Screening for coronary artery disease after mediastinal irradiation in Hodgkin lymphoma survivors: phase II study of indication and acceptance†

Translating Between Radiation Dose and Late Toxicity for Lymphoma Survivors: Implications on Toxicity Counseling and Survivorship

Radiation therapy (RT) is an important modality in the modern management of lymphoma. RT has long been recognized as a cause of late toxicity in lymphoma survivors, including serious morbidity and increased mortality from second cancers and cardiovascular disease. Many studies have quantified the relationships between radiation dose to normal tissues and the risk of late toxicities. These relationships offer the opportunity to estimate future risks for patients on an individual basis. This knowledge has the potential to effect up-front management decisions regarding the use of RT, optimize radiotherapy planning for treatment, guide the evolution of future RT technologies and identify past and future patients whose risk of late toxicity is sufficient to warrant specific screening and surveillance strategies. Despite these potential applications the challenges around translating between radiation dose and accurate predictions of late toxicities are many and substantial. This article summarizes the current state of knowledge, the inherent challenges and possible directions for future research to address this area.

Cardio-oncology and radiation oncology: How collaboration between cardiologists and oncologists can be realised in radiation oncology

Increased survivorship, improvements in cancer treatments, and the potential for cardiac side effects from cancer treatments have resulted in increased collaboration between oncologists and cardiologists and the development of cardio-oncology clinics. This collaboration is important given its role in ensuring greater patient satisfaction, aiding teams of clinicians in making complex treatment decision, and ensuring cardiac complications are diagnosed at an early stage. The particularities of implementing this collaboration in the field of radiation oncology and how this setting is different from other areas of cardio-oncology have not been well detailed in the literature. This paper will discuss what is currently understood about the need for and role of cardio-oncology and what a cardio-oncology services involves, with a particular emphasis on patient and clinician needs in the field of radiation oncology. The literature and recent guidelines do advocate for a detailed baseline assessment of cancer patients undergoing radiotherapy, especially patients with treatment or patient risk factors that increase their risk of cancer-therapy related cardiotoxicity. Advancements in cardiac imaging techniques will be discussed as these may help to diagnose cardiac side effects of certain cancer treatments, including radiotherapy, at an early stage. A multi-disciplinary and collaborative approach is well received by patients and such an approach, guided by the aim of maintaining a patient's cancer treatment wherever possible, should be the cornerstone of cardio-oncology clinics regardless of the patient's treatment regime.

Relation between Coronary Artery Calcium Score and Cardiovascular Events in Hodgkin Lymphoma Survivors: A Cross-Sectional Matched Cohort Study

BACKGROUND

Thoracic radiotherapy is one of the corner stones of HL treatment, but it is associated with increased risk of cardiovascular events. As HL is often diagnosed at a young age, long-term follow-up including screening for coronary artery disease (CAD) is recommended.

OBJECTIVES

This study aims to evaluate the presence of coronary artery calcium score (CACS) in relation to cardiovascular events in HL patients treated with thoracic radiotherapy compared to a non-cancer control group.

METHODS

Consecutive HL patients who underwent evaluation for asymptomatic CAD with coronary computed tomography angiography > 10 years after thoracic irradiation were included. The study population consisted of 97 HL patients matched to 97 non-cancer patients on gender, age, cardiovascular risk factors, and statin use.

RESULTS

Mean age during CT scan in the HL population was 45.5 ± 9.9 and in the non-cancer population 45.5 ± 10.3 years. CACS was elevated (defined as >0) in 49 (50.5%) HL patients and 30 (30.9%) control patients. HL survivors had an odds ratio of 2.28 [95% CI: 1.22-4.28] for having a CACS > 0 compared to the matched population (p = 0.006). Prevalence of CACS > 90th percentile differed significantly: 17.1% in HL survivors vs. 4.6% in the matched population (p = 0.009). Non-obstructive coronary artery stenosis was more prevalent in the HL population than in the control population (45.7% vs. 28.4%, respectively, p = 0.01). During follow-up of 8.5 [5.3; 9.9] years, nine HL patients experienced an event including two patients with a CACS of zero. No events occurred in the control population.

