Is Carotid Stiffness a Possible Surrogate for Stroke in Long-term Survivors of Childhood Cancer after Neck Radiotherapy?

Long-Term Adverse Effects of Neck Radiotherapy in Childhood on the Carotid Arteries in Survivors of Hodgkin Lymphoma

INTRODUCTION

Survivors of Hodgkin lymphoma are recognized to have an increased risk of stroke and carotid artery disease owing to neck irradiation (RT). However, it remains unclear whether the vascular modifications induced by the treatment of Hodgkin lymphoma during childhood persist over the long term.

METHODS

Our matched study involved 79 survivors of Hodgkin lymphoma in childhood who received neck RT and 57 healthy controls. Parameters of arterial stiffness (AS), intima-media thickness (IMT), and flow-mediated dilation (FMD) of carotid arteries were assessed using ultrasound.

RESULTS

Our patient cohort demonstrated a significant increase in AS compared to controls (p < 0.05), though no such disparity was observed for FMD (p = 0.111). Neck RT intensified AS (B = 0.037, p = 0.000), while anthracyclines attenuated it (B = -0.803, p = 0.000). Multivariate analysis revealed a positive correlation between neck RT (p < 0.001) and AS. However, we found no significant association between neck RT and FMD (p = 0.277). We identified a substantial positive correlation between the dose of neck RT and AS.

CONCLUSIONS

Vascular changes in survivors of childhood Hodgkin lymphoma after neck RT seem to be long-term. Therefore, these patients may have an increased risk of stroke. We suggest refinement of international guidelines according to our results.

Cardiovascular Risk in Childhood Cancer Survivors

Cancer is a prominent cause of death worldwide in the pediatric population. Since childhood cancer is not possible to prevent, it is essential to focus on a prompt and correct diagnosis followed by effective, evidence-based therapy with individualized supportive care. Given the enhancement of childhood cancer management over the past decades, survival rate has significantly improved, thus leading to the progression of several late effects, including metabolic derangements. These metabolic imbalances are associated with the underlying disease and the cancer treatments. As a result, the metabolic state may contribute to a high risk of cardiovascular morbidity and premature mortality among childhood cancer survivors. This review aims to summarize the potential pathophysiological mechanisms linked to the risk of diabetes and metabolic syndrome and screening recommendations. Further investigations are needed to clarify the underlying mechanisms of such metabolic abnormalities and to improve long-term cardiometabolic survival among these patients.

The Relationship Between Cancer and Functional and Structural Markers of Subclinical Atherosclerosis: A Systematic Review and Meta-Analysis

Objectives

The relationship between cancer and subclinical atherosclerosis has always been the focus of people's attention. We conducted a systematic review and meta-analysis by evaluating the effects of cancer on functional and structural markers of subclinical atherosclerosis:intima-media thickness (IMT), pulse wave velocity (PWV), and flow-mediated vasodilation (FMD).

Methods

A comprehensive and systematic literature search was conducted on the internet. Sensitivity analysis, publication bias, standard mean difference (SMD), corresponding 95% confidence interval (95% CI), and subgroup analysis were performed for all relevant research indicators in the retrieved literature.

Results

Forty-six studies were included, including 3,729 cancer patients and 2,404 healthy controls. Cancer patients had significantly thicker IMT [SMD (95%CI) = 0.290 (0.069 to 0.511), P = 0.010] and higher PWV [SMD (95%CI) = 0.392 (0.136 to 0.647), P = 0.003] compared with healthy controls. There was no significant difference in FMD [SMD (95% CI) = −0.192 (−0.527 to 0.144), P > 0.05). After subgrouping by age, male proportion, and treatment, the analysis results of IMT ≥ 50 years old, PWV and FMD < 50 years old, male proportion ≥50%, chemotherapy group, IMT and PWV radiotherapy group, and PWV endocrine therapy group were statistically significant (P < 0.05). There were no significant differences in other subgroup analyses, overall sensitivity analysis, and publication bias (p < 0.05).

Conclusions

Cancer may promote subclinical atherosclerosis, and change the functional and structural markers of subclinical atherosclerosis such as IMT and PWV. Early intervention and prevention should be pursued.

