Effects of neck radiation therapy on extra-cranial carotid arteries atherosclerosis disease prevalence: systematic review and a meta-analysis

Risk, prevention, screening and management of carotid artery stenosis in head & neck cancer patients-An evidence based review

Our review aims to clarify the incidence of carotid artery stenosis, risks of development, screening, management, and primary prevention strategies documented in the literature after radiation therapy for head and neck cancers. The high prevalence of carotid stenosis after radiation therapy for head and neck cancers has made surveillance and risk stratification critical. In addition to general cardiovascular risk factors such as smoking, diabetes, and dyslipidemia, risk factors for carotid artery stenosis after head and neck radiation included total plaque score, radiotherapy use and dosage, length of time after radiotherapy, and age greater than 50. Cancer subtype, namely nasopharyngeal cancer, may be correlated with increased risk as well, though contrasting results have been found. Interestingly, however, no significant relationship has been found between radiotherapy dose and stroke risk. Surgical management of post-radiation carotid stenosis is similar to that of stenosis unrelated to radiation, with carotid endarterectomy considered to be the gold standard treatment and carotid artery stenting being an acceptable, less-invasive alternative. Medical management of these patients has not been well-studied, but antiplatelet therapy, statins, and blood pressure control may be beneficial. The mainstay of screening for radiation-induced stenosis has been Doppler ultrasound, with measurement of changes in the intima-media thickness being a primary marker of disease development. A literature review was carried out using the MeSH terms "Carotid Artery Stenosis," "Head and Neck Neoplasms," and "Radiotherapy."

Effect of Statins on Patients With Osteoradionecrosis of the Jaw

BACKGROUND

Osteoradionecrosis of the jaw (ORN) is a late complication of radiation therapy. Radiation-induced fibrosis is the most likely mechanism for developing ORN, and statins are effective against radiation-induced fibrosis. However, no reports have indicated the direct effectiveness of statins in treating ORN.

PURPOSE

This study aimed to measure the association between statin exposure and ORN disease resolution.

STUDY DESIGN, SETTING, SAMPLE

This retrospective cohort study included patients with ORN diagnosed between January 2008 and December 2020 at the Hospital's Department of Oral and Maxillofacial Surgery. Patients who were immunocompromised or followed up for < 6 months were excluded.

PREDICTOR VARIABLE

The predictor variable was statin exposure, which was defined as the use of statins for dyslipidemia.

MAIN OUTCOME VARIABLE

The main outcome variable was ORN disease progression status (good prognosis). Patients who showed full recovery and improvement were included in the good prognosis group, and those who showed invariance and deterioration were included in the poor prognosis group.

COVARIATES

We analyzed the clinicodemographic including the age of onset, sex, history of smoking, alcohol consumption, history of chemotherapy, tumor site, association with dental treatment, location (maxilla or mandible), the time to ORN onset from radiation therapy, and stage of ORN, and treatment characteristics including hyperbaric oxygen therapy, long-term macrolide administration, and sequestrectomy.

ANALYSES

We analyzed the association between statin exposure or covariates and time to ORN improvement using bivariate and multivariate Cox regression. The significance level was set at P = .05.

RESULTS

We analyzed 102 patients, and the improvement rate was 32.4%. The favorable prognostic factors were statin exposure (adjusted hazard ratio [HR], 3.71; 95% confidence interval [CI], 1.62 to 8.50; P = .002), onset in the maxilla (HR, 2.15; 95% CI, 1.02 to 4.55; P = .045), and stage 1 of ORN (HR, 2.65; 95% CI, 1.20 to 5.83; P = .016).

CONCLUSION AND RELEVANCE

In this study, statin exposure, onset in the maxilla, and stage 1 of Lyons's classification were favorable prognostic factors for ORN. Although this study's findings were insufficient to recommend statin use for ORN, statins may be a novel and effective treatment for ORN.

Effects of moderate doses of ionizing radiation on experimental abdominal aortic aneurysm

BACKGROUND

Exposure to ionizing radiation has been linked to cardiovascular diseases. However, the impact of moderate doses of radiation on abdominal aortic aneurysm (AAA) remains unknown.

METHODS

Angiotensin II-infused Apoe-/- mice were irradiated (acute, 1 Gray) either 3 days before (Day-3) or 1 day after (Day+1) pomp implantation. Isolated primary aortic vascular smooth muscle cells (VSMCs) were irradiated (acute 1 Gray) for mechanistic studies and functional testing in vitro.

RESULTS

Day-3 and Day+1 irradiation resulted in a significant reduction in aorta dilation (Control: 1.39+/-0.12; Day-3: 1.12+/-0.11; Day+1: 1.15+/-0.08 mm, P<0.001) and AAA incidence (Control: 81.0%; Day-3: 33.3%, Day+1: 53.3%) compared to the non-irradiated group. Day-3 and Day+1 irradiation led to an increase in collagen content in the adventitia (Thickness control: 23.64+/-2.9; Day-3: 54.39+/-15.5; Day+1 37.55+/-10.8 mm, P = 0.006). However, the underlying protective mechanisms were different between Day-3 and Day+1 groups. Irradiation before Angiotensin II (AngII) infusion mainly modulated vascular smooth muscle cell (VSMC) phenotype with a decrease in contractile profile and enhanced proliferative and migratory activity. Irradiation after AngII infusion led to an increase in macrophage content with a local anti-inflammatory phenotype characterized by the upregulation of M2-like gene and IL-10 expression.

CONCLUSION

Moderate doses of ionizing radiation mitigate AAA either through VSCM phenotype or inflammation modulation, depending on the time of irradiation.

