Radiation-induced carotid artery lesions

Risk factors of post-irradiation carotid blowout syndrome in patients with nasopharyngeal carcinoma

PURPOSE

Carotid blowout syndrome (CBS) is a severe complication of radiotherapy in patients with nasopharyngeal carcinoma (NPC). This study is aimed at analyzing risk factors of post-irradiation CBS in patients with NPC.

METHODS

We retrospectively analyzed 660 patients with NPC between 2006 and 2019. The patients were divided into those with and without CBS, and their characteristics and outcomes were evaluated. Independent predictors of CBS were determined by multivariate logistic regression analysis.

RESULTS

We identified 17 NPC patients with CBS in our study. In multivariate logistic regression analysis, lower body mass index (BMI) (P = 0.018), tumor encasement (P = 0.039), local recurrence (P = 0.006), and skull base osteoradionecrosis (P < 0.001) were independent predictors of CBS, and a predictive equation model was established. Log-rank test revealed that patients with low BMI, tumor encasement of carotid vessels, local recurrence, and skull base osteoradionecrosis all exhibited shorter CBS-free time (all P < 0.001).

CONCLUSION

We demonstrated that low BMI, tumor encasement, local recurrence, and skull base osteoradionecrosis were independent predictors for CBS in NPC patients. Physicians can use these factors for the early detection and prevention of CBS.

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."

Impact of head and neck radiation on long-term outcomes after carotid revascularization

OBJECTIVE

Radiation-induced carotid artery stenosis (RICS) is a well-described phenomenon seen after head and neck cancer radiation. Previously published literature suggests that, compared with atherosclerotic disease, RICS may result in worse long-term outcomes and early restenosis. This study aims to evaluate the effect of radiation on long-term outcomes after various carotid revascularization techniques using a multi-center registry database.

METHODS

Patients in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) registry for carotid artery intervention (carotid endarterectomy [CEA]; transfemoral carotid artery stenting [CAS]; transcarotid artery revascularization [TCAR]), who are 65 years or older were included in the study. VQI Vascular Implant Surveillance and Interventional Outcomes Network (VISION) Medicare-linked database was used to obtain long-term procedure-specific outcomes. Primary endpoints were 3-year death, stroke, and reintervention. We performed propensity matching between patients with prior radiation and those without. Kaplan-Meier analysis and a multivariate logistic regression model were used to analyze the outcome variables.

RESULTS

A total of 56,472 patients had undergone carotid revascularization (CEA, n = 48,307; TCAR, n = 4593; CAS, n = 3572), 1244 patients with prior radiation and 54,925 patients without prior radiation. The prior radiation group was more likely to be male (71.9% vs 60.3%; P < .01), to receive a stent (47.5% vs 13.5%; P < .01), and to be on P2Y12 inhibitor (55.2% vs 38.3%; P < .01). Propensity matching was performed on 1223 patients (CEA, n = 655; TCAR, n = 292; CAS, n = 287). There were no significant differences in 30-day outcomes for death, stroke, or major adverse cardiovascular events for all three procedures. The prior radiation group had higher rates of cranial nerve injury (3.7% vs 1.8%; P = .04) and 90-day readmission (23.5% vs 18.3%; P = .01) after CEA. For long-term outcomes, prior radiation significantly increased mortality risk for CEA and CAS (hazard ratio [HR], 1.77; 95% confidence interval [CI], 1.38-2.27 and HR, 1.56; 95% CI, 1.02-2.36, respectively). The 3-year risk of stroke for CEA in radiated patients was also significantly higher (HR, 1.47; 95% CI, 1.03-2.09) compared with non-radiated patients. Prior radiation did not significantly affect death and stroke in patients undergoing TCAR. Prior radiation also did not impact the rates of short and long-term reintervention after CEA, CAS, or TCAR.

CONCLUSIONS

Prior head and neck radiation significantly increases the risk for mortality and stroke for CEA and the risk for mortality after CAS. Long-term outcomes for TCAR are not significantly affected by prior radiation. TCAR may be the preferred treatment modality for patients with radiation-induced carotid stenosis.

