Symptomatic coronary artery disease after mantle irradiation for Hodgkin's disease

Overview of cardiac toxicity from radiation therapy

Radiotherapy is an essential part of treatment for many patients with thoracic cancers. However, proximity of the heart to tumour targets can lead to cardiac side effects, with studies demonstrating link between cardiac radiation dose and adverse outcomes. Although reducing cardiac dose can reduce associated risks, most cardiac constraint recommendations in clinical use are generally based on dose to the whole heart, as dose assessment at cardiac substructure levels on individual patients has been limited historically. Furthermore, estimation of an individual's cardiac risk is complex and multifactorial, which includes radiation dose alongside baseline risk factors, and the impact of systemic therapies. This review gives an overview of the epidemiological impact of cancer and cardiac disease, risk factors contributing to radiation-related cardiotoxicity, the evidence for cardiac side effects and future directions in cardiotoxicity research. A better understanding of the interactions between risk factors, balancing treatment benefit versus toxicity and the ongoing management of cardiac risk is essential for optimal clinical care. The emerging field of cardio-oncology is thus a multidisciplinary collaborative effort to enable better understanding of cardiac risks and outcomes for better-informed patient management decisions.

Consequences of ionizing radiation exposure to the cardiovascular system

Ionizing radiation is widely used in various industrial and medical applications, resulting in increased exposure for certain populations. Lessons from radiation accidents and occupational exposure have highlighted the cardiovascular and cerebrovascular risks associated with radiation exposure. In addition, radiation therapy for cancer has been linked to numerous cardiovascular complications, depending on the distribution of the dose by volume in the heart and other relevant target tissues in the circulatory system. The manifestation of symptoms is influenced by numerous factors, and distinct cardiac complications have previously been observed in different groups of patients with cancer undergoing radiation therapy. However, in contemporary radiation therapy, advances in treatment planning with conformal radiation delivery have markedly reduced the mean heart dose and volume of exposure, and these variables are therefore no longer sole surrogates for predicting the risk of specific types of heart disease. Nevertheless, certain cardiac substructures remain vulnerable to radiation exposure, necessitating close monitoring. In this Review, we provide a comprehensive overview of the consequences of radiation exposure on the cardiovascular system, drawing insights from various cohorts exposed to uniform, whole-body radiation or to partial-body irradiation, and identify potential risk modifiers in the development of radiation-associated cardiovascular disease.

Radiation-Induced Heart Disease

Cancer incidence and survivorship have had a rising tendency over the last two decades due to better treatment modalities. One of these is radiation therapy (RT), which is used in 20-55% of cancer patients, and its basic principle consists of inhibiting proliferation or inducing apoptosis of cancer cells. Classically, photon beam RT has been the mainstay therapy for these patients, but, in the last decade, proton beam has been introduced as a new option. This newer method focuses more on the tumor and affects less of the surrounding normal tissue, i.e., the heart. Radiation to the heart is a common complication of RT, especially in patients with lymphoma, breast, lung, and esophageal cancer. The pathophysiology is due to changes in the microvascular and macrovascular milieu that can promote accelerated atherosclerosis and/or induce fibrosis of the myocardium, pericardium, and valves. These complications occur days, weeks, or years after RT and the risk factors associated are high radiation doses (>30 Gy), concomitant chemotherapy (primarily anthracyclines), age, history of heart disease, and the presence of cardiovascular risk factors. The understanding of these mechanisms and risk factors by physicians can lead to a tailored assessment and monitorization of these patients with the objective of early detection or prevention of radiation-induced heart disease. Echocardiography is a noninvasive method which provides a comprehensive evaluation of the pericardium, valves, myocardium, and coronaries, making it the first imaging tool in most cases; however, other modalities, such as computed tomography, nuclear medicine, or cardiac magnetic resonance, can provide additional value.

Coronary artery disease surveillance among childhood, adolescent and young adult cancer survivors: A systematic review and recommendations from the International Late Effects of Childhood Cancer Guideline Harmonization Group

BACKGROUND

Coronary artery disease (CAD) is a concerning late outcome for cancer survivors. However, uniform surveillance guidelines are lacking.

AIM

To harmonise international recommendations for CAD surveillance for survivors of childhood, adolescent and young adult (CAYA) cancers.

METHODS

A systematic literature review was performed and evidence graded using the Grading of Recommendations, Assessment, Development and Evaluation criteria. Eligibility included English language studies, a minimum of 20 off-therapy cancer survivors assessed for CAD, and 75% diagnosed prior to age 35 years. All study designs were included, and a multidisciplinary guideline panel formulated and graded recommendations.

RESULTS

32 of 522 identified articles met eligibility criteria. The prevalence of CAD ranged from 0 to 72% and was significantly increased compared to control populations. The risk of CAD was increased among survivors who received radiotherapy exposing the heart, especially at doses ≥15 Gy (moderate-quality evidence). The guideline panel agreed that healthcare providers and CAYA cancer survivors treated with radiotherapy exposing the heart should be counselled about the increased risk for premature CAD. While the evidence is insufficient to support primary screening, monitoring and early management of modifiable cardiovascular risk factors are recommended. Initiation and frequency of surveillance should be based on the intensity of treatment exposures, family history, and presence of co-morbidities but at least by age 40 years and at a minimum of every 5 years. All were strong recommendations.

CONCLUSION

These systematically assessed and harmonised recommendations for CAD surveillance will inform care and guide research concerning this critical outcome for CAYA cancer survivors.

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.