Cancer Therapy and Exercise Intolerance: The Heart Is But a Part: JACC: CardioOncology State-of-the-Art Review

The landscape of cancer therapeutics is continually evolving, with successes in improved survivorship and reduced disease progression for many patients with cancer. Improved cancer outcomes expose competing comorbidities, some of which may be exacerbated by cancer therapies. The leading cause of disability and death for many early-stage cancers is cardiovascular disease (CVD), which is often attributed to direct or indirect cardiac injury from cancer therapy. In this review, the authors propose that toxicities related to conventional and novel cancer therapeutics should be considered beyond the heart. The authors provide a framework using the oxygen pathway to understand the impact of cancer treatment on peak oxygen uptake, a marker of integrative cardiopulmonary function and CVD risk. Peripheral toxicities and the impact on oxygen transport are discussed. Consideration for the broad effects of cancer therapies will improve the prediction and identification of cancer survivors at risk for CVD, functional disability, and premature mortality and those who would benefit from therapeutic intervention, ultimately improving patient outcomes.

Comparison of Risks of Late Effects From Radiation Therapy in Children Versus Adults: Insights From the QUANTEC, HyTEC, and PENTEC Efforts

Pediatric Normal Tissue Effects in the Clinic (PENTEC) seeks to refine quantitative radiation dose-volume relationships for normal-tissue complication probabilities (NTCPs) in survivors of pediatric cancer. This article summarizes the evolution of PENTEC and compares it with similar adult-focused efforts (eg, Quantitative Analysis of Normal Tissue Effects in the Clinic [QUANTEC] and Hypofractionated Treatment Effects in the Clinic [HyTEC]) with respect to content, oversight, support, scope, and methodology of literature review. It then summarizes key organ-specific findings from PENTEC in an attempt to compare NTCP estimates in children versus adults. In brief, select normal-tissue risks within developing organs and tissues (eg, maldevelopment of musculoskeletal tissue, teeth, breasts, and reproductive organs) are primarily relevant only in children. For some organs and tissues, children appear to have similar (eg, brain for necrosis, optic apparatus, parotid gland, liver), greater (eg, brain for neurocognition, cerebrovascular, breast for lactation), less (ovary), or perhaps slightly less (eg, lung) risks of toxicity versus adults. Similarly, even within the broad pediatric age range (including adolescence), for some endpoints, younger children have greater (eg, hearing and brain for neurocognition) or lesser (eg, ovary, thyroid) risks of radiation-associated toxicities. NTCP comparisons in adults versus children are often confounded by marked differences in treatment paradigms that expose normal tissues to radiation (ie, cancer types, prescribed radiation therapy dose and fields, and chemotherapy agents used). To add to the complexity, it is unclear if age is best analyzed as a continuous variable versus with age groupings (eg, infants, young children, adolescents, young adults, middle-aged adults, older adults). Further work is needed to better understand the complex manner in which age and developmental status affect risk.

Low to moderate dose 137Cs (γ) radiation promotes M2 type macrophage skewing and reduces atherosclerotic plaque CD68+ cell content in ApoE(-/-) mice

The effects of low doses of ionizing radiation on atherosclerosis remain uncertain, particularly as regards the generation of pro- or anti-inflammatory responses, and the time scale at which such effects can occur following irradiation. To explore these phenomena, we exposed atheroprone ApoE(-/-) mice to a single dose of 0, 0.05, 0.5 or 1 Gy of 137Cs (γ) administered at a 10.35 mGy min-1 dose rate and evaluated short-term (1-10 days) and long-term consequences (100 days). Bone marrow-derived macrophages were derived from mice 1 day after exposure. Irradiation was associated with a significant skewing of M0 and M2 polarized macrophages towards the M2 phenotype, as demonstrated by an increased mRNA expression of Retnla, Arg1, and Chil3 in cells from mice exposed to 0.5 or 1 Gy compared with non-irradiated animals. Minimal effects were noted in M1 cells or M1 marker mRNA. Concurrently, we observed a reduced secretion of IL-1β but enhanced IL-10 release from M0 and M2 macrophages. Effects of irradiation on circulating monocytes were most marked at day 10 post-exposure, when the 1 Gy dose was associated with enhanced numbers of both Ly6CHigh and Ly6Low cells. By day 100, levels of circulating monocytes in irradiated and non-irradiated mice were equivalent, but anti-inflammatory Ly6CLow monocytes were significantly increased in the spleen of mice exposed to 0.05 or 1 Gy. Long term exposures did not affect atherosclerotic plaque size or lipid content, as determined by Oil red O staining, whatever the dose applied. Similarly, irradiation did not affect atherosclerotic plaque collagen or smooth muscle cell content. However, we found that lesion CD68+ cell content tended to decrease with rising doses of radioactivity exposure, culminating in a significant reduction of plaque macrophage content at 1 Gy. Taken together, our results show that short- and long-term exposures to low to moderate doses of ionizing radiation drive an anti-inflammatory response, skewing bone marrow-derived macrophages towards an IL-10-secreting M2 phenotype and decreasing plaque macrophage content. These results suggest a low-grade athero-protective effect of low and moderate doses of ionizing radiation.

Review of Cerebral Radiotherapy-Induced Vasculopathy in Pediatric and Adult Patients

Radiation therapy (RT) causes radiation-induced vasculopathy, which requires clinicians to identify and manage this side effect in pediatric and adult patients. This article reviews previous findings about the pathophysiology of RT-induced vascular injury, including endothelial cell injury, oxidative stress, inflammatory cytokines, angiogenic pathways, and remodeling. The vasculopathy is categorized into ischemic vasculopathy, hemorrhagic vasculopathy, carotid artery injury, and other malformations (cavernous malformations and aneurysms) in populations of pediatric and adult patients separately. The prevention and management of this RT-induced side effect are also discussed. The article summarizes the distribution and risk factors of different types of RT-induced vasculopathy. This will help clinicians identify high-risk patients with corresponding vasculopathy subtypes to deduce prevention and treatment strategies accordingly.