Carotid artery replacement with superficial femoral artery in a patient with recurrent radiation-induced carotid artery stenosis

A 58-year-old man presented with a right hemispheric transient ischemic attack from recurrent common carotid artery (CCA) in-stent restenosis. He had undergone prior neck radiation for carcinoma of the right tonsil and subsequent right carotid endarterectomy (10 years prior) and right CCA stenting (5 years prior), all for symptomatic radiation-induced stenosis. We performed CCA reconstruction using a transposed superficial femoral artery and pectoralis major myocutaneous flap coverage. Early stenosis of the proximal graft required angioplasty and stent grafting. However, at 1.5 years postoperatively, he has no further issues and a patent graft. This case highlights the options available for complex radiation-induced lesions of the carotid vessels.

Exploring the Link between Head and Neck Cancer and the Elevated Risk of Acute Myocardial Infarction: A National Population-Based Cohort Study

Enhanced screening protocols for cancer detection have increased survival in patients with head and neck cancer (HNC), which highlights the need to address the sequelae of therapy-induced cardiovascular complications. This study was conducted to assess the incidence and risk of acute myocardial infarction (AMI) in patients with HNC who have not undergone radiation or chemotherapy using a comprehensive, population-based cohort dataset. A total of 2976 individuals without cancer and 744 individuals with HNC were matched using the propensity score method. The findings indicated that the occurrence rates of AMI were comparable between the HNC (2.19) and non-cancer groups (2.39). Cox regression analysis did not demonstrate a significant increase in the risk of AMI in patients with HNC (hazard ratio: 0.93, 95% confidence interval: 0.50-1.73). No increased risk of AMI was observed in the HNC group compared to the non-cancer group, regardless of the time since the HNC diagnosis. Subgroup analyses showed no notable differences in the AMI risk between the groups when considering sex, age, comorbidities, and cancer type. This study showed that patients with HNC who have not been treated with radiation or chemotherapy did not exhibit an increased incidence or risk of AMI compared to individuals without cancer.

Neurological complications of modern radiotherapy for head and neck cancer

Radiotherapy is one of the mainstay treatment modalities for the management of non-metastatic head and neck cancer (HNC). Notable improvements in treatment outcomes have been observed in the recent decades. Modern radiotherapy techniques, such as intensity-modulated radiotherapy and charged particle therapy, have significantly improved tumor target conformity and enabled better preservation of normal structures. However, because of the intricate anatomy of the head and neck region, multiple critical neurological structures such as the brain, brainstem, spinal cord, cranial nerves, nerve plexuses, autonomic pathways, brain vasculature, and neurosensory organs, are variably irradiated during treatment, particularly when tumor targets are in close proximity. Consequently, a diverse spectrum of late neurological sequelae may manifest in HNC survivors. These neurological complications commonly result in irreversible symptoms, impair patients' quality of life, and contribute to a substantial proportion of non-cancer deaths. Although the relationship between radiation dose and toxicity has not been fully elucidated for all complications, appropriate application of dosimetric constraints during radiotherapy planning may reduce their incidence. Vigilant surveillance during the course of survivorship also enables early detection and intervention. This article endeavors to provide a comprehensive review of the various neurological complications of modern radiotherapy for HNC, summarize the current incidence data, discuss methods to minimize their risks during radiotherapy planning, and highlight potential strategies for managing these debilitating toxicities.

Progression rate of radiation-induced carotid stenosis in head and neck cancer survivors after statin treatment: a retrospective cohort study

BACKGROUND AND AIMS

Whether statin treatment is effective in retarding the progression of radiation-induced carotid stenosis (RICS) in head and neck cancer (HNC) survivors has not been well studied. The purpose of this study was to assess the association of statin treatment with RICS progression rate in HNC survivors after radiotherapy.

METHODS

We conducted a retrospective cohort study at Sun Yat-sen Memorial Hospital, Sun Yat-sen University in Guangzhou, China. Between January 2010 and December 2021, we screened HNC survivors whose carotid ultrasound scans had shown stenosis of the common and/or internal carotid arteries. The primary outcome was the RICS progression rate. We compared eligible patients treated with statins with those who did not in multivariable Cox regression models.