Modern Radiotherapy and Risk of Cardiotoxicity

Despite the advancements of modern radiotherapy, radiation-induced heart disease remains a common cause of morbidity and mortality amongst cancer survivors. This review outlines the basic mechanism, clinical presentation, risk stratification, early detection, possible mitigation, and treatment of this condition.

Cardiovascular Risk Reduction in High-Risk Pediatric Patients: A Scientific Statement From the American Heart Association

This scientific statement presents considerations for clinical management regarding the assessment and risk reduction of select pediatric populations at high risk for premature cardiovascular disease, including acquired arteriosclerosis or atherosclerosis. For each topic, the evidence for accelerated acquired coronary artery disease and stroke in childhood and adolescence and the evidence for benefit of interventions in youth will be reviewed. Children and adolescents may be at higher risk for cardiovascular disease because of significant atherosclerotic or arteriosclerotic risk factors, high-risk conditions that promote atherosclerosis, or coronary artery or other cardiac or vascular abnormalities that make the individual more vulnerable to the adverse effects of traditional cardiovascular risk factors. Existing scientific statements and guidelines will be referenced when applicable, and suggestions for risk identification and reduction specific to each setting will be described. This statement is directed toward pediatric cardiologists, primary care providers, and subspecialists who provide clinical care for these young patients. The focus will be on management and justification for management, minimizing information on pathophysiology and epidemiology.

Age at Exposure to Radiation Determines Severity of Renal and Cardiac Disease in Rats

Radiotherapy with sparsely ionizing photons is a cornerstone of successful cancer treatment. Age at time of exposure to radiation is known to influence biological outcomes for many end points. The effect of dose and age at exposure upon the occurrence of radiogenic cardiovascular disease is poorly understood. The goal of this work was to determine the response of maleWAG/RijCmcr rats at 6 months of age to gamma rays, and at 6 months or 6 weeks of age to X rays, using clinically relevant biomarkers of cardiovascular disease and kidney injury. Overall, there were significant radiation-induced effects on the levels of bicarbonate (P=0.0016), creatinine (P=0.0002), calcium (P = 0.0009), triglycerides (P = 0.0269) and blood urea nitrogen, albumin, protein, AST, alkaline phosphatase, total cholesterol and HDL (all P < 0.0001). Of those variables with a significant radiation-dose effect, there were significant modifications by age at time of exposure for bicarbonate (P = 0.0033), creatinine (P = 0.0015), AST (P = 0.0040), total cholesterol (P = 0.0006) and blood urea nitrogen, calcium, albumin, protein, alkaline phosphatase and HDL (all P < 0.0001). Cardiac perivascular collagen content was significantly increased in rats that were 8.0 Gy X-ray irradiated at 6 weeks of age (P < 0.047) but not at 6 months of age. While systemic blood pressure was elevated in both cohorts after 8.0 Gy X-ray irradiation (compared to agematched sham-irradiated controls), the magnitude of the increase above baseline was greater in the younger rats (P < 0.05). These findings indicate that dose and age at time of irradiation determine the timeline and severity of cardiac and renal injury.

[Post Radiotherapy Lesions of the Heart Valves. Principles of Diagnosis and Results of Treatment]

BACKGROUND

The use of radiation therapy for the treatment of tumors of the chest сan lead to the development of cardiac pathology, including that of the valves and coronary arteries.

STUDY AIM

to analyze the specifics of post-radiation lesions of the valvular apparatus and coronary arteries, and to assess the immediate results and risks of surgical correction of detected defects. Materials and  methods. In the Emergency department of surgery of acquired heart disease of A. N. Bakulev National Medical Research Center of Cardiovascular Surgery in the period from 2004 to 2017 were examined and operated 46 patients aged 35-81 years (mean age 56±12.4 years, 80 % women). The period from primary irradiation of the chest to surgical treatment of valvular pathology ranged from 4 to 40 years. Indications for thoracic radiotherapy were Hodgkin's lymphoma in 23 patients (50 %), breast cancer - in 20 (43 %).

RESULTS

Stenosis of the aortic valve was the leading defect in 42 patients (91 %). According to coronary angiography, coronary artery disease was diagnosed in 31 patients (67 %). Isolated aortic valve prosthesis was performed in 14 (30 %) patients, other operations were combined. Hospital mortality was 11 % (5 patients). There were no deaths among patients who underwent radiation therapy after mastectomy. Main nonlethal complications were: pericardial effusion in 6 patients (13 %), hydrothorax requiring repeated pleural punctures in 5 patients (11 %).

CONCLUSION

The variety of clinical manifestations of radiation heart disease and its progressive nature emphasize the need for long-term dynamic observation of patients after thoracic irradiation in order to timely identify the pathology and eliminate the risk of sudden cardiac complications and the development of severe heart failure decompensation.

Late-onset cardiomyopathy among survivors of childhood lymphoma treated with anthracyclines: a systematic review

Medical advances in pediatric oncology have led to increases in survival but the long-term adverse effects of treatment in childhood cancer survivors have not yet been examined in depth. In this systematic review, we aimed to study the prevalence and risk factors of late-onset cardiomyopathy (LOCM) among survivors of childhood lymphoma treated with anthracyclines. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines we searched Pubmed/Medline, abstracted data and rated studies on quality regarding late-onset (>1 year following treatment) cardiotoxicity of anthracyclines in survivors of childhood lymphoma. Across 22 identified studies, the prevalence of anthracycline-induced LOCM among survivors of childhood lymphoma ranges from 0 to 40%. Anthracycline dose, administration and dose of mediastinal radiation, patient's age and era of diagnosis and evaluation, follow-up duration as well as disease relapse have been reported as risk factors for LOCM, whereas administration of dexrazoxane seems to act protectively. There was significant between-study heterogeneity with regards to lymphoma subtypes, follow-up duration, definition of outcomes, and anthracycline-based treatment protocols. The rates of anthracycline-induced LOCM among survivors of childhood lymphoma are high and dependent on study design. Future studies should explore whether modifying risk factors and suggested supportive care could decrease its prevalence among childhood lymphoma survivors. Until then, lifelong follow-up of these patients aiming to determinate the earliest signs of cardiac dysfunction is the most important measure towards primordial prevention of LOCM.