Mechanisms by which statins protect endothelial cells from radiation-induced injury in the carotid artery

Background

The incidental use of statins during radiation therapy has been associated with a reduced long-term risk of developing atherosclerotic cardiovascular disease. However, the mechanisms by which statins protect the vasculature from irradiation injury remain poorly understood.

Objectives

Identify the mechanisms by which the hydrophilic and lipophilic statins pravastatin and atorvastatin preserve endothelial function after irradiation.

Methods

Cultured human coronary and umbilical vein endothelial cells irradiated with 4 Gy and mice subjected to 12 Gy head-and-neck irradiation were pretreated with statins and tested for endothelial dysfunction, nitric oxide production, oxidative stress, and various mitochondrial phenotypes at 24 and 240 h after irradiation.

Results

Both pravastatin (hydrophilic) and atorvastatin (lipophilic) were sufficient to prevent the loss of endothelium-dependent relaxation of arteries after head-and-neck irradiation, preserve the production of nitric oxide by endothelial cells, and suppress the cytosolic reactive oxidative stress associated with irradiation. However, only pravastatin inhibited irradiation-induced production of mitochondrial superoxide; damage to the mitochondrial DNA; loss of electron transport chain activity; and expression of inflammatory markers.

Conclusions

Our findings reveal some mechanistic underpinnings of the vasoprotective effects of statins after irradiation. Whereas both pravastatin and atorvastatin can shield from endothelial dysfunction after irradiation, pravastatin additionally suppresses mitochondrial injury and inflammatory responses involving mitochondria. Clinical follow-up studies will be necessary to determine whether hydrophilic statins are more effective than their lipophilic counterparts in reducing the risk of cardiovascular disease in patients undergoing radiation therapy.

An Analysis of Volume, Length and Segmentation of Free Fibula Flap in Reconstruction of the Jaws: Investigation of Their Role on Flap Failure

Reconstruction of defects of the jaws is mainly performed via free fibula flap. An incidence of 2–21% of overall flap failure is still described. We investigated the roles of volume, length and number of fibula flap segments on flap survival using novel three-dimensional segmentation tools. We also analyzed the role of other possible risk factors. Seventy-one consecutive patients with a follow up of at least three months and who underwent free fibula flap reconstruction in a single center between 2002 and 2022 have been evaluated. A total of 166 fibula segments were analyzed. Malignancies were the main reason of resection (45.1%). In 69% of the cases a reconstruction of the mandible was performed. The flaps were mainly divided in two segments (39%) (range 1–4), with a mean length of 2.52 cm and a mean volume was 3.37 cm3. Total flap failure (TFF) occurred in 12 cases, (16.9%), while partial flap failure (PFF) appeared in 3 patients (4.2%). Volume, length and number of fibula flap segments did not seem to influence flap failure incidence in uni- and multivariate analysis. Reconstruction of the maxilla and use of a recipient vessel different from the facial artery seemed to significantly impact on flap failure. Smoking and previous surgeries showed a higher trend to flap failure, but they did not reach statistical significance. Prospective and multicentric analysis on a wider population should be assessed.

When Two Maladies Meet: Disease Burden and Pathophysiology of Stroke in Cancer

Stroke and cancer are disabling diseases with an enormous global burden, disproportionately affecting vulnerable populations and low- and middle-income countries. Both these diseases share common risk factors, which warrant concerted attention toward reshaping population health approaches and the conducting of fundamental studies. In this article, an overview of epidemiological trends in the prevalence and burden of cancer and stroke, underlying biological mechanisms and clinical risk factors, and various tools available for risk prediction and prognosis are provided. Finally, future recommendations for research and existing gaps in our understanding of pathophysiology. Further research must investigate the causes that predispose patients to an increased risk of stroke and/or cancer, as well as biomarkers that can be used to predict growing morbidity and mortality.

Cancer and stroke: What do we know and where do we go?

Cancer is an increasingly recognized cause for ischemic stroke, with recent acknowledgement of cancer-related stroke as an emerging stroke subtype with unique pathophysiologic mechanisms. In addition, cancer-related stroke may differ from stroke in the general population as cancer patients may not receive guideline-recommended stroke care, and the occurrence of stroke may also preclude patients from receiving optimal cancer treatments. Due to the high degree of morbidity and mortality associated with both conditions, understanding the relationship between stroke and cancer is crucial. In this narrative review, we discuss the association between cancer and stroke, the unique pathophysiologic mechanisms underlying this phenomenon, treatment options including acute reperfusion therapies and secondary prevention strategies, compare outcomes between cancer-related stroke and stroke in the general population, and review new and emerging evidence in this field.

The Prediction of Cardiac Events Using Contemporary Risk Prediction Models after Radiation Therapy for Head and Neck Cancer

This study aims to evaluate the efficacy of the Pooled Cohort Equation (PCE), U.S. Preventative Services Task Force (USPSTF), and Framingham Risk Score (FRS) models in predicting ASCVD events among patients receiving radiation therapy (RT) for head and neck cancer (HNCA). From a large cohort of HNCA patients treated with RT, ASCVD events were adjudicated. Observed vs. predicted ASCVD events were compared. We compared rates by statin eligibility status. Regression models and survival analysis were used to identify the relationship between predicted risk and post-RT outcomes. Among the 723 identified patients, 274 (38%) were statin-eligible based on USPSTF criteria, 359 (49%) based on PCE, and 234 (32%) based on FRS. During follow-up, 17% developed an ASCVD, with an event rate of 27 per 1000 person-years, 68% higher than predicted (RR 1.68 (95% CI: 1.02, 2.12), p < 0.001). In multivariable regression, there was no difference in event rates by statin eligibility status (p > 0.05). Post-RT, the observed event rate was higher than the predicted ASCVD risk across all grades of predicted risk (p < 0.05) and the observed risk of an ASCVD event was high even among patients predicted to have a low risk of ASCVD. In conclusion, current ASCVD risk calculators significantly underestimate the risk for ASCVD among patients receiving RT for HNCA.