RESULTS

A total of 200 patients were included in this study, of whom 108 received statin treatment and 92 did not. Over a mean follow-up time of 1.5 years, 56 (28.0%) patients showed RICS progression, 24 (42.9%) and 32 (57.1%) in the statin and control groups, respectively. The statin group showed less RICS progression than the control group (adjusted-HR 0.49, 95% CI 0.30-0.80, P = 0.005). In the subgroup analysis, there was no significant interaction in the effect of statins on lowering RICS progression rate in the subgroups stratified by baseline low-density lipoprotein cholesterol (LDL-C) levels (P for interaction = 0.53) or baseline degrees of stenosis (P for interaction = 0.50).

CONCLUSIONS

Statin treatment was associated with a lower risk of RICS progression in patients with HNC after radiotherapy, regardless of baseline LDL-C level and baseline stenosis degrees.

Management of intervenable factors to reduce vascular complications in patients with internal carotid artery occlusion treated by non-emergency endovascular treatment

Objective

This study aims to identify risk factors for vascular complications during non-emergency endovascular treatment in patients with internal carotid artery occlusion (ICAO) and to propose potential interventions.

Method

A retrospective analysis of 92 patients with ICAO who received non-emergency endovascular treatment in our center from 1 January 2018 to 31 June 2023, was conducted. The correlation between intraoperative vascular complications and potential risk factors was studied, and interaction analysis was performed.

Results

Our findings revealed that the use of non-neurology guide wires to open vessels (adjusted OR: 4.1, 95%CI: 1.3-12.8; p = 0.014) and glycosylated hemoglobin (HbA1c) ≥ 6.5 mmol/L (adjusted OR: 3.2, 95%CI: 1.2-8.9; p = 0.023) was significantly associated with vascular complications in non-emergency endovascular treatment of ICAO patients. The restricted cubic spline (RCS) showed that the higher the HbA1c level, the higher the risk of vascular complications.

Conclusion

The use of non-neurology guide wires for vessel opening during non-emergency endovascular treatment in patients with ICAO increases the risk of vascular complications. Preoperative assessment and management of HbA1c levels can reduce the incidence of intraoperative vascular complications.

Neck radiation is not associated with increased risk of perioperative adverse events after transcarotid artery revascularization or transfemoral carotid artery stenting

OBJECTIVE

It is unclear whether patients with prior neck radiation therapy (RT) are at high risk for carotid artery stenting (CAS). We aimed to delineate 30-day perioperative and 3-year long-term outcomes in patients treated for radiation-induced stenotic lesions by the transfemoral carotid artery stenting (TFCAS) or transcarotid artery revascularization (TCAR) approach to determine comparative risk and to ascertain the optimal intervention in this cohort.

METHODS

Data were extracted from the Vascular Quality Initiative CAS registry for patients with prior neck radiation who had undergone either TCAR or TFCAS. The Student t-test and the χ2 test were used to compare baseline patient characteristics. Multivariable logistic regression and Cox Hazard Proportional analysis were used to compare perioperative and long-term differences between patients with and without prior neck radiation following TCAR and TFCAS. Kaplan-Meier estimator was used to determine the incidence of 3-year adverse events.

RESULTS

A total of 72,656 patients (TCAR, 40,879; TFCAS, 31,777) were included in the analysis. Of these, 4151 patients had a history of neck radiation. Patients with a history of neck radiation were more likely to be younger, white, and have fewer comorbidities than patients with no neck radiation history. After adjustment for confounding factors, there was no difference in relative risk of 30-day perioperative stroke (P = .11), death (P = .36), or myocardial infarction (MI) (P = .61) between TCAR patients with or without a history of neck radiation. The odds of stroke/death (P = .10) and stroke/death/MI (P = .07) were also not statistically significant. In patients with prior neck radiation, TCAR had lower odds for in-hospital stroke/death/MI (odds ratio, 0.59; 95% confidence interval [CI], 0.35-0.99; P = .05) and access site complications than TFCAS. At year 3, patients with prior neck radiation had an increased hazard for mortality after TCAR (hazard ratio [HR], 1.24; 95% CI, 1.02-1.51; P = .04) and TFCAS (HR, 1.33; 95% CI, 1.12-1.58; P = .001). Patients with prior neck radiation also experienced an increased hazard for reintervention after TCAR (HR, 2.16; 95% CI, 1.45-3.20; P < .001) and TFCAS (HR, 1.67; 95% CI, 1.02-2.73; P<.001).