CONCLUSION

In a matched study population, HL survivors have a higher prevalence of a CACS > 0 and an increased risk of cardiovascular events after thoracic irradiation compared to a matched non-cancer control group.

Cardiac surgery for radiation associated heart disease in Hodgkin lymphoma patients

Much of the modern focus of Hodgkin's Lymphoma (HL) treatment involves the prevention of secondary organ injury. Despite rationalisations of radiotherapy fields, many patients still develop late radiation-related cardiotoxicity that is severe and requires interventional management. No guidelines exist to direct management of these complex patients who often present with multiple concurrent cardiac pathologies. Despite possessing a greater mortality risk than in the general population, cardiac surgery has an important role in treating radiation-associated heart disease. This review summarises the body of literature surrounding cardiac surgery in HL survivors post-radiotherapy, highlighting the benefits and risks unique to this cohort. The pathophysiology and presentation of radiation-associated heart disease is also explored in relation to HL patients.

Exploring the Cardiotoxicity Spectrum of Anti-Cancer Treatments: Definition, Classification, and Diagnostic Pathways

Early detection and treatment of cancer have led to a noticeable reduction in both mortality and morbidity. However, chemotherapy and radiotherapy could exert cardiovascular (CV) side effects, impacting survival and quality of life, independent of the oncologic prognosis. In this regard, a high clinical index of suspicion is required by the multidisciplinary care team in order to trigger specific laboratory tests (namely natriuretic peptides and high-sensitivity cardiac troponin) and appropriate imaging techniques (transthoracic echocardiography along with cardiac magnetic resonance, cardiac computed tomography, and nuclear testing (if clinically indicated)), leading to timely diagnosis. In the near future, we do expect a more tailored approach to patient care within the respective community along with the widespread implementation of digital health tools.

Cardiac computed tomographic imaging in cardio-oncology: An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT). Endorsed by the International Cardio-Oncology Society (ICOS)

Cardio-Oncology is a rapidly growing sub-specialty of medicine, however, there is very limited guidance on the use of cardiac CT (CCT) in the care of Cardio-Oncology patients. In order to fill in the existing gaps, this Expert Consensus statement comprised of a multidisciplinary collaboration of experts in Cardiology, Radiology, Cardiovascular Multimodality Imaging, Cardio-Oncology, Oncology and Radiation Oncology aims to summarize current evidence for CCT applications in Cardio-Oncology and provide practice recommendations for clinicians.

The cardiac toxicity of radiotherapy - a review of characteristics, mechanisms, diagnosis, and prevention

PURPOSE

Radiation-induced heart disease (RIHD) is one of the most serious complications of radiotherapy. The purpose of this paper is to review recent researches about cardiac toxicity of radiotherapy in clinical characteristics, mechanisms, diagnosis, and prevention.

CONCLUSIONS

Powered by the rapid development of medicine, the overall survival (OS) of cancer has been improved significantly. Surgery, chemotherapy, and radiotherapy (RT) are three critical ways in the comprehensive treatments of cancer. There is a consensus that early diagnosis and interventions for the prevention of RIHD are crucial. This review concludes recent clinical and experimental studies on RIHD. RIHD, a heterogeneous and serious disease, is a spectrum of heart disease including myocardial disease, pericarditis, coronary artery disease, valvular heart disease, and conduction system dysfunction. Mean heart dose, biomarkers, and detecting techniques are important components in detecting heart injury. Improvements in radiotherapy regimens remain the primary goal of prevention. Further investigation is needed beyond the observation period of most of these studies.

Radiation-Induced Vascular Disease-A State-of-the-Art Review

Since the 1990s, there has been a steady increase in the number of cancer survivors to an estimated 17 million in 2019 in the US alone. Radiation therapy today is applied to a variety of malignancies and over 50% of cancer patients. The effects of ionizing radiation on cardiac structure and function, so-called radiation-induced heart disease (RIHD), have been extensively studied. We review the available published data on the mechanisms and manifestations of RIHD, with a focus on vascular disease, as well as proposed strategies for its prevention, screening, diagnosis, and management.

