. The aim of this study was to identify prognostic factors of developing atherosclerosis before the development of symptomatic CVD.

METHODS

A total of 141 children that were 7-18 years old were examined; there were 116 survivors of childhood malignancies (hematopoietic and lymphoproliferative malignancies-52; neuroblastoma-22; Wilms tumor-24; other solid tumors-18) and 25 healthy controls. Anthropometric measurements, blood pressure measurements, ultrasonography of the abdomen, echocardiography, and laboratory tests were performed.

RESULTS

There were no significant differences in gender distribution, time from the end of the treatment, weight, BMI, prevalence of central obesity, blood pressure and resistive index of the renal arteries, lipid profile, or glucose and fibrinogen levels. Patients with solid tumors had a significantly lower height and worse renal function. Patients with hematological malignancies significantly presented the lowest shortening fraction of the left ventricle. The salusin β levels were significantly higher in the control group than among the patients.

CONCLUSIONS

The type and severity of side effects are closely related to the type of neoplasm and the treatment that has been undergone. Careful observation and regular follow-up are necessary.

Natural history of myocardial deformation in children, adolescents, and young adults exposed to anthracyclines: Systematic review and meta-analysis

OBJECTIVE

Anthracyclines are widely used to treat solid and hematologic malignancies, but are known to cause cardiotoxicity. As more childhood cancer survivors reach adulthood due to improvements in oncologic treatments, they become susceptible to late and progressive anthracycline-induced cardiotoxicity. Nonetheless, diagnostic criteria for early detection of cardiac dysfunction are not well defined in children, adolescent, and young adults (CAYA, ages 1-40 years). We present a natural history of the changes in myocardial deformation in CAYA patients after anthracycline therapy.

METHODS

We performed a literature review search between 2001 and 2016 using PubMed with the following search terms: strain (or deformation), torsion (or twist), children (or adolescent or young adult), cardiotoxicity (or dysfunction), and anthracyclines (or doxorubicin). A total of 23 articles were reviewed. Fourteen articles were incorporated in the meta-analysis.

RESULTS

Strain abnormalities are observed at both short-term and long-term follow-up. Global longitudinal strain (GLS) abnormalities are common during or early after chemotherapy, whereas changes in global circumferential strain (GCS) are more significant and consistent on long-term follow-up. Although global radial strain and torsional parameters are also often abnormal late after chemotherapy, there are few studies evaluating these parameters.

CONCLUSION

There are significant abnormalities in GLS and GCS following anthracycline therapy acutely and late after treatment. The prognostic value of these strain abnormalities warrants further investigation.

Cardiotoxicity of anthracycline therapy: current perspectives

Anthracyclines, especially doxorubicin and daunorubicin, are the drugs of first choice in the treatment of patients with hematologic malignancies, soft-tissue sarcomas, and solid tumors. Unfortunately, the use of anthracyclines is limited by their dose-dependent and cumulative cardiotoxicity. The molecular mechanism responsible for anthracycline-induced cardiotoxicity remains poorly understood, although experimental and clinical studies have shown that oxidative stress plays the main role. Hence, antioxidant agents, especially dexrazoxane, and also other drug classes (statins, β-blockers) proved to have a beneficial effect in protecting against anthracycline-induced cardiotoxicity. According to previous clinical trials, the major high-risk factors for anthracycline-induced cardiotoxicity are age, body weight, female gender, radiotherapy, and other diseases such as Down syndrome, familial dilated cardiomyopathy, diabetes and hypertension. Consequently, further studies are needed to elucidate the molecular pathogenesis of anthracycline-induced cardiotoxicity and also to discover new cardioprotective agents against anthracycline-induced cardiotoxicity.

Echocardiographic Detection of Cardiac Dysfunction in Childhood Cancer Survivors: How Long Is Screening Required?

BACKGROUND

Childhood cancer survivors treated with anthracycline chemotherapy are at an increased risk of long-term cardiac toxicity, and guidelines recommend that exposed survivors undergo echocardiography every 1-5 years. However, it is unclear whether survivors should undergo echocardiographic screening indefinitely, or if a period of echocardiographic stability indicates that screening is no longer necessary. The objective of this study was to evaluate the outcomes of echocardiographic screening to aid in the refinement of existing guidelines.

METHODS

We retrospectively analyzed the results of echocardiographic screening in a cohort of adult survivors of childhood cancer treated with anthracyclines and/or cardiac radiation therapy. Interval regression analysis was performed to identify predictors of single-episode or sustained abnormal echocardiograms.

RESULTS

The cohort constituted 333 survivors, with median follow-up time of 15.8 years post-treatment (range: 5.0-47.9), and median age at treatment of 8 years (range: 1.5-18). Forty-nine survivors had an abnormal echocardiogram (14.7%), and 29 (8.7%) had reproducible abnormal findings. An ongoing continual increase in the incidence of sustained echocardiographic abnormality was seen among patients treated with >250 mg/m(2) doxorubicin at age <5 years, reaching 43% by 20 years of therapy. In contrast, no sustained abnormal echocardiographic findings arose after 10 years of therapy in survivors treated with <250 mg/m(2) at age ≥5 years.

CONCLUSIONS

Single-episode echocardiographic abnormalities are often not reproduced in subsequent evaluations. The duration of echocardiographic screening for childhood cancer survivors should be reassessed for patients who received lower doses of anthracycline after age 5.

Fetal outcome after prenatal exposure to chemotherapy and mechanisms of teratogenicity compared to alcohol and smoking

INTRODUCTION

The treatment of cancer during pregnancy is challenging because of the involvement of two individuals and the necessity of a multidisciplinary approach. An important concern is the potential impact of chemotherapy on the developing fetus.

AREAS COVERED

The authors review the available literature on neonatal and long-term outcome of children prenatally exposed to chemotherapy. Chemotherapy administered during first trimester of pregnancy results in increased congenital malformations (7.5 - 17% compared to 4.1 - 6.9% background risk), whereas normal rates are found during second or third trimester. Intrauterine growth restriction is seen in 7 - 21% (compared to 10%), but children develop normal weight and height on the long term. Children are born preterm in 67.1%, compared to 4% in general population. Normal intelligence, attention, memory and behavior are reported, although intelligence tends to decrease with prematurity. Global heart function remains normal, although small differences are seen in ejection fraction, fractional shortening and some diastolic parameters. No secondary cancers or fertility problems are encountered, but follow up periods are limited.

EXPERT OPINION

Most evidence is based on retrospective studies with small samples and limited follow up periods, methodology and lack of control groups. A large prospective case-control study with long-term follow up is needed in which confounding factors are well considered.