Risk of CVD Following Radiotherapy for Head and Neck Cancer: An Updated Systematic Review and Meta-Analysis

Background

The relative risk for cerebrovascular disease (CVD) is increased in patients with head and neck cancer (HNC) treated with radiotherapy (RT). However, the current relative risk for CVD following RT has not been well clarified. The purpose of this study was to analyze the effect of RT and update the risk of CVD following RT in HNC patients through a systematic review and meta-analysis.

Material and Methods

We conducted an online database search and systematic review of observational studies that reported on CVD and extracranial carotid stenosis in patients with HNC who had undergone RT. Articles published in Medline and PubMed from 1980 to 2021 were identified and collected.

Results

Of the forty-seven articles identified from PubMed and forty-four articles identified from 3 systematic reviews, twenty-two studies were included. We found that neck RT was a significant risk factor for CVD (HR 3.97, 95% CI: 2.89-5.45). Patients with HNC treated by RT had an increased OR (7.36, 95% CI: 4.13-13.11) for CVD, and approximately 26% (95% CI: 22%-31%) of HNC patients treated with RT were at risk for CVD with more than 50% reduction in carotid diameter.

Conclusion

The risk of CVD is increased in patients with HNC treated by RT, and recent improvements in RT techniques may have contributed to the decreased risk of CVD. These results suggest that regular follow-up and appropriate screening for CVD should be required for patients with HNC.

Outcomes of carotid artery stenting in patients with radiation arteritis compared with those with atherosclerotic disease

OBJECTIVE

Head and neck malignancies are often treated with radiotherapy (RT). Nearly 80% of patients who have undergone RT will develop carotid radiation arteritis to some degree and 29% will develop stenosis >50%. Surgery in a radiated neck has higher rates of complications, and carotid artery stenting (CAS) has become the primary therapy. The outcomes for CAS in patients with radiation arteritis have not been rigorously evaluated. The objective of the present study was to evaluate the differences in perioperative outcomes, restenosis rates, the need for reintervention, and freedom from mortality between RT patients and patients with atherosclerotic disease who had undergone CAS.

METHODS

The national Vascular Quality Initiative CAS dataset from 2016 to 2019 comprised the sample for analyses (n = 7343). The primary independent variable was previous head and/or neck RT. The primary endpoint was the interval to mortality. The secondary endpoints were the cumulative incidence of restenosis (>50% and >70% by duplex ultrasound) and reintervention. We also examined the following secondary perioperative endpoints: myocardial infarction, in-hospital mortality (death before discharge), neurologic events, ipsilateral stroke, and contralateral stroke. Kaplan-Meier and multivariable Cox proportional hazard models were used to assess for mortality, and cumulative incidence function estimates were used for the nonfatal endpoints.

RESULTS

Of the 7218 patients, 1199 (17%) had undergone prior RT. We found a significant difference in the 3-year estimates of mortality for those with and without prior RT (9.4% and 7.5%, respectively; P = .03). Furthermore, on adjusted analysis, we observed a 58% increase in the risk of mortality for those with prior RT (adjusted hazard ratio, 1.58; 95% confidence interval, 1.13-2.21). We did not observe any differences in the risk of perioperative complications (myocardial infarction, in-hospital mortality, ipsilateral or contralateral stroke), restenosis (>50% or >70%), or reintervention for the prior RT group compared with those without RT.

CONCLUSIONS

The CAS patients with RT had significantly greater mortality at all time points compared with those without RT, even after adjusting for other covariates. No significant difference was found in the incidence of perioperative complications, reintervention, or restenosis between the two groups. The present study is unique because of the large sample size and length of follow-up. The results suggest that for this high-risk group, CAS provides the same patency as it does for atherosclerotic carotid stenosis and avoids potentially morbid cranial nerve injury and wound healing complications.

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.

Prevalence of carotid plaque stenosis after head and neck radiotherapy – an observational study of 156 survivors

Summary: Background: Radiotherapy for head and neck cancer (HNC) represents a well-known predisposing factor for asymptomatic carotid artery lesions and acute cerebrovascular accidents. Our aim is to provide contemporary estimates on the prevalence, severity, and characteristics of carotid artery lesions in HNC survivors. Patients and methods: We prospectively included HNC patients who underwent radiotherapy and were free from the disease at the time of duplex ultrasound evaluation. Patients were re-contacted telephonically and those who agreed to participate were invited for an ambulatory visit when the investigators collected clinical information and performed duplex ultrasound examination based on a predefined protocol. Results: A total of 156 patients were included and underwent duplex ultrasound examination after a mean of 65.2 months from the last session of radiotherapy. A total of 36 patients (23.1%) had normal carotid arteries; mild, non-stenotic lesions were observed in 49.4% (n = 77) of patients; severe stenotic plaques were found in 27.5% (n = 43) of patients. One patient found with an asymptomatic occlusion of the left ICA. The prevalence of major cardiovascular risk factors and high radiation dose increased proportionally with plaque severity. Low echogenicity plaque was found in 59 (37.8%) patients on the right side and 57 (36.5%) on the left side; long segment plaque in 49 (31.4%) patients on the right side and in 47 (30.1%) on the left side; an atypical location of the lesions in 42 (26.9%) patients on the right side and in 48 (30.8%) on the left side. Conclusions: The prevalence of occlusion and severe stenosis after radiotherapy for HNC was very low in our study population. Low echogenicity plaque, long segment plaque, and an atypical location were common findings. Classic cardiovascular risk factors appear to have had a causative role: a routine screening of radiotherapy-treated patients might be necessary only in patients with concomitant cardiovascular risk factors or exposed to high-dose neck radiation.