CONCLUSIONS

Patients with prior neck radiation had a similar relative risk of 30-day perioperative adverse events as patients with no neck radiation after adjustment for baseline demographics and disease characteristics. In these patients, TCAR was associated with reduced odds of perioperative stroke/death/MI as compared with TFCAS. However, patients with prior neck radiation were at increased risk for 3-year mortality and reintervention.

Carotid endarterectomy for the management of carotid stenosis occurring concurrently with head and neck cancer

PURPOSE OF REVIEW

Currently, most patients with concurrent head and neck cancer (HNC) and carotid stenosis (CS) are treated disjointedly for their oncologic and vascular lesions. The purpose of this review is to evaluate literature exploring a novel approach to these cases that poses several advantages, in which carotid endarterectomy (CEA) is performed simultaneously with surgical resection of HNC.

RECENT FINDINGS

Carotid stenosis is a common comorbidity of patients presenting with head and neck cancer as these pathologies have overlapping risk factors. Adjuvant oncologic therapy such as radiation therapy to the site of the lesion is known to increase development or progression of carotid stenosis. Performing simultaneous surgical management of CS and HNC decreases total procedures for the patient, provides a less challenging surgical field, and eliminates prioritization of treatment initiation for one pathology over the other. There has been limited reporting of simultaneous CEA with oncologic resection of HNC in the literature. However, of the 21 cases reviewed here, no perioperative strokes were reported with only one perioperative death from myocardial infarction.

SUMMARY

Available literature supports that simultaneous CEA with oncologic resection of HNC is safe and may offer several advantages, although larger studies are required.

Ischemic stroke secondary to radiation-induced carotid artery stenosis

INTRODUCTION

Large vessel vasculopathy, such as carotid stenosis, has been shown to be a side effect of radiotherapy (RT) and has received increasing attention especially in recent decades with the improvement of RT technology. These injuries can lead to a higher risk of cerebrovascular events such as ischemic stroke. The management of these lesions may be performed with surgical repair but also with endovascular technique.

OBSERVATION

A 61-year-old man was admitted to the emergency department for an acute ischemic stroke. He was treated 16years prior for laryngeal tumor for which he had received 23 sessions of radiation therapy at the dose of 60Gy per session. The CT scan showed a radiation-induced stenosis of the right internal carotid artery with thrombosis of the right anterior cerebral artery and the right middle cerebral artery. The patient was treated with angioplasty of the right internal carotid artery with good outcome.

CONCLUSION

Radiation-induced vasculopathy of the carotid artery has gained relevance in patients with head and neck neoplasms. These vascular lesions are associated with the risk of late cerebrovascular events.

Comparison of Arterial Stiffness and Strain Measured with Speckle Tracking Carotid Strain Ultrasonography after Radiation and Surgical Treatment for Head and Neck Cancer-A Clinical Trial

This study assessed arterial stiffness in head and neck cancer patients using speckle tracking carotid strain ultrasonography (STCS-US). It investigated the impacts of neck irradiation and neck dissection on the arterial stiffness of these patients by comparing their stiffness parameters with those of healthy controls. A total of 101 participants (67 patients and 34 healthy controls) were enrolled in this study. Fifty-two patients received definitive radiation therapy (TD: 60-72 Gy in 30 days) at least two years ago. Participants were grouped into four according to their states of neck irradiation (IR) and neck dissection (ND): Group (IR+/ND-) had 28 patients, Group (IR+/ND+) had 24 patients, Group (IR-/ND+) had 15 patients, and Group (IR-/ND-) had 34 healthy controls. All the participants underwent STCS-US. Arterial stiffness parameters relating to arterial compliance (AC) and elastic modulus (EM) were significantly changed in Group (IR+/ND-) and Group (IR+/ND+) in the transverse plane (p < 0.001, p < 0.001) and in the longitudinal plane (p < 0.001, p < 0.001); the change in β-stiffness index (β-SI) was more significant in the transverse plane (p = 0.002). Group (IR+/ND+) had significant transverse circumferential (p = 0.001) and radial strain parameters (p = 0.001). The carotid intimal medial thickness (CIMT) significantly changed in Group (IR+/ND+) compared to controls (p = 0.001). Our findings indicate that neck irradiation and neck dissection increase arterial stiffness as single treatments; however, double treatment is associated with a higher increase. Neck irradiation affects strain parameters more than neck dissection alone. The study demonstrated the feasibility and clinical value of the STCS method in assessing arterial stiffness and its potential use in cardiovascular risk assessment for patients with head and neck cancer.