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.

Cardiac-Sparing Whole Lung IMRT in Patients With Pediatric Tumors and Lung Metastasis: Final Report of a Prospective Multicenter Clinical Trial

PURPOSE

A prospective clinical trial was conducted for patients undergoing cardiac sparing (CS) whole lung irradiation (WLI) using intensity modulated radiation therapy (IMRT). The 3 trial aims were (1) to demonstrate the feasibility of CS IMRT with real-time central quality control; (2) to determine the dosimetric advantages of WLI using IMRT compared with standard anteroposterior (AP) techniques; and (3) to determine acute tolerance and short-term efficacy after a protocol-mandated minimum 2-year follow-up for all patients.

METHODS AND MATERIALS

All patients underwent a 3-dimensional chest computed tomography scan and a contrast-enhanced 4-dimensional (4D) gated chest computed tomography scan using a standard gating device. The clinical target volume was the entire bilateral 3-dimensional lung volume, and the internal target volume was the 4D minimum intensity projection of both lungs. The internal target volume was expanded by 1 cm to get the planning target volume. All target volumes, cardiac contours, and treatment plans were centrally reviewed before treatment. The different cardiac volumes receiving percentages of prescribed radiation therapy (RT) doses on AP and IMRT WLI plans were estimated and compared.

RESULTS

The target 20 patients were accrued in 2 years. Median RT dose was 15 Gy. Real-time central quality assurance review and plan preapproval were obtained for all patients. WLI using IMRT was feasible in all patients. Compared with standard AP WLI, CS IMRT resulted in a statistically significant reduction in radiation doses to the whole heart, atria, ventricles, and coronaries. One child developed cardiac dysfunction and pulmonary restrictive disease 5.5 years after CS IMRT (15 Gy) and doxorubicin (375 mg/m²). The 2- and 3-year lung metastasis progression-free survival was 65% and 52%, respectively.

CONCLUSIONS

We have demonstrated the feasibility of WLI using CS IMRT and confirmed the previously reported advantages of IMRT, including superior cardiac protection and superior dose coverage of 4D lung volumes. Further studies are required to establish the efficacy and safety of this irradiation technique.

Dosimetric evaluation of right coronary artery in radiotherapy for breast cancer

Comparison with control groups of untreated patients suggests that right-breast-cancer patients who receive radiotherapy have a higher rate of heart disease. Dose constraint for heart has been established to minimize radiotherapy-induced cardiotoxicity during left breast cancer treatment. Additionally, it is suggested to minimize the dosage on left anterior descending (LAD) artery. Right coronary artery (RCA), is the second largest artery, after left main coronary artery, supplying the heart. A dose evaluation study is not present for RCA; the proximal part of which is included in the irradiation field during breast cancer treatment of right breast. To investigate the presence of a correlation, doses resulting from right and left breast radiotherapy on proximal RCA (pRCA), LAD, and heart are evaluated in this study. Forty breast cancer patients who went under breast-conserving surgery are the subject of this study. Four groups were established; right breast, right breast and internal mammary (IM), left breast and left breast, and IM. pRCA, LAD, and heart volumes were contoured for each group on the planning tomographies. Resultant doses of tangential fields planning on these volumes were compared using dose-volume histograms. Mean and maximum doses of pRCA were statistically compared between groups. The highest mean and maximum point doses (192 to 284 cGy) were found in the right breast + IM group (p < 0.05). The mean and maximum doses only in the right breast and left breast + IM group did not differ statistically. However, the mean and maximum pRCA doses in these 2 groups were higher than only the left breast group (p < 0.05). pRCA receives high doses during radiotherapy of right and left breast especially if IM is included. This may predispose to coronary artery disease.

Radiation Therapy Is Associated With an Increased Incidence of Cardiac Events in Patients with Small Cell Lung Cancer

PURPOSE

Cardiac radiation dose was a predictor of inferior overall survival in the Radiation Therapy Oncology Group 0617 non-small cell lung cancer trial. We examined the association between radiation therapy (RT) and cardiac events (CE) for patients with small cell lung cancer (SCLC).

METHODS AND MATERIALS

The US population-based Surveillance, Epidemiology, and End Results Program and Medicare claims databases were queried for rates of CE among patients with SCLC treated with chemotherapy (CTX) ± RT. Propensity score matching (PSM) and multivariate analysis were conducted. Patients were matched for actual/theoretical RT start date (to prevent immortal time bias) and then full PSM balanced clinical characteristics. Cumulative incidence function curves were generated.