Screening for irradiation vasculopathy by intima-media thickness sonography in head and neck cancer patients

Purpose

Post-irradiation vasculopathy is a severe form of atherosclerosis and affects the prognosis of head and neck cancer survivors. Sonographic intima-media thickness (IMT) precedes stenosis, plaque formation, and cerebrovascular events. Therefore, IMT may be a valuable screening marker for post-irradiation toxicity. However, the critical irradiation dose and the onset of IMT increase remain unclear.

Methods

The cross-sectional study analysed the carotid artery IMT in 96 irradiated patients and 41 controls regarding irradiation dose, post-irradiation-interval, and cardiovascular risk factors. Distinct irradiation doses to the tumour side and the contralateral hemineck enabled detection of dose depended effects within one patient and control of risk factors.

Results

Radiotherapy caused a dose-dependent increase in IMT. The toxicity did not have saturation effects for > 60 Gy. The IMT increase occurred in short-term following radiotherapy and the risk for a pathological value (> 0.9 mm) rose significantly. The correlation between IMT and radiotherapy was comparable to established cardiovascular risk factors.

Conclusion

Radiotherapists should consider the additional toxicity of high doses for non-metastatic head and neck cancer. If neck metastases require radiotherapy with boost, IMT measurement is suitable for early detection of carotid artery damage.

Imaging of the post-treatment neck

Post-treatment imaging of the neck is complex. It is important to have an understanding of the expected treatment related appearances as well as the possible complications. Common findings after radiation therapy include generalised soft-tissue oedema and thickening of the skin and platysma muscle. There are a number of complications of radiation that may be seen on imaging, including osteoradionecrosis, chondronecrosis, and accelerated atherosclerosis. Surgical procedures are variable depending on the primary tumour site and extent. The use of flap reconstructions can further complicate the imaging appearances. Any new nodule of enhancement or bone/cartilage erosion should raise concern for tumour recurrence. It is also important to assess for nodal recurrence. A standardised approach to reporting may help to increase accuracy and guide treatment decisions.

Longitudinal atherosclerotic changes after radio(chemo)therapy of hypopharyngeal carcinoma

Background

Radiotherapy treatment of head and neck cancer affects local arteries and increases the risk of stroke. This study aimed at a closer characterization of this damage and its development in time with a longitudinal study set up.

Methods

Male patients treated between 2011 and 2016 for hypopharyngeal carcinoma were identified from the in-house clinical data base. They were included into the study if besides the planning CT at least one additional CT image was available from follow-up (13 patients) or at least two MRI scans (16 patients of which 2 were already included). All patients received radiotherapy, and chemotherapy was administered to 16 patients. The time from the beginning of radiotherapy to the last available image ranged from 2 months to 4.5 years.

For six segments of the carotid arteries, the number and volume of atherosclerotic plaques were determined from the CT scans, and the intima media thickness from the MRI scans. Information on comorbid cardiovascular disease, hypertension and diabetes mellitus was retrieved from medical records.

Results

Total plaque volume rose from 0.25 cm³ before to 0.33 cm³ after therapy but this was not significant (p = 0.26). The mean number of plaques increased from 5.7 to 8.1 (p = 0.002), and the intima media thickened from 1.17 mm to 1.35 mm (p = 0.002). However, the mean intima media thickness practically did not change in patients with comorbid diabetes mellitus (p-value for homogeneity: 0.03). For patients without diabetes mellitus, dynamics of both plaque number and intima media thickness, was consistent with an increase until about one year after therapy and no further progression thereafter.

Conclusion

Our study confirmed the thickening of artery walls and the increase in the number of plaques. Results imply that definitive radiation damage to the artery walls can be determined not earlier than about one year after radiotherapy and there is no substantial deterioration thereafter. Reasons for the absence of an observable intima media thickening in patients with diabetes are unclear.

Wound monitoring of pH and oxygen in patients after radiation therapy

OBJECTIVES

Postradiogenic wound healing disorders are an important clinical problem. While a variety of treatment modalities are available, there is no strategy to objectively judge treatment success. The aim of this study was to evaluate a 2D luminescence imaging system for pH and oxygen in non-healing wounds after radiotherapy.

METHODS

Luminescence 2D imaging was performed with the VisiSens (Presens, Regensburg, Germany) 2D imaging systems A1 and A2 for oxygen and pH, respectively. Biocompatible planar luminescent sensor foils were applied to non-irradiated and irradiated skin as well as to radiogenic wounds of five patients and the pH and the oxygen saturation was determined.

RESULTS

pH measurements showed significant differences between non-irradiated skin (6.46 ± 0.18) and irradiated skin (6.96 ± 0.26). Radiogenic wounds exhibited the highest pH values (7.53 ± 0.26). Oxygen measurements revealed a mean oxygen saturation of non-irradiated skin of 6.19 ± 0.83 mmHg. The highest value of oxygen saturation (28.4 ± 2.4 mmHg) was found on irradiated skin while irradiated wounds had a poor oxygen saturation (9.4 ± 2.2 mmHg) (mean ± s.e.m.).