Contemporary Understandings of Cardiovascular Disease After Cancer Radiotherapy: a Focus on Ischemic Heart Disease

PURPOSE OF REVIEW

Radiation-induced cardiovascular disease, including coronary artery disease, is a well-known sequela of radiation therapy and represents a significant source of morbidity and mortality for cancer survivors. This review examines current literature and guidelines to care for this growing population of cancer survivors.

RECENT FINDINGS

The development of radiation-induced ischemic heart disease following radiation can lead even to early cardiotoxicities, inclusive of coronary artery disease, which limit cancer treatment outcomes. These coronary lesions tend to be diffuse, complex, and proximal. Early detection with multimodality imaging and targeted intervention is required to minimize these risks. Early awareness, detection, and management of radiation-induced cardiovascular disease are paramount as cancer survivorship continues to grow.

Reducing Heart Dose with Protons and Cardiac Substructure Sparing for Mediastinal Lymphoma Treatment

Purpose

Electrocardiogram-gated computed tomography with coronary angiography can be used for cardiac substructure sparing (CSS) optimization, which identifies and improves avoidance of cardiac substructures when treating with intensity modulated radiotherapy (IMRT). We investigated whether intensity modulated proton therapy (IMPT) would further reduce dose to cardiac substructures for patients with mediastinal lymphoma.

Patients and Methods

Twenty-one patients with mediastinal lymphoma were enrolled and underwent electrocardiogram-gated computed tomography angiography during or shortly after simulation for radiotherapy planning. Thirteen patients with delineated cardiac substructures underwent comparative planning with both IMPT and IMRT. Plans were normalized for equivalent (95%) target volume coverage for treatment comparison.

Results

Thirteen patients met criteria for this study. The median size of the mediastinal lymphadenopathy was 7.9 cm at the greatest diameter. Compared with IMRT-CSS, IMPT-CSS significantly reduced mean dose to all cardiac substructures, including 3 coronary arteries and 4 cardiac valves. Use of IMPT significantly reduced average whole-heart dose from 9.6 to 4.9 Gy (P < .0001), and average mean lung dose was 9.7 vs 5.8 Gy (P < .0001). Prospectively defined clinically meaningful improvement was observed in at least 1 coronary artery in 9 patients (69%), at least 1 cardiac valve in 10 patients (77%), and whole heart in all 13 patients.

Conclusions

For patients with mediastinal lymphoma, IMPT-CSS treatment planning significantly reduced radiation dose to cardiac substructures. The significant improvements outlined in this study for proton therapy suggest possible clinical improvement in alignment with previous analyses of CSS optimization.

Cardiovascular Magnetic Resonance Imaging: Identifying the Effects of Cancer Therapy

The era of modern oncology incorporates an ever-evolving personalized approach to hematological malignancies and solid tumors. As a result, patient survival rates have, in part, substantially improved, depending on the specific type of underlying malignancy. However, systemic therapies may come along with potential cardiotoxic effects resulting in heart failure with increased morbidity and mortality. Ultimately, patients may survive their malignancy but die as a result of cancer treatment. Cardiovascular magnetic resonance imaging has long been in use for the assessment of function and tissue characteristics in patients with various nonischemic cardiac diseases. Besides an introductory overview on the general definition of cardiotoxicity including potential underlying mechanisms, this review provides insight into the application of various cardiovascular magnetic resonance imaging techniques in the setting of cancer therapy-related cardiac and vascular toxicity. Early identification of cardiotoxic effects may allow for on-time therapy adjustment and/or cardioprotective measures to avoid subsequent long-term heart failure with increased mortality.

Thoracic radiotherapy as a risk factor for heart ischemia in subjects treated with chest irradiation and chemotherapy and without classic cardiovascular RISK factors

BACKGROUND AND PURPOSE

Radiation Induced Heart Disease (RIHD) represents a late effect of chest irradiation, contributing in increasing mortality rate in oncological patients by affecting pericardium, myocardium, valvs and coronaries. Currently, regarding the risk of Coronary Artery Disease (CAD), a cardiological screening involving exercise stress electrocardiography after 5-10 years from radiotherapy is advised. We sought to determine the rate of ischemia at exercise stress electrocardiography in a population of patients without cardiovascular risk factors who sustained radiotherapy, using a cohort of patients presenting with at least one cardiovascular risk factor as control group.