RESULTS

From 2000 to 2011, 7060 patients were included: 2892 limited-stage SCLC (LS-SCLC) and 4168 extensive-stage SCLC. Grouping LS-SCLC and extensive-stage SCLC together, the incidence of CE for the CTX + RT and CTX-only groups was 44.1% versus 39% at 60 months (P = .008). After PSM (5286 patients), the incidence of CE for the CTX + RT and CTX-only groups was 43% versus 38.6% at 60 months (P = .033). Analysis of only LS-SCLC (2016 patients) demonstrated that the incidence of CE for CTX + RT versus CTX-only groups was 50.3% versus 42% at 60 months (P = .0231). Multivariate analysis again demonstrated an association between CE and RT (hazard ratio 1.20; 95% confidence interval 1.06-1.37; P = .005). After PSM (1614 patients), the incidence of CE for CTX + RT versus CTX-only groups was 51.7% versus 41.6% at 60 months (P = .0042).

CONCLUSIONS

Patients with SCLC are at significant risk of developing CE posttreatment; RT is associated with an absolute increase in the rate of CE at 5 years of approximately 5% for all patients with SCLC and up to 10% for patients with LS-SCLC. Cardiac risk management and cardiac-sparing RT techniques should be further evaluated for patients with SCLC.

Radiation-Induced Coronary Artery Disease in Young Patients

Exposure to radiotherapy has been shown to accelerate myocardial damage or injury to the cardiac vasculature. Accelerated coronary artery disease (CAD) is one of the main manifestations of cardiac disease in patients who undergo mediastinal radiation therapy. We present the cases of three young patients who developed severe CAD secondary to remote mediastinal radiotherapy.

Radiation Therapy Induced Cardiovascular Disease

Contemporary treatment modalities for malignancy including radiation therapy have led to improved survival. However treatment related complications manifesting later in life including cardiovascular disease has led to survivors exhibiting a lower long term survival rate, when compared to age matched controls. This narrative review will discuss the pathophysiology, risk factors, clinical presentation, management and preventative techniques related to radiotherapy-induced cardiotoxicity.

Normal Tissue Complications following Hypofractionated Chest Wall Radiotherapy in Breast Cancer Patients and Their Correlation with Patient, Tumor, and Treatment Characteristics

INTRODUCTION

Normal tissue complications following chest wall radiotherapy (RT) are inevitable, and the long-term data on hypofractionation are still limited. To quantify the late effects of hypofractionated RT on cardiac, pulmonary, brachial plexus, and regional lymphatics and their correlation with patient, tumor, and treatment characteristics is the main objective of this study.

MATERIALS AND METHODS

Two hundred and sixteen breast cancer patients following mastectomy were treated with hypofractionated schedules either 40 Gy in 15 fractions or 42.5 Gy in 16 fractions. Common Toxicity Criteria version 3.0 was utilized to quantify the late effects of hypofractionation on cardiac, pulmonary, brachial plexus, and lymphedema at a maximum follow-up of 5 years.

RESULTS

Median follow-up was 42 months. Median age was 49 years. 14.8% developed ≥Grade (Gr) 2 late cardiac toxicity. 10.2% developed ≥Gr2 late pulmonary toxicity. There were 28.7% patients who developed ≥Gr2 lymphedema. Sixty-seven out of 216 patients had symptomatic brachial plexopathy at 5-year follow-up. Variables found to increase the incidence of these adverse events included smoking, hypertension, diabetes mellitus, body mass index ≥25, extent of axillary dissection, and use of supraclavicular field.

CONCLUSION

Hypofractionation leads to increased risk of normal tissue complications partly influenced by some patient- and treatment-related factors, but these were manageable and minimally disabling.

Cardiac Outcomes in Adult Survivors of Childhood Cancer Exposed to Cardiotoxic Therapy: A Cross-sectional Study

BACKGROUND

Studies of cardiac disease among adult survivors of childhood cancer have generally relied on self-reported or registry-based data.

OBJECTIVE

To systematically assess cardiac outcomes among survivors of childhood cancer.

DESIGN

Cross-sectional study.

SETTING

St. Jude Children's Research Hospital.

PATIENTS

1853 adult survivors of childhood cancer, aged 18 years or older, who received cancer-related cardiotoxic therapy at least 10 years earlier.

MEASUREMENTS

Baseline history and physical examination, fasting metabolic and lipid panels, echocardiography, electrocardiography, and 6-minute walk test.

RESULTS

One half of the survivors (52.3%) were men with a median age of 8 years (range, 0 to 24 years) at cancer diagnosis and 31 years (range, 18 to 60 years) at evaluation. Cardiomyopathy was present in 7.4% survivors (newly identified at the time of evaluation in 4.7%), coronary artery disease in 3.8% (newly identified in 2.2%), valvular regurgitation or stenosis in 28.0% (newly identified in 24.8%), and conduction or rhythm abnormalities in 4.4% (newly identified in 1.4%). Nearly all survivors were asymptomatic. The prevalence of cardiac conditions increased with age at evaluation, ranging from 3% to 24% among survivors aged 30 to 39 years to 10% to 37% among those aged 40 years or older. In multivariable analysis, survivors exposed to anthracycline doses of 250 mg/m2 or more had greater odds of cardiomyopathy (odds ratio, 2.7 [95% CI, 1.1 to 6.9]) than those who were not exposed. Survivors exposed to heart radiation also had increased odds of cardiomyopathy (odds ratio, 1.9 [CI, 1.1 to 3.7]) compared with those who were not exposed. Radiation exposure greater than 1500 cGy with any anthracycline exposure conferred the greatest odds for valve findings.

LIMITATIONS

Sixty-one percent of survivors exposed to anthracycline chemotherapy or cardiac-directed radiation participated. A comparison group and longitudinal assessments were not available.

CONCLUSION

Cardiovascular screening identified considerable subclinical disease among adult survivors of childhood cancer.