CONCLUSION

We found that routine measurement of pH and pO2 in patients could be easily integrated into the clinical routine. The results of the measurements show unfavorable pH and oxygen saturation conditions for wound healing in irradiated wounds. Interestingly, irradiated wounds exhibit a more pronounced hypoxia than irradiated skin which is reflected by an altered pH and pO2 compared to unirradiated skin, which has the potential to serve as a prognostic marker in the future. In addition to the objectification of the treatment success of postradiogenic wound healing disorders, the extent of skin toxicity could already be predicted during radiotherapy with this method.

Late delayed radiation-induced cerebral Arteriopathy by high-resolution magnetic resonance imaging: a case report

Background

Radiation therapy can cause cerebral arteriopahty, resulting in ischemic stroke. We document late-delayed cerebral arteriopathy by high-resolution magnetic resonance imaging (HR-MRI) in a middle aged man who had cranial irradiation 19 years earlier.

Case presentation

A 45-year-old man was diagnosed with frontal lobe glioma 19 years ago and was treated with radiation after surgical resection. He was admitted to our hospital with an acute cerebral infarction in November 8, 2017. Traditional MRI examination and HR-MRI (sagittal, reconstruction of coronal and axial) were performed at admission. He was treated with prednisone (30 mg/day) and clinical symptoms disappeared after 3 months by telephone follow-up. Our patient complained of dizziness and blurred vision and traditional MRI examination indicated acute ischemic stroke in temporal lobe and occipital lobe and microbleeds. In order to define the exact mechanism of stroke, blood tests, auto-immune screening and thrombophilia were performed and results were normal. Electrocardiography and echocardiography were negative and cardiogenic cerebral embolism was excluded. In cerebrospinal fluid (CSF) examination, level of albumin and IgG were elevated. HR-MRI showed vessel wall thickening in T1-weighted imaging, narrow lumen in proton density imaging and vessel wall concentric enhancement in contrast-enhanced T1- weighted imaging. Combined with radiotherapy history, the patient was diagnosed with radioactive vasculitis.

Conclusion

Radiation-induced cerebrovascular damages could be a lasting progress, which we cannot ignore. HR-MRI can provide sensitive and accurate diagnostic assessment of radiation-induced arteritis and may be a useful tool for the screening of causes of cryptogenic stroke.

Sequelae and management of radiation vasculopathy in neurosurgical patients

The term "radiation vasculopathy" defines a heterogeneous and poorly defined complex of vessel injury due to radiation. Radiation vasculopathy remains underrecognized and poorly treated with respect to head and neck radiotherapy. Distinct injury patterns to small (≤ 100-μm), medium (> 100-μm), and large (> 500-μm) vessels can occur, resulting in carotid stenosis, intracranial stenosis, and vascular anomalies (e.g., cavernous malformations, aneurysms). Because of the lack of clinical evidence and guidelines, treatment plans involve medical management, carotid endarterectomy, and carotid artery stenting and are developed on a patient-by-patient basis. In this review, the authors discuss the current pathophysiology, imaging, clinical impact, and potential treatment strategies of radiation vasculopathy with clinical pertinence to practicing neurosurgeons and neurologists. A review of 4 patients with prior head and neck tumors in whom delayed radiation vasculopathy developed after radiotherapy demonstrates the application of various treatment options in a case-by-case manner. Earlier recognition of radiation vasculopathy disease patterns may enable earlier initiation of treatment and monitoring for complications. Standardized terminology and treatments may assist with improving clinical outcomes.

miR-29b Mediates the Chronic Inflammatory Response in Radiotherapy-Induced Vascular Disease

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Radiotherapy is a powerful treatment strategy in patients with oncological diseases.

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Radiation-induced vasculopathy can dose dependently increase the risk of ischemic cardiovascular diseases (e.g., myocardial infarction, heart failure, stroke).

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The microRNA miR-29b is repressed in radiation-induced vasculopathy (human irradiated vs. nonirradiated tissue specimen, as well as in murine and cell culture models of irradiation).

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Pentraxin-3 and dipeptidyl-peptidase 4 are the main downstream effectors of miR-29b in radiation-induced vasculopathy.

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miR-29b mimics were able to limit pentraxin-3 and dipeptidyl-peptidase 4 levels in the irradiated vasculature (murine model) and to constrain the burden of vascular inflammation.

As a consequence of the success of present-day cancer treatment, radiotherapy-induced vascular disease is emerging. This disease is caused by chronic inflammatory activation and is likely orchestrated in part by microRNAs. In irradiated versus nonirradiated conduit arteries from patients receiving microvascular free tissue transfer reconstructions, irradiation resulted in down-regulation of miR-29b and up-regulation of miR-146b. miR-29b affected inflammation and adverse wound healing through its targets pentraxin-3 and dipeptidyl-peptidase 4. In vitro and in vivo, we showed that miR-29b overexpression therapy, through inhibition of pentraxin-3 and dipeptidyl-peptidase 4, could dampen the vascular inflammatory response.

Cerebrovascular Insufficiency from Radiation-Induced Progressive Obstruction of Supra-Aortic Vessels

BACKGROUND

Radiation therapy may accelerate atherosclerosis with progressive stenosis and occlusions of supra-aortic trunks.

METHODS AND RESULTS

We report the case of a 44-year-old woman with radiation-induced occlusion of the supra-aortic trunks presenting with recurrent cerebrovascular insufficiency after an unusual surgical revascularization technique (retrograde femoral-axillary bypass) performed for late failure of previous endovascular treatment.

CONCLUSIONS

Customized surgical procedure can be considered as a bailout to improve cerebral blood inflow in selected cases.