Identifying the Cause of Acute Left-Sided Visual Loss: A Clinical Dilemma

Given the global increase in the incidence of head and neck cancers over the last decade, the use of chemoradiation has also increased. It is well known that chemotherapy/radiation are established standard therapies in head and neck cancers, especially in patients who are not candidates for surgery. Despite this increase in chemoradiation therapies in head and neck cancers, there is a lack of established guidelines on the surveillance and screening of these patients for long-term complications. We present an interesting case of acute left eye blindness in a veteran patient with a history of laryngeal cancer status post chemoradiation and in the setting of a left ventricular (LV) thrombus on anticoagulation resulting in a diagnostic challenge determining the etiology. This case emphasizes the need for thorough patient-centered annual evaluation, thus providing an opportunity for early noninvasive or minimally invasive intervention.

Case report of intracranial large vessel occlusion in glioblastoma multiforme patient after radiation therapy

INTRODUCTION

Vasculopathy of the large arteries is a prominent complication of radiotherapy. Radiation-induced cerebral vasculopathy can cause arterial stenosis/occlusion, cerebral hemorrhage, and aneurysm formation. We report a cases of glioblastoma multiforme (GBM) with occlusive radiation vasculopathy (ORV).

CASE PRESENTATION

This 28-year-old patient who suffered from GBM had surgery for cytoreduction and received postoperative CCRT. We adopted the radiotherapy and oncology group radiation guideline. This patient had cerebrovascular accident episodes without any known risk. Therefore, ORV was highly suspected and vascular stenosis was confirmed using magnetic resonance angiography (MRA) or digital subtraction angiography. Extracranial-intracranial bypass was performed and patency was confirmed. The patient had not suffered from recurrent symptoms of transient ischemic attack or ischemic stroke for 1.5 years.

DISCUSSION

This is the first article to report bypass surgery for GBM patients. Although the median survival rate of GBM is approximately 15 months, the short survival time may be sufficient for occlusive vasculopathy to occur. Regular follow-up magnetic resonance imaging assessments are recommended, as is MRA as a screening tool for the early diagnosis of ORV.The Stenting versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial focused on atherosclerotic intracranial arterial stenosis, revealing that aggressive medical management was superior to stenting for secondary stroke prevention; however, it did not mention radiation-induced vasculopathy. Bypass surgery has yielded some positive outcomes. In the absence of contraindications, antiplatelet or anticoagulation agents could be added, and bypass surgery could be performed because there was no stent in the distal intracranial arteries.

CONCLUSION

MRA is a potential screening tool for ORV in GBM patients and bypass surgery could be performed to improve brain perfusion. Bypass surgery could help patient with occlusive radiation vasculopathy.

Late Radiation-Induced Carotid Artery Stenosis and Stroke in Pediatric Patient Treated With Proton Radiation Therapy for Skull-Base Chordoma

Radiation vasculopathy is a well-recognized late complication of radiation therapy. We present a case of a stroke 29 years after high-dose proton radiation therapy for skull-base chordoma due to occlusion of bilateral internal carotid arteries.

The Lymphatic Endothelium in the Context of Radioimmuno-Oncology

The study of lymphatic tumor vasculature has been gaining interest in the context of cancer immunotherapy. These vessels constitute conduits for immune cells' transit toward the lymph nodes, and they endow tumors with routes to metastasize to the lymph nodes and, from them, toward distant sites. In addition, this vasculature participates in the modulation of the immune response directly through the interaction with tumor-infiltrating leukocytes and indirectly through the secretion of cytokines and chemokines that attract leukocytes and tumor cells. Radiotherapy constitutes the therapeutic option for more than 50% of solid tumors. Besides impacting transformed cells, RT affects stromal cells such as endothelial and immune cells. Mature lymphatic endothelial cells are resistant to RT, but we do not know to what extent RT may affect tumor-aberrant lymphatics. RT compromises lymphatic integrity and functionality, and it is a risk factor to the onset of lymphedema, a condition characterized by deficient lymphatic drainage and compromised tissue homeostasis. This review aims to provide evidence of RT's effects on tumor vessels, particularly on lymphatic endothelial cell physiology and immune properties. We will also explore the therapeutic options available so far to modulate signaling through lymphatic endothelial cell receptors and their repercussions on tumor immune cells in the context of cancer. There is a need for careful consideration of the RT dosage to come to terms with the participation of the lymphatic vasculature in anti-tumor response. Here, we provide new approaches to enhance the contribution of the lymphatic endothelium to radioimmuno-oncology.