PRIMARY FUNDING SOURCE

National Cancer Institute, American Lebanese Syrian Associated Charities.

Whole Lung Irradiation in Adults with Metastatic Ewing Sarcoma: Practice Patterns and Implications for Treatment

Background. Whole lung irradiation (WLI) is a standard treatment component for children with metastatic Ewing Sarcoma (ES), but data on WLI for adults are sparse. Design. An email survey was sent to expert sarcoma-dedicated oncologists worldwide: An adult with excellent performance status presents with primary ES in the leg and multiple pulmonary metastases. The patient achieves complete radiographic response after chemotherapy and resection of the primary. Would you give bilateral WLI to (1) this adult patient?, (2) this patient if 20 years old (yo)?, (3) this patient if 45 yo?, or (4) this patient if 60 yo? Results. 38 experts responded, including 24 adult, 1 adolescent young adult, and 13 pediatric oncologists. 63%, 63%, 62%, and 50% of respondents offered WLI to the adult, 20-year-old, 45-year-old, and 60-year-old, respectively. Pediatric oncologists more likely endorsed WLI across all ages including the adult (P = 0.01), 20-year-old (P = 0.005), 45-year-old (P = 0.01), and 60-year-old (P = 0.08). There were no significant differences between medical and radiation oncologists or between European/Australian and American providers. Conclusions. Almost two-thirds of experts surveyed supported WLI for adults with metastatic ES up to age 45 and half supported WLI for a 60-year-old. Continued collaboration across adult and pediatric oncology is needed to define evidence-based strategies across the age spectrum.

Expert consensus for multi-modality imaging evaluation of cardiovascular complications of radiotherapy in adults: a report from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Cardiac toxicity is one of the most concerning side effects of anti-cancer therapy. The gain in life expectancy obtained with anti-cancer therapy can be compromised by increased morbidity and mortality associated with its cardiac complications. While radiosensitivity of the heart was initially recognized only in the early 1970s, the heart is regarded in the current era as one of the most critical dose-limiting organs in radiotherapy. Several clinical studies have identified adverse clinical consequences of radiation-induced heart disease (RIHD) on the outcome of long-term cancer survivors. A comprehensive review of potential cardiac complications related to radiotherapy is warranted. An evidence-based review of several imaging approaches used to detect, evaluate, and monitor RIHD is discussed. Recommendations for the early identification and monitoring of cardiovascular complications of radiotherapy by cardiac imaging are also proposed.

Expert consensus for multi-modality imaging evaluation of cardiovascular complications of radiotherapy in adults: a report from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Cardiac toxicity is one of the most concerning side effects of anti-cancer therapy. The gain in life expectancy obtained with anti-cancer therapy can be compromised by increased morbidity and mortality associated with its cardiac complications. While radiosensitivity of the heart was initially recognized only in the early 1970s, the heart is regarded in the current era as one of the most critical dose-limiting organs in radiotherapy. Several clinical studies have identified adverse clinical consequences of radiation-induced heart disease (RIHD) on the outcome of long-term cancer survivors. A comprehensive review of potential cardiac complications related to radiotherapy is warranted. An evidence-based review of several imaging approaches used to detect, evaluate, and monitor RIHD is discussed. Recommendations for the early identification and monitoring of cardiovascular complications of radiotherapy by cardiac imaging are also proposed.

Educational paper: decreasing the burden of cardiovascular disease in childhood cancer survivors: an update for the pediatrician

The cardiovascular impact of cancer therapies on the heart is one of the major concerns in the long-term follow-up of childhood cancer survivors (CCSs). Long-term cardiovascular effects include the development of left ventricular dysfunction resulting in congestive heart failure and ischemic heart disease, as well as valvular and pericardial disease. This is mainly ascribed to the cardiotoxic side effects of chemotherapeutic agents (especially anthracyclines) and radiotherapy, but other factors such as radiation and inflammation play a role in the effect of childhood cancer on the cardiovascular health. The most concerning effect is the high incidence of symptomatic heart failure in CCS patients treated with anthracyclines. More than 50 % of CCSs treated with anthracyclines develop asymptomatic left ventricular dysfunction after cancer therapy, with approximately 5 % developing clinical signs of heart failure during long-term follow-up. Once CCS patients develop congestive heart failure, prognosis is poor and is not influenced by current medical treatment strategies. To reduce the long-term burden of cardiovascular disease in pediatric cancer patients, a diversified approach will be necessary. In the acute phase, prevention of cardiac damage through the use of cardioprotective agents (e.g., dexrazoxane) or by administering less cardiotoxic chemotherapeutic agents is to be considered. A recent randomized trial suggested that the use of dexrazoxane reduced cardiac toxicity without affecting cancer outcomes. Especially patients requiring high doses of chemotherapeutic agents could benefit from this approach. Recent data suggest that genetic testing might identify patients at higher risk for cardiotoxicity. This seems mainly related to genes involved in drug metabolism. This would allow personalized approach adjusting chemotherapy based on cardiovascular risk profiling. This could be combined with newer monitoring strategies in the acute phase using newer echocardiographic techniques and biomarker screening to identify patients with early damage to the myocardium. For the long-term CCS cohort, early detection and treatment of early dysfunction prior to the development of congestive heart failure could potentially improve long-term outcomes. Promoting healthy lifestyles and controlling additional cardiovascular risk factors (e.g., obesity, diabetes, arterial hypertension) is an important task for every physician involved in the care of this growing cohort.