Arterial events in cancer patients-the case of acute coronary thrombosis

Patients with cancer are at high risk for both venous and arterial thrombotic complications. A variety of factors account for the greater thrombotic risk, including the underlying malignancy and numerous cancer-directed therapies. The occurrence of an acute thrombotic event in patients with cancer is associated with substantial morbidity and mortality. Acute coronary syndrome (ACS) represents a particularly important cardiovascular complication in cancer patients. With cardio-vascular risk factors becoming more prevalent in an aging cancer population that is surviving longer, questions pertaining to the appropriate management of vascular toxicity are likely to assume even greater value in the coming years. In this article, we review the current understanding of ACS in patients with cancer. The predisposition to thrombosis in a malignant host and the cancer treatments most commonly associated with vascular toxicity are reviewed. Risk prediction and management strategies are discussed, and discrepancies in the clinical evidence are highlighted.

Peripheral Non-atherosclerotic Arterial Disorders: What Radiologists Need to Know

Peripheral non-atherosclerotic arterial disorders (NAADs) are a heterogeneous group of rather uncommon conditions that tend to manifest in subjects without atherosclerosis. Each of these conditions has distinctive pathophysiology; however, there are some common clinical and radiological characteristics and in some cases a common treatment approach that unifies these conditions to a specific group, hence the NAADs. Clinicians and radiologists often fail to recognize NAADs, and there might be a delay in the management of such patients; this may result in seriously adverse outcomes that could otherwise have been avoided or minimized. Knowledge of these conditions and of their radiological appearances is therefore important to help establish a correct diagnosis to allow the prompt initiation of treatment. The purpose of this pictorial review is to present a selection of NAADs cases and to discuss the radiological characteristics and the most common lines of therapeutic approaches.

Risk of Cerebrovascular Events in 178 962 Five-Year Survivors of Cancer Diagnosed at 15 to 39 Years of Age: The TYACSS (Teenage and Young Adult Cancer Survivor Study)

BACKGROUND

Survivors of teenage and young adult cancer are at risk of cerebrovascular events, but the magnitude of and extent to which this risk varies by cancer type, decade of diagnosis, age at diagnosis, and attained age remains uncertain. This is the largest-ever cohort study to evaluate the risks of hospitalization for a cerebrovascular event among long-term survivors of teenage and young adult cancer.

METHODS

The population-based TYACSS (Teenage and Young Adult Cancer Survivor Study) (N=178,962) was linked to Hospital Episode Statistics data for England to investigate the risks of hospitalization for a cerebrovascular event among 5-year survivors of cancer diagnosed when 15 to 39 years of age. Observed numbers of first hospitalizations for cerebrovascular events were compared with that expected from the general population using standardized hospitalization ratios (SHRs) and absolute excess risks per 10 000 person-years. Cumulative incidence was calculated with death considered a competing risk.

RESULTS

Overall, 2782 cancer survivors were hospitalized for a cerebrovascular event-40% higher than expected (SHR=1.4, 95% confidence interval, 1.3-1.4). Survivors of central nervous system (CNS) tumors (SHR=4.6, 95% confidence interval, 4.3-5.0), head and neck tumors (SHR=2.6, 95% confidence interval, 2.2-3.1), and leukemia (SHR=2.5, 95% confidence interval, 1.9-3.1) were at greatest risk. Males had significantly higher absolute excess risks than females (absolute excess risks =7 versus 3), especially among head and neck tumor survivors (absolute excess risks =30 versus 11). By 60 years of age, 9%, 6%, and 5% of CNS tumor, head and neck tumor, and leukemia survivors, respectively, had been hospitalized for a cerebrovascular event. Beyond 60 years of age, every year, 0.4% of CNS tumor survivors were hospitalized for a cerebral infarction (versus 0.1% expected), whereas at any age, every year, 0.2% of head and neck tumor survivors were hospitalized for a cerebral infarction (versus 0.06% expected).

CONCLUSIONS

Survivors of a CNS tumor, head and neck tumor, and leukemia are particularly at risk of hospitalization for a cerebrovascular event. The excess risk of cerebral infarction among CNS tumor survivors increases with attained age. For head and neck tumor survivors, this excess risk remains high across all ages. These groups of survivors, particularly males, should be considered for surveillance of cerebrovascular risk factors and potential pharmacological interventions for cerebral infarction prevention.

Calcified carotid artery atheromas on panoramic radiographs of head and neck cancer patients before and after radiotherapy

Background

The aims of this study were to verify if head and neck radiotherapy (RT) is able to induce calcified carotid artery atheroma (CCAA) in a large head and neck cancer (HNC) population and also to compare the socio-demographic and clinical findings of patients with and without CCAA detected on panoramic radiographs.

Material and Methods

Panoramic radiographs taken before and after head and neck radiotherapy (RT) of 180 HNC patients were selected and analyzed in order to identify the presence of CCAA. In addition, CCAA presence or absence on panoramic radiographs were compared and correlated with clinicopathological findings.

Results

A high overall prevalence of CCAA was found on panoramic radiographs (63 out of 180 = 35%) of HNC patients. No significant difference of CCAA before and after RT was observed. There were also no differences between groups (with and without CCAA) regarding age, gender, tobacco and alcohol use, arterial hypertension, diabetes mellitus, acute myocardial infarction, hypercholesterolemia, tumor location, clinical stage of disease and RT dose. However, there was a greater prevalence of strokes in patients with CCAA (p<0.05).

Conclusions

Although CCAA were frequently found in panoramic radiographs of patients with HNC, RT seems not to alter the prevalence of these calcifications.

Key words:Head and neck cancer, radiotherapy, carotid artery diseases, panoramic radiography.