Tissue Reactions and Mechanism in Cardiovascular Diseases Induced by Radiation

The long-term survival rate of cancer patients has been increasing as a result of advances in treatments and precise medical management. The evidence has accumulated that the incidence and mortality of non-cancer diseases have increased along with the increase in survival time and long-term survival rate of cancer patients after radiotherapy. The risk of cardiovascular disease as a radiation late effect of tissue damage reactions is becoming a critical challenge and attracts great concern. Epidemiological research and clinical trials have clearly shown the close association between the development of cardiovascular disease in long-term cancer survivors and radiation exposure. Experimental biological data also strongly supports the above statement. Cardiovascular diseases can occur decades post-irradiation, and from initiation and development to illness, there is a complicated process, including direct and indirect damage of endothelial cells by radiation, acute vasculitis with neutrophil invasion, endothelial dysfunction, altered permeability, tissue reactions, capillary-like network loss, and activation of coagulator mechanisms, fibrosis, and atherosclerosis. We summarize the most recent literature on the tissue reactions and mechanisms that contribute to the development of radiation-induced cardiovascular diseases (RICVD) and provide biological knowledge for building preventative strategies.

Cancer and stroke: commonly encountered by clinicians, but little evidence to guide clinical approach

The association between stroke and cancer is well-established. Because of an aging population and longer survival rates, the frequency of synchronous stroke and cancer will become even more common. Different pathophysiologic mechanisms have been proposed how cancer or cancer treatment directly or via coagulation disturbances can mediate stroke. Increased serum levels of D-dimer, fibrin degradation products, and CRP are more often seen in stroke with concomitant cancer, and the clot retrieved during thrombectomy has a more fibrin- and platelet-rich constitution compared with that of atherosclerotic etiology. Multiple infarctions are more common in patients with active cancer compared with those without a cancer diagnosis. New MRI techniques may help in detecting typical patterns seen in the presence of a concomitant cancer. In ischemic stroke patients, a newly published cancer probability score can help clinicians in their decision-making when to suspect an underlying malignancy in a stroke patient and to start cancer-screening studies. Treating stroke patients with synchronous cancer can be a delicate matter. Limited evidence suggests that administration of intravenous thrombolysis appears safe in non-axial intracranial and non-metastatic cancer patients. Endovascular thrombectomy is probably rather safe in these patients, but probably futile in most patients placed on palliative care due to their advanced disease. In this topical review, we discuss the epidemiology, pathophysiology, and prognosis of ischemic and hemorrhagic strokes as well as cerebral venous thrombosis and concomitant cancer. We further summarize the current evidence on acute management and secondary preventive therapy.

Plaque Protrusion in a Patient with Left Common Carotid Artery Stenting after Radiation Therapy: A Case Report

Objective

We report a case of additional carotid artery stenting (CAS) for plaque protrusion occurring after initial CAS for radiation-induced common carotid artery (CCA) stenosis.

Case Presentation

A 69-year-old man with a history of radiotherapy for laryngeal cancer presented to our hospital with sudden-onset right hemiparesis. Since vulnerable plaque of the left CCA was considered the embolic source for ischemic stroke, CAS was performed for left CCA stenosis. No perioperative complications were observed and the patient was discharged with a modified Rankin Scale score of 0. However, 1 month after CAS, cerebral embolism recurred. As protruding plaque was found on CTA, additional endovascular treatment was performed with intravascular ultrasonography. He was discharged without complications and showed a good outcome at 3 months.

Conclusion

In CCA stenosis after radiotherapy, accelerated arteriosclerosis may cause drug-resistant cerebral embolism and plaque protrusion after CAS, making determination of the treatment strategy difficult. Appropriate treatment options need to be based on individual underlying diseases and plaque instability.