DESIGN AND METHODS

A population of 115 patients who sustained chest irradiation (and associated chemotherapy), presenting without classic cardiovascular risk factors or typical symptoms suggesting CAD, was evaluated with exercise stress electrocardiography. 135 patients with at least one risk factor for cardiovascular disease candidate to stress testing for primary prevention or for atypical symptoms served as control group.

RESULTS

The cohort of irradiated patients without classical cardiovascular risk factors is younger (48.7 ± 10.1 vs 60.5 ± 10.8 years, p < 0.001) and presents a lower percentage of males when compared with the control group. In this latter group 25.9% of subjects has diabetes, 62.9% dyslipidaemia, 67.4% hypertension and 19.2% actively smoke. Despite this important differences regarding classic cardiovascular risk factors, no significant differences were found in the number of positive exercise stress electrocardiography (10.4 vs 5.9%, p = ns).

CONCLUSIONS

Chest irradiation represents a strong cardiovascular risk factor. In fact, prevalence of positive ECG-stress test is not different (nor higher and nor lower) in irradiated subjects without cardiovascular risk and not irradiated patients with classic cardiovascular risk.

Survivorship, Version 2.2018, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Survivorship provide screening, evaluation, and treatment recommendations for common physical and psychosocial consequences of cancer and cancer treatment to help healthcare professionals who work with survivors of adult-onset cancer in the posttreatment period. This portion of the guidelines describes recommendations regarding the management of anthracycline-induced cardiotoxicity and lymphedema. In addition, recommendations regarding immunizations and the prevention of infections in cancer survivors are included.

Association between cardiovascular disease and a history of cancer in patients with chest pain on the fast track outpatient clinic

Background

The purpose of this study is to investigate the prevalence of a history of malignancy in patients with chest pain who were referred for computed tomography angiography as well as the long-term survival and cardiovascular outcomes, including coronary artery disease (CAD) and coronary artery calcium (CAC) percentiles of cancer survivors. These data are relevant since it is unknown how cancer survivors, who underwent cardio-toxic therapies, should be monitored.

Methods

We analysed all patients with chest pain, who came to the outpatient clinic and underwent computed tomography angiography. The primary study endpoint was long-term survival. The secondary endpoints included CAD on computed tomography angiogram (CTA), CAC percentiles, suspected and confirmed malignancy on CTA, and other accidental findings on CTA.

Results

Of all 1,892 patients included in the analyses, 133 (7%) had a history of malignancy and 1,759 (93%) did not. Mortality rates were higher for the cancer survivors (6.5% vs 20.9% after ten years, p < 0.001). The multivariable Cox regression model also showed higher mortality for cancer survivors after ten years (adjusted hazard ratio 2.48 [95% confidence interval: 1.58–3.90]). CAD did not differ between both groups. CAC percentiles were higher in cancer survivors (p = 0.037). Cancer survivors had more suspected malignancies (3.8% vs 0.5%; p = 0.001) and also more confirmed malignancies on CTA (3.0% vs 0.1%; p < 0.001).

Conclusions

Cancer survivors have higher mortality rates, no difference in CAD on CTA, higher CAC percentiles and more often malignancy on CTA compared with patients without a cancer history.

Electronic supplementary material

The online version of this article (10.1007/s12471-019-1268-8) contains supplementary material, which is available to authorized users.

Acute Coronary Syndrome in Cancer Patients

Cardiologists are seeing an increasing number of oncology patients every day, and acute coronary syndrome (ACS) is one of the problems patients encounter during follow-up. Cardio-oncology is the care of patients with cancer and cardiovascular disease, whether overt or occult, already established or acquired during treatment. Cardiovascular complications can occur acutely during or shortly after treatment and persist as long-term effects for months to years after treatment. As a delayed effect of cancer treatment, cardiovascular damage can occur months to years after the initial treatment. Vasospasm, thrombosis, and radiation-induced cardiovascular diseases can all cause ACS. Careful surveillance of ACS symptoms and regular screening during follow-up of patients with malignancy are suggested. In this review, we summarize the ACS we usually encounter during a range of cancer treatments or post cancer survival by providing illustrative case examples.