Head and Neck Cancer Survivorship Care Guideline: American Society of Clinical Oncology Clinical Practice Guideline Endorsement of the American Cancer Society Guideline

Purpose This guideline provides recommendations on the management of adults after head and neck cancer (HNC) treatment, focusing on surveillance and screening for recurrence or second primary cancers, assessment and management of long-term and late effects, health promotion, care coordination, and practice implications. Methods ASCO has a policy and set of procedures for endorsing clinical practice guidelines that have been developed by other professional organizations. The American Cancer Society (ACS) HNC Survivorship Care Guideline was reviewed for developmental rigor by methodologists. An ASCO Expert Panel reviewed the content and recommendations, offering modifications and/or qualifying statements when deemed necessary. Results The ASCO Expert Panel determined that the ACS HNC Survivorship Care Guideline, published in 2016, is clear, thorough, clinically practical, and helpful, despite the limited availability of high-quality evidence to support many of the recommendations. ASCO endorsed the ACS HNC Survivorship Care Guideline, adding qualifying statements aimed at promoting team-based, multispecialty, multidisciplinary, collaborative head and neck survivorship care. Recommendations The ASCO Expert Panel emphasized that caring for HNC survivors requires a team-based approach that includes primary care clinicians, oncology specialists, otolaryngologists, dentists, and other allied professionals. The HNC treatment team should educate the primary care clinicians and patients about the type(s) of treatment received, the likelihood of potential recurrence, and the potential late and long-term complications. Primary care clinicians should recognize symptoms of recurrence and coordinate a prompt evaluation. They should also be prepared to manage late effects either directly or by referral to appropriate specialists. Health promotion is critical, particularly regarding tobacco cessation and dental care. Additional information is available at www.asco.org/HNC-Survivorship-endorsement and www.asco.org/guidelineswiki .

Perioperative stroke in a patient undergoing surgery for oral cancer: A case report

Carotid artery stenosis is a significant risk factor for stroke. In elderly patients with carotid atherosclerosis and stenosis, it is not unusual for oral, head and neck cancer surgery to be performed. The present study describes a case of stroke that occurred during a neck dissection for the treatment of cervical lymph node metastasis of a left maxillary gingival carcinoma. The patient was an 84-year-old female who was considered to be at high risk of a stroke based on pre-operative head and neck computed tomography scans, which detected severe carotid atherosclerosis and stenosis. There was no possible stroke prophylaxis available during the performance of the neck dissection in the present case. However, if patients are evaluated to be high-risk pre-operatively, statin agents should be administered, the surgery should be carefully performed, adequate sedation should be maintained post-operatively and the patient should be followed up, aiming to achieve the early detection of a possible stroke.

Cardiovascular Complications of Cranial and Neck Radiation

OPINION STATEMENT

Cancer survivors who receive head and neck radiation are at increased risk for cerebrovascular events. This is mediated via damage to the hypothalamus-pituitary axis leading to the metabolic syndrome and extracranial arterial injury leading to carotid artery stenosis. Head and neck radiation can also lead to intracranial injury that can present as moyamoya, especially in children. Survivors require lifelong periodic follow-up for the development of pan-hypopituitarism or its individual components as well as for dyslipidemia and obesity. Aggressive control of traditional cardiovascular risk factors is recommended to reduce cardiovascular morbidity and mortality. There are no specific guidelines for the surveillance and management of asymptomatic carotid artery disease in cancer survivors. However, regular detailed examination for carotid bruits and neurological symptoms is recommended. Treatment of significant radiation-induced carotid artery disease has not been specifically studied and is based upon recommendations for patients with atherosclerotic carotid stenosis. Carotid endarterectomy can be difficult in radiation patients due to anatomic concerns and the risk of post-operative cranial nerve injury and wound complications but should be considered in patients with suitable anatomy and neck architecture. Carotid artery stenting, while successful, may be associated with greater long-term mortality and neurologic complications. Regardless of the strategy employed, radiation patients are at increased risk for restenosis and should undergo routine surveillance even after revascularization.

Chronic Internal Exposure to Low Dose 137Cs Induces Positive Impact on the Stability of Atherosclerotic Plaques by Reducing Inflammation in ApoE-/- Mice

After Chernobyl and Fukushima Daï Chi, two major nuclear accidents, large amounts of radionuclides were released in the environment, mostly caesium 137 (137Cs). Populations living in contaminated territories are chronically exposed to radionuclides by ingestion of contaminated food. However, questions still remain regarding the effects of low dose ionizing radiation exposure on the development and progression of cardiovascular diseases. We therefore investigated the effects of a chronic internal exposure to 137Cs on atherosclerosis in predisposed ApoE-/- mice. Mice were exposed daily to 0, 4, 20 or 100 kBq/l 137Cs in drinking water, corresponding to range of concentrations found in contaminated territories, for 6 or 9 months. We evaluated plaque size and phenotype, inflammatory profile, and oxidative stress status in different experimental groups. Results did not show any differences in atherosclerosis progression between mice exposed to 137Cs and unexposed controls. However, 137Cs exposed mice developed more stable plaques with decreased macrophage content, associated with reduced aortic expression of pro-inflammatory factors (CRP, TNFα, MCP-1, IFNγ) and adhesion molecules (ICAM-1, VCAM-1 and E-selectin). Lesions of mice exposed to 137Cs were also characterized by enhanced collagen and smooth muscle cell content, concurrent with reduced matrix metalloproteinase MMP8 and MMP13 expression. These results suggest that low dose chronic exposure of 137Cs in ApoE-/- mice enhances atherosclerotic lesion stability by inhibiting pro-inflammatory cytokine and MMP production, resulting in collagen-rich plaques with greater smooth muscle cell and less macrophage content.