Cardiac complications after radical radiotherapy

Improvements in cancer therapy have led to increasing numbers of cancer survivors, and the long-term complications of these treatments are now becoming apparent. This article presents the current knowledge of adverse cardiovascular effects of radiotherapy to the chest. Medline literature searches relating to the cardiac complications of radiotherapy and subsequent prognosis were conducted. Potential adverse effects of mediastinal irradiation are numerous and can include coronary artery disease, pericarditis, cardiomyopathy, and valvular disease. Damage seems to be related to radiation dose, volume of irradiated heart, age at exposure, technique of chest irradiation, and patient-specific factors. The advent of technology and the newer sophisticated techniques in treatment planning and delivery are expected to decrease the incidence of cardiovascular diseases after radiation of the mediastinal structures. In any case, patients subjected to irradiation of the mediastinal structures require close multidisciplinary clinical monitoring.

Therapy-Related Late Adverse Events in Hodgkin’s Lymphoma

Hodgkin's lymphoma (HL) is one of the most curable hematologic diseases with an overall response rate over 80%. However, despite this therapeutic efficacy, HL survivors show a higher morbidity and mortality than other people of the same age because of long-term therapy-related events. In the last decades, many efforts have been made to reduce these effects through the reduction of chemotherapy dose, the use of less toxic chemotherapeutic agents, and the introduction of new radiation techniques. In this paper, we will describe the main long-term effects related to chemotherapy and radiotherapy for HL, the efforts to reduce toxicity made in the last years, and the clinical aspects which have to be taken into consideration in the followup of these patients.

Cardiac-sparing whole lung IMRT in children with lung metastasis

PURPOSE

To demonstrate the dosimetric advantages of cardiac-sparing (CS) intensity modulated radiation therapy (IMRT) in children undergoing whole lung irradiation (WLI).

METHODS AND MATERIALS

Chest CT scans of 22 children who underwent simulation with 3-dimensional (n=10) or 4-dimensional (n=12) techniques were used for this study. Treatment planning was performed using standard anteroposterior-posteroanterior (S-RT) technique and CS-IMRT. Left and right flank fields were added to WLI fields to determine whether CS-IMRT offered any added protection to normal tissues at the junction between these fields. The radiation dose to the lung PTV, cardiac structures, liver, and thyroid were analyzed and compared.

RESULTS

CS-IMRT had 4 significant advantages over S-RT: (1) superior cardiac protection (2) superior 4-dimensional lung planning target volume coverage, (3) superior dose uniformity in the lungs with fewer hot spots, and (4) significantly lower dose to the heart when flank RT is administered after WLI.

CONCLUSIONS

The use of CS-IMRT and 4-dimensional treatment planning has the potential to improve tumor control rates and reduce cardiac toxicity in children receiving WLI.

Radiation as a risk factor for cardiovascular disease

Abstract population are ubiquitous background radiation and medical exposure of patients. From the early 1980s to 2006, the average dose per individual in the United States for all sources of radiation increased by a factor of 1.7-6.2 mSv, with this increase due to the growth of medical imaging procedures. Radiation can place individuals at an increased risk of developing cardiovascular disease. Excess risk of cardiovascular disease occurs a long time after exposure to lower doses of radiation as demonstrated in Japanese atomic bomb survivors. This review examines sources of radiation (atomic bombs, radiation accidents, radiological terrorism, cancer treatment, space exploration, radiosurgery for cardiac arrhythmia, and computed tomography) and the risk for developing cardiovascular disease. The evidence presented suggests an association between cardiovascular disease and exposure to low-to-moderate levels of radiation, as well as the well-known association at high doses. Studies are needed to define the extent that diagnostic and therapeutic radiation results in increased risk factors for cardiovascular disease, to understand the mechanisms involved, and to develop strategies to mitigate or treat radiation-induced cardiovascular disease.

Behavioral and psychosocial program needs of young adult cancer survivors

Behavioral interventions for cancer survivors have historically targeted older adults or young adult survivors of childhood cancer. In this study, 18- to 39-year-olds diagnosed with cancer during young adulthood were interviewed to identify the types of behavioral and psychosocial programs needed. These young adult cancer survivors were also asked to identify potential barriers to program utilization. Participants expressed interest in programs targeting physical activity, relaxation, emotional support, provision of cancer-related and other information, and nutrition/weight loss. Emergent themes included the importance of choice, flexibility, convenience, and similarity to other program participants. Barriers to participation included practical barriers (e.g., limited time), lack of awareness of programs, health issues (e.g., fatigue), and psychosocial barriers (e.g., low motivation). Results highlight a range of unmet psychosocial and behavioral needs among young adult cancer survivors. This information can be used to develop interventions for this population.

Screening Hodgkin lymphoma survivors for radiotherapy induced cardiovascular disease

Long term prognosis of Hodgkin lymphoma (HL) survivors is affected by late toxicity of radiotherapy and chemotherapy. Cardiovascular complications of radiotherapy have been shown to have a great impact on the long term survival. The aim of this review is to summarize the available data on different screening modalities for cardiovascular disease and to suggest a screening program. Patients older than 45 years at HL diagnosis should be screened for coronary artery disease (CAD) starting 5 years after mediastinal radiotherapy; they are at increased risk of pre-existent atherosclerosis which can be accelerated by radiotherapy. Screening for CAD should start 10 years after radiotherapy in younger patients. The best screening modality for CAD is subject of discussion, based on the latest studies we suggest screening by Coronary artery calcium score measurements or CT-angiography. Valvular disorders should be looked for by echocardiography starting 10 years after radiotherapy. Electrocardiograms should be performed at each cardiovascular screening moment in order to detect arrhythmia's or conduction abnormalities. We suggest repeating these screening tests every 5 years or at onset of cardiovascular complaints; patients should be extensively instructed about signs and symptoms of cardiovascular disease. Furthermore traditional risk factors for cardiovascular disease should be carefully monitored and treated. We suggest determining a cardiovascular risk profile at diagnosis of HL in patients older than 45 years. In case of a high risk, treating HL without RT should be considered.