Adverse Radiation Therapy Effects in the Treatment of Head and Neck Tumors

Whether used as a single modality or as part of a combined approach, radiation therapy (RT) plays an essential role in the treatment of several head and neck malignancies. Despite the improvement in radiation delivery techniques, normal structures in the vicinity of the target area remain susceptible to a wide range of adverse effects. Given their high incidence, some of these effects are referred to as expected postradiation changes (eg, mucositis, sialadenitis, and edema), while others are considered true complications, meaning they should not be expected and can even represent life-threatening conditions (eg, radionecrosis, fistulas, and radiation-induced neoplasms). Also, according to their timing of onset, these deleterious effects can be divided into four groups: acute (during RT), subacute (within weeks to months), delayed onset (within months to years), and very delayed onset (after several years).The authors provide a comprehensive review of the most important radiation-induced changes related to distinct head and neck sites, focusing on their typical cross-sectional imaging features and correlating them with the time elapsed after treatment. Radiologists should not only be familiar with these imaging findings but also actively seek essential clinical data at the time of interpretation (including knowledge of the RT dose and time, target site, and manifesting symptoms) to better recognize imaging findings, avoid pitfalls and help guide appropriate management. ^© RSNA, 2022.

Evaluation of Intima-Media Thickness and Arterial Stiffness as Early Ultrasound Biomarkers of Carotid Artery Atherosclerosis

Carotid atherosclerosis is a major and potentially preventable cause of ischemic stroke. It begins early in life and progresses silently over the years. Identification of individuals with subclinical atherosclerosis is needed to initiate early aggressive vascular prevention. Although carotid plaque appears to be a powerful predictor of cardiovascular risk, carotid intima-media thickness (CIMT) and arterial stiffness can be detected at the initial phases and, therefore, they are considered important new biomarkers of carotid atherosclerosis. There is a well-documented association between CIMT and cerebrovascular events. CIMT provides a reliable marker in young people, in whom plaque formation or calcification is not established. However, the usefulness of CIMT measurement in the improvement of risk cardiovascular models is still controversial. Carotid stiffness is also significantly associated with ischemic stroke. Carotid stiffness adds value to the existing risk prediction based on Framingham risk factors, particularly individuals at intermediate cardiovascular risk. Carotid ultrasound is used to assess carotid atherosclerosis. During the last decade, automated techniques for sophisticated analysis of vascular mechanics have evolved, such as speckle tracking, and new methods based on deep learning have been proposed with promising outcomes. Additional research is needed to investigate the imaging-based cardiovascular risk prediction of CIMT and stiffness.

Correction of carotid artery stenosis by stent placement ameliorated paroxysmal hypertension after radiation treatment of hypopharyngeal carcinoma: a case report

Background

Paroxysmal hypertension can be associated with failure of the carotid artery baroreceptors due to past exposure to radiation treatment. This report describes a patient whose repeated paroxysmal hypertensive episodes were ameliorated following placement of a carotid artery stent for the treatment of carotid artery stenosis.

Case report

A 79-year-old caucasian male was diagnosed with hypopharyngeal squamous cell carcinoma (T1, L0, M0) in 2006, and received 70 Gy intensity-modulated radiotherapy in 2006 and underwent a total laryngectomy in 2008. He experienced paroxysmal hypertensive episodes since 2010 that exacerbated in frequency in 2019. Eighty percent left internal carotid artery stenosis was demonstrated by ultrasound and arteriography. Angioplasty and stenting of the left carotid artery was performed. A Doppler ultrasound study performed 5 months after the stent placement did not reveal any hemodynamic stenosis in the left carotid artery. The patient experienced postprandial hypotension and had experienced only three episodes of paroxysmal hypertension in the following 24 months. He was able to abort paroxysmal hypertensive episodes by eating warm food.

Discussion

This is the first report of a patient whose paroxysmal hypertensive episodes that occurred following radiation of the neck subsided after placement of a stent in a stenotic carotid artery. The exact mechanism leading to this phenomena is unknown but may be due to several factors. The reversal of the carotid artery stent and improvement in blood flow to the carotid artery baroceptors may play a role in this phenomenon.

Conclusion

The ability to ameliorate paroxysmal hypertensive episodes in a patient with carotid artery stenosis by stent placement may be a promising therapeutic intervention for paroxysmal hypertension.

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.