Interventional Cardio-Oncology: Adding a New Dimension to the Cardio-Oncology Field

The management of cardiovascular disease in patients with active cancer presents a unique challenge in interventional cardiology. Cancer patients often suffer from significant comorbidities such as thrombocytopenia and coagulopathic and/or hypercoagulable states, which complicates invasive evaluation and can specifically be associated with an increased risk for vascular access complications. Furthermore, anticancer therapies cause injury to the vascular endothelium as well as the myocardium. Meanwhile, improvements in diagnosis and treatment of various cancers have contributed to an increase in overall survival rates in cancer patients. Proper management of this patient population is unclear, as cancer patients are largely excluded from randomized clinical trials on percutaneous coronary intervention (PCI) and national PCI registries. In this review, we will discuss the role of different safety measures that can be applied prior to and during these invasive cardiovascular procedures as well as the role of intravascular imaging techniques in managing these high risk patients.

How to prevent and manage radiation-induced coronary artery disease

Radiation-induced coronary heart disease (RICHD) is the second most common cause of morbidity and mortality in patients treated with radiotherapy for breast cancer, Hodgkin's lymphoma and other prevalent mediastinal malignancies. The risk of RICHD increases with radiation dose. Exposed patients may present decades after treatment with manifestations ranging from asymptomatic myocardial perfusion defects to ostial, triple-vessel disease and sudden cardiac death. RICHD is insidious, with a long latency and a tendency to remain silent late into the disease course. Vessel involvement is often diffuse and is preferentially proximal. The pathophysiology is similar to that of accelerated atherosclerosis, characterised by the formation of inflammatory plaque with high collagen and fibrin content. The presence of conventional risk factors potentiates RICHD, and aggressive risk factor management should ideally be initiated prior to radiation therapy. Stress echocardiography is more sensitive and specific than myocardial perfusion imaging in the detection of RICHD, and CT coronary angiography shows promise in risk stratification. Coronary artery bypass grafting is associated with higher risks of graft failure, perioperative complications and all-cause mortality in patients with RICHD. In most cases, the use of drug-eluting stents is preferable to surgical intervention, bare metal stenting or balloon-angioplasty alone.

Acquired Natural Killer Cell Dysfunction in the Tumor Microenvironment of Classic Hodgkin Lymphoma

An understanding of interactions within the tumor microenvironment (TME) of classic Hodgkin lymphoma (cHL) has helped pave the way to novel immunotherapies that have enabled dormant and tumor-tolerant immune cells to be reactivated. The immunosuppressive nature of the TME in cHL specifically inhibits the proliferation and activity of natural killer (NK) cells, which contributes to tumor immune-escape mechanisms. This deficiency of NK cells begins at the tumor site and progresses systemically in patients with advanced disease or adverse prognostic factors. Several facets of cHL account for this effect on NK cells. Locally, malignant Reed-Sternberg cells and cells from the TME express ligands for inhibitory receptors on NK cells, including HLA-E, HLA-G, and programmed death-ligand 1. The secretion of chemokines and cytokines, including soluble IL-2 receptor (sCD25), Transforming Growth Factor-β, IL-10, CXCL9, and CXCL10, mediates the systemic immunosuppression. This review also discusses the potential reversibility of quantitative and functional NK cell deficiencies in cHL that are likely to lead to novel treatments.

Radiation-Induced Cardiovascular Disease

PURPOSE OF REVIEW

Thoracic radiation therapy is an effective treatment for several malignancies, such as Hodgkin's lymphoma and breast cancer. Over the years, however, the incidence of cardiovascular events has increased in these patients, notably in younger survivors who do not have traditional risk factors. This review summarizes the pathology, incidence, clinical presentation, and management of cardiac events after radiation therapy.