Late effects in the era of modern therapy for Hodgkin lymphoma

Extended-field and subtotal nodal radiation therapy (RT), developed in the 1960s, was the first reliably curative treatment for early-stage Hodgkin lymphoma (HL). However, the large volume of normal tissue irradiated resulted in significant delayed toxicity, including cardiac disease and second cancers (SCs). The 30-year cumulative incidence of heart disease among adult survivors receiving 40-45 Gy of extended-field or mantle RT is approximately 30%; the incidence of SCs is similar. Improving disease control while reducing the toxicity of treatment has been a major objective of HL trials for more than 2 decades. Contemporary involved-field RT (IFRT) reduces irradiated volumes and produces significant reductions in normal tissue dose compared with historic treatments. Recent data indicate that, compared with mantle RT, IFRT reduces the relative risk of breast cancer among young females receiving mediastinal RT by approximately 60% and also reduces cardiac dose. The recent transition to involved-node RT allows further reductions in normal tissue dose. Response-adapted therapy is being evaluated in clinical trials as a means of identifying those patients most likely to benefit from treatment reduction or intensification, enhanced screening will facilitate early intervention to reduce the clinical burden of late effects, and there is increasing interest in elucidating the genetic correlates of treatment toxicity.

Impaired vascular function in asymptomatic young adult survivors of Hodgkin Lymphoma following mediastinal radiation

BACKGROUND

Mediastinal radiation can accelerate atherosclerosis in Hodgkin lymphoma survivors (HLS), and early detection is optimal. Peripheral arterial tonometry (PAT), a non-invasive measure of endothelial function, is a surrogate marker of sub-clinical atherosclerosis. The objective of our study was to evaluate endothelial function in HLS and controls using PAT and to determine the influence of mediastinal radiation.

PROCEDURE

Cross-sectional evaluation was performed on 26 HLS aged 12-30 years who were a minimum of 2 years from therapy, and their healthy age and gender matched controls. Evaluation included assessment for cardiovascular risk factors and completion of the Habitual Activity Estimation Score (HAES) questionnaire to assess activity level. Endothelial Function was measured using PAT hyperemia ratios (PAT-HR).

RESULTS

HLS and controls were similar for baseline variables (mean age 23.3 +/- 5 yrs vs. 23.4 +/- 4.8 yrs, p = 0.92). HLS were on average 6.7 +/- 4.6 yrs post treatment. No differences in endothelial function or cardiovascular risk factors were observed between HLS and controls. However, impaired endothelial function, as evidenced by lower PAT-HR (1.67 +/- 0.39 vs. 2.03 +/- 0.37, p < 0.01) was seen in HLS (n = 13) who received mediastinal radiation (mean radiation dose 2,600 +/- 840 cGy) compared to controls.

CONCLUSIONS

Impaired endothelial function was preferentially observed in HLS who received mediastinal radiation, while no difference was observed between the HLS and control groups overall. This finding, assessed using a non invasive test of endothelial function, confirms that mediastinal radiation is an additional cardiovascular risk factor in this young cohort of patients. Further studies of endothelial function in this patient population are warranted.

A population-based study of cardiac morbidity among Hodgkin lymphoma patients with preexisting heart disease

The risk of cardiac hospitalization (CH) in Hodgkin lymphoma (HL) patients with preexisting heart disease was evaluated. Patients with HL were identified from a population-based registry (N = 3964). Data were abstracted from records of a randomly selected subcohort (N = 1096). A population-based registry was used to identify CH. Factors associated with CH and the incidence of CH after HL were estimated with competing risk models. Preexisting heart disease was the strongest predictor of posttreatment CH (hazard ratio = 3.98, P < .001) and significantly modified (P = .01) the effect of treatment on the risk of CH. Among patients with preexisting heart disease, treatment with mediastinal radiation therapy plus doxorubicin-based chemotherapy was associated with a 10-year incidence of CH more than 20% higher than treatment with chemotherapy alone. There is a high risk of CH after mediastinal radiation therapy plus doxorubicin-based chemotherapy among patients with preexisting heart disease; this is an important consideration when weighing treatment options, and in the follow-up of these patients.

Cardiac magnetic resonance imaging findings in 20-year survivors of mediastinal radiotherapy for Hodgkin's disease

PURPOSE

The recognition of the true prevalence of cardiac toxicity after mediastinal radiotherapy requires very long follow-up and a precise diagnostic procedure. Cardiac magnetic resonance imaging (MRI) permits excellent quantification of cardiac function and identification of localized myocardial defects and has now been applied to a group of 20-year Hodgkin's disease survivors.

METHODS AND MATERIALS

Of 143 patients treated with anterior mediastinal radiotherapy (cobalt-60, median prescribed dose 40 Gy) for Hodgkin's disease between 1978 and 1985, all 53 survivors were invited for cardiac MRI. Of those, 36 patients (68%) presented for MRI, and in 31 patients (58%) MRI could be performed 20-28 years (median, 24) after radiotherapy. The following sequences were acquired on a 1.5-T MRI: transversal T1-weighted TSE and T2-weighted half-fourier acquisition single-shot turbo-spin-echo sequences, a steady-state free precession (SSFP) cine sequence in the short heart axis and in the four-chamber view, SSFP perfusion sequences under rest and adenosine stress, and a SSFP inversion recovery sequence for late enhancement. The MRI findings were correlated with previously reconstructed doses to cardiac structures.