Early-Stage Glottic Squamous Cell Carcinoma in the Era of Image-Guided Radiotherapy

Early-stage squamous cell cancer (SCC) of the glottis has a good prognosis. Therefore, patients have long survival outcomes and may potentially suffer from late toxicities of radiotherapy. Radiotherapy with a conventional parallel-opposed-pair or anterior-oblique beam arrangements for stage 1 and 2 glottic SCC have field borders that traditionally cover the entire larynx, exposing organs-at-risk (e.g. carotid arteries, contralateral vocal cord, contralateral arytenoid and inferior pharyngeal constrictor muscles) to high radiation doses. The potential long-term risk of cerebrovascular events has attracted much attention to the dose that carotid arteries receive. Swallow and respiratory motion of laryngeal structures has been an important factor that previously limited reduction of the radiation treatment volume. Motion has been evaluated using multiple imaging modalities and this information has been used to calculate PTV margins for generation of more limited target volumes. This review discusses the current literature surrounding dose-effect relationships for various organs-at-risk and the late toxicities that are associated with them. This article also reviews the currently available data and effects of laryngeal motions on dosimetry to the primary target. We also review the current limitations and benefits of a more targeted approach of radiotherapy for early-stage glottic SCCs and the evolution of CT-based IGRT and MR-guided radiotherapy techniques that may facilitate a shift away from a conventional 3D-conformal radiotherapy approach.

Perioperative outcomes of carotid endarterectomy and transfemoral and transcervical carotid artery stenting in radiation-induced carotid lesions

OBJECTIVE

Limited data are available to guide the choice of intervention for patients with radiation-induced carotid stenosis (RICS), either transcarotid artery revascularization (TCAR), transfemoral carotid artery stenting (TFCAS), or carotid endarterectomy (CEA). The purpose of the present study was to evaluate patients who had undergone these carotid artery interventions for RICS and the associated outcomes.

METHODS

Patients in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) carotid artery stenting surveillance project registry and the SVS VQI CEA modules who had undergone carotid artery intervention (TCAR, TFCAS, or CEA) for RICS were included. Those aged >90 years and those with concomitant interventions (eg, coronary bypass) were excluded. A composite of death, myocardial infarction (MI), and stroke was the primary outcome. The secondary outcomes included death, MI, stroke, cranial nerve injury (CNI), and other local and systemic complications. Multivariable logistic regression controlling for presenting symptomatic status and comorbid medical conditions was conducted for the outcome variables, except for death, which was analyzed using Cox regression modeling.

RESULTS

A total of 1927 patients with RICS had undergone CEA (n = 1172), TCAR (n = 253), or TFCAS (n = 502). The CEA group had a higher rate of diabetes (31% vs 25% for TCAR and 25% for TFCAS; P = .01), hypertension (85% vs 82% for TCAR and 79% for TFCAS; P < .01), and peripheral vascular disease (8% vs 4% for TCAR and 4% for TFCAS; P < .01). The TCAR and TFCAS groups had higher rates of coronary artery disease (21% for CEA vs 30% for TCAR and 29% for TFCAS; P < .01). The patients who had undergone TFCAS were more likely to have had symptomatic lesions (57% for TFCAS vs 47% for CEA and 41% for TCAR; P < .01) and prior stroke (55% for TFCAS vs 47% for CEA and 40% for TCAR; P < .001). The composite outcome occurred in 3.2% of TCAR patients, 11.2% of TFCAS patients, and 11.1% of CEA patients (P < .01) with an odds ratio of 0.27 for TCAR, 0.91 for TFCAS, and 1.00 for CEA. However, no differences in the individual outcomes were noted for any procedure. TCAR exhibited the lowest odds ratio for CNI (0.15) compared with TFCAS at 0.9, both relative to CEA (P = .03).

CONCLUSIONS

RICS patients treated by TCAR in the SVS VQI had the lowest risk of the composite of stroke, death, and MI and CNI. Therefore, TCAR might be the preferred treatment modality. Further comparative studies are needed to evaluate the long-term outcomes in this population and to elucidate the relationship of these procedures to the individual outcomes of stroke, MI, and death.

Increased risk of cerebrovascular mortality in head and neck cancer survivors aged ≥ 65 years treated with definitive radiotherapy: a population-based cohort study

Background

To investigate the relationship between radiotherapy (RT) and the risk of cerebrovascular mortality (CVM) in head and neck cancer (HNC) survivors aged ≥ 65