RECENT FINDINGS

Mediastinal radiation therapy accelerates the atherosclerosis process, resulting in early onset coronary artery disease. Valvular disease due to radiation therapy typically affects the left-sided valves, with aortic regurgitation being the most common. Rarely, it may lead to aortic stenosis requiring surgical interventions. Pericardial involvement includes acute and chronic pericardial disease and pericardial effusion. New studies are investigating the prevalence and pathogenesis of autonomic dysfunction in cancer survivors who have undergone mediastinal and neck radiation. Radiation therapy itself causes vascular endothelial dysfunction, resulting in clinical cardiovascular events, manifesting many years after completion of therapy. There remains little guidance regarding screening and therapies to prevent cardiovascular events in this population.

Emerging Cardiac Imaging Modalities for the Early Detection of Cardiotoxicity Due to Anticancer Therapies

The undeniable advances in the field of oncology have finally led to a decrease in overall cancer-related mortality. However, this population of long-term cancer survivors is now facing a shift toward a substantial increase in cardiovascular morbidity and mortality. Because the development of overt cardiotoxicity can be associated with poor outcomes, preclinical identification of cardiac toxicity is important. This will promote early instauration of treatments to prevent overt heart dysfunction and allow oncologists to continue cancer therapy in an uninterrupted manner. Surveillance strategies for the early detection of cardiac injury include cardiac imaging and biomarkers during treatment. In this review, we outline existing cardiac imaging modalities to detect myocardial changes in patients undergoing cancer treatment and in survivors, and their strengths and limitations.

Hodgkin lymphoma: Late effects of treatment and guidelines for surveillance

Long-term survivors of Hodgkin lymphoma (HL) are at risk for a range of late effects, with second malignant neoplasm and cardiovascular diseases being the leading causes of death in these patients. The excess risks remain significantly elevated decades after treatment, and are clearly associated with extent of treatment exposures. Other late effects have also been identified, such as pulmonary dysfunction, endocrinopathies, muscle atrophy, and persistent fatigue. Systemic documentation of late effects and recognition of treatment- and patient-related risk factors are important, as they inform optimal surveillance and risk-reduction strategies, as well as guide therapeutic modifications in newly diagnosed patients to minimize treatment-related complications. As HL therapy evolves over time, with adoption of novel agents and contemporary treatment techniques, late effect risks and follow-up recommendations need to be continuously updated.

Modulation of cardiovascular toxicity in Hodgkin lymphoma: potential role and mechanisms of aerobic training

Hodgkin lymphoma (HL) outcomes have improved due to advances in cancer treatment. However, HL survivors remain at increased risk for cardiovascular (CV) morbidity and mortality related to the long-term cardiotoxicity of HL treatment, particularly anthracycline chemotherapy and mediastinal radiotherapy. The role of aerobic training for the prevention of CV disease in the general population has been well established. However the safety and efficacy of aerobic training on CV outcomes has not been well studied in HL survivors. The purpose of this paper is to provide an up-to-date summary of the treatment-related adverse CV effects in HL survivors, review the CV benefits of exercise and review the limited evidence on the potential CV benefit of aerobic training in HL survivors.

Risks and diagnosis of coronary artery disease in Hodgkin lymphoma survivors

Higher mortality rates are reported because of cardiovascular diseases in individuals living in industrialized areas of the World. In cancer patients, cardiotoxic chemotherapeutic agents and/or mediastinal radiotherapy are additional risk factors for the development of coronary artery disease. An improved survival rate for patients with Hodgkin lymphoma was reported in recent decades. Determining and handling the long-term effects of cancer treatment have become more important nowadays, parallel to the good results reached in survival rates. Mediastinal radiotherapy and cardiotoxic chemotherapeutic agents are routinely used to treat Hodgkin lymphoma but are commonly associated with a variety of cardiovascular complications. Drugs used in cancer treatment and radiotherapy may cause deleterious effects on contractile capacity and conduction system of the heart. Approximately ten years after the completion of all therapies, the cardiovascular disease risk peaks in patients who survived from Hodgkin lymphoma. The value of coronary computed tomography angiography as a diagnostic tool in determining coronary artery disease as early as possible is underlined in this review, in patients who are in remission and carry the risk of coronary artery disease probably because of chemo/radiotherapy used in their treatment. Survivors of Hodgkin lymphoma especially treated with combined chemoradiotherapy at younger ages are candidates for coronary computed tomography angiography.