RESULTS

Clinical characteristics and reconstructed doses were not significantly different between survivors undergoing and not undergoing MRI. Pathologic findings were reduced left ventricular function (ejection fraction <55%) in 7 (23%) patients, hemodynamically relevant valvular dysfunction in 13 (42%), late myocardial enhancement in 9 (29%), and any perfusion deficit in 21 (68%). An association of regional pathologic changes and reconstructed dose to cardiac structures could not be established.

CONCLUSIONS

In 20-year survivors of Hodgkin's disease, cardiac MRI detects pathologic findings in approximately 70% of patients. Cardiac MRI has a potential role in cardiac imaging of Hodgkin's disease patients after mediastinal radiotherapy.

Radiation dose-volume effects in the heart

The literature is reviewed to identify the main clinical and dose-volume predictors for acute and late radiation-induced heart disease. A clear quantitative dose and/or volume dependence for most cardiac toxicity has not yet been shown, primarily because of the scarcity of the data. Several clinical factors, such as age, comorbidities and doxorubicin use, appear to increase the risk of injury. The existing dose-volume data is presented, as well as suggestions for future investigations to better define radiation-induced cardiac injury.

Evaluation of coronary artery disease by computed tomography angiography in patients treated for childhood Hodgkin's lymphoma

PURPOSE To detect pathologies in coronary arteries by computed tomography angiography (CTA) in survivors of childhood Hodgkin's lymphoma who have been treated with radiotherapy and/or cardiotoxic agents. PATIENTS AND METHODS Patients with HL who have been in remission for at least 2 years after completion of therapy were included. CBC, lipid profile, urine analysis, brain natriuretic peptide, troponin-T, creatinine kinase-myocardial band, ECG, telecardiography, echocardiography, and CTA of the patients were performed. Cardiac vascular abnormalities were noted. Results A total of 119 patients were included in the study. In 19 patients (16%), we found coronary artery abnormalities. There was a significant difference between the patients who received mediastinal radiotherapy and those who did not (P = .02). By multivariate analysis, in patients receiving mediastinal radiotherapy the risk of developing a coronary artery abnormality was found to increase 6.8 times compared with patients who did not receive mediastinal radiotherapy (P = .009). Stent implantation was performed in a 28-year-old patient because of critical stenosis in right coronary. In two patients some irregularities were detected both in CTA and conventional angiography, and they remained in close follow-up. A 22-year-old patient whose CTA showed critical stenosis in his left anterior descending artery refused the conventional angiography. CONCLUSION To our knowledge, this is the first large study using CTA for detection of coronary abnormalities in patients treated for HL in pediatric age group. Coronary CTA is a minimally invasive tool for early diagnosis of coronary artery disease in patients who were treated with mediastinal radiotherapy and/or cardiotoxic chemotherapy.

Cardiac outcomes in a cohort of adult survivors of childhood and adolescent cancer: retrospective analysis of the Childhood Cancer Survivor Study cohort

OBJECTIVES

To assess the incidence of and risks for congestive heart failure, myocardial infarction, pericardial disease, and valvular abnormalities among adult survivors of childhood and adolescent cancers.

DESIGN

Retrospective cohort study.

SETTING

26 institutions that participated in the Childhood Cancer Survivor Study.

PARTICIPANTS

14,358 five year survivors of cancer diagnosed under the age of 21 with leukaemia, brain cancer, Hodgkin's lymphoma, non-Hodgkin's lymphoma, kidney cancer, neuroblastoma, soft tissue sarcoma, or bone cancer between 1970 and 1986. Comparison group included 3899 siblings of cancer survivors.

MAIN OUTCOME MEASURES

Participants or their parents (in participants aged less than 18 years) completed a questionnaire collecting information on demographic characteristics, height, weight, health habits, medical conditions, and surgical procedures occurring since diagnosis. The main outcome measures were the incidence of and risk factors for congestive heart failure, myocardial infarction, pericardial disease, and valvular abnormalities in survivors of cancer compared with siblings.

RESULTS

Survivors of cancer were significantly more likely than siblings to report congestive heart failure (hazard ratio (HR) 5.9, 95% confidence interval 3.4 to 9.6; P<0.001), myocardial infarction (HR 5.0, 95% CI 2.3 to 10.4; P<0.001), pericardial disease (HR 6.3, 95% CI 3.3 to 11.9; P<0.001), or valvular abnormalities (HR 4.8, 95% CI 3.0 to 7.6; P<0.001). Exposure to 250 mg/m(2) or more of anthracyclines increased the relative hazard of congestive heart failure, pericardial disease, and valvular abnormalities by two to five times compared with survivors who had not been exposed to anthracyclines. Cardiac radiation exposure of 1500 centigray or more increased the relative hazard of congestive heart failure, myocardial infarction, pericardial disease, and valvular abnormalities by twofold to sixfold compared to non-irradiated survivors. The cumulative incidence of adverse cardiac outcomes in cancer survivors continued to increase up to 30 years after diagnosis.

CONCLUSION

Survivors of childhood and adolescent cancer are at substantial risk for cardiovascular disease. Healthcare professionals must be aware of these risks when caring for this growing population.