Cardiovascular Function and Exercise Capacity in Childhood Cancer Survivors

Introduction: Childhood cancer survivors (CCS) might be at high risk of additional chronic diseases due to cardiotoxic side effects. The aim of this study was to analyze long-term side effects of cancer therapy on vascular structure/function, cardiac biomarkers and on physical activity. Methods: In total, 68 asymptomatic patients aged 16–30 years with childhood cancer (diagnosed 10.6 ± 3.9 years ago) were examined from 2015–2020. (Central) blood pressure and pulse wave velocity were registered via the oscillometric method, while carotid intima-media thickness (cIMT) was measured non-invasively by ultrasound. cIMT values of patients were compared to healthy controls (n = 68; aged 22.3 ± 3.5 years). Patients’ exercise capacity was recorded. The plasma N-terminal pro-brain natriuretic protein (NTproBNP) and troponin levels were measured as cardiac biomarkers. CCS were categorized in groups with low, moderate and high anthracyclines. Results: No differences were found in cIMT between patients and controls as well as between patients with various anthracycline dosage. Patients with high dose anthracyclines showed a significant lower performance versus patients with moderate dose anthracyclines (84.4% of predicted VO₂peak; p = 0.017). A total of 11.6% of CCS had abnormal NTproBNP values which correlated with received anthracycline dosage (p = 0.024; r = 0.343). Conclusion: NTproBNP levels and exercise capacity might be early markers for cardiovascular dysfunction in CCS and should be included in a follow-up protocol, while cIMT and troponin seem not to be adequate parameters.

Arterial stiffness as an ultrasound biomarker of radiation-induced carotid artery disease

Background: Radiation-induced carotid artery disease (RICAD) is an important issue in head and neck cancer (HNC) survivors after radiotherapy (RT). The risk of cerebrovascular disease in these patients is doubled. The aim of this study was to assess the effect of RT on carotid artery stiffness in HNC patients. Patients and methods: Conventional arterial stiffness parameters were measured in a total of 50 HNC survivors treated with RT for at least 5 years and compared to 50 unirradiated HNC patients. Elastic modulus (Ep) and Beta stiffness index (β) were measured in proximal, mid and distal common carotid artery (CCA). Results: The mean age of the subjects was 68±9 years (range: 44-84) in the irradiated group and 67±10 years (range: 45-85) in the control group. The RT group was treated with a mean radiation exposure of 60.3±6.7 Gy (range: 44-72) in the neck. Carotid stiffness parameters showed significant group differences: Ep in the RT group was 2.329±1.222 vs 1.742±828 in the non-RT group (p=0.006) and β index in the RT group was 23±11 vs 15±8 in the non-RT group (p<0.001). Radiation-induced carotid stiffness was quantified and cervical exposure to RT increased Ep in 575 kPa (p=0.014) and β in 7 units (p<0.003). Conclusions: Ep and β index could be suitable ultrasound biomarkers of radiation-induced atherosclerosis in HNC survivors. Further prospective studies are needed to feature RICD in this setting.

Characterization of Cardiac, Vascular, and Metabolic Changes in Young Childhood Cancer Survivors

Background: Childhood cancer survivors (CCS) are at an increased risk for cardiovascular diseases (CVD). It was the primary aim of this study to determine different measures of cardiac, carotid, lipid, and apolipoprotein status in young adult CCS and in healthy controls. Methods: Cardiac and common carotid artery (CCA) structure and function were measured by ultrasonography. Lipids and apolipoproteins were measured in the blood. Peripheral arterial endothelial vasomotor function was assessed by measuring digital reactive hyperemia index (PAT-RHI) using the Endo-PAT 2000. Results: Fifty-three CCS (20-30 years, 35 men) and 53 sex-matched controls were studied. The CCS cohort was divided by the median dose of anthracyclines into a low anthracycline dose (LAD) group (50-197 mg/m², n = 26) and a high anthracycline dose (HAD) group (200-486 mg/m², n = 27). Carotid distensibility index (DI) and endothelial function determined by PAT-RHI were both lower in the CCS groups compared with controls (p < 0.05 and p = 0.02). There was no difference in carotid intima media thickness. Atherogenic apolipoprotein-B (Apo-B) and the ratio between Apo-B and Apoliprotein-A1 (Apo-A1) were higher in the HAD group compared with controls (p < 0.01). Apo-B/Apo-A1-ratio was over reference limit in 29.6% of the HAD group, in 15.4% of LAD group, and in 7.5% of controls (p = 0.03). Measured lipid markers (low density lipoprotein and total cholesterol and triglycerides) were higher in both CCS groups compared with controls (p < 0.05). Systolic and diastolic function were measurably decreased in the HAD group, as evidenced by lower EF (p < 0.001) and lower é-wave (p < 0.005) compared with controls. CCA DI correlated with Apo-B/Apo-A1-ratio and Apo-A1. Follow-up time after treatment correlated with decreased left ventricular ejection fraction (p = 0.001). Conclusion: Young asymptomatic CCS exhibit cardiac, vascular, lipid, and apolipoprotein changes that could account for increased risk for CVD later in life. These findings emphasize the importance of cardiometabolic monitoring even in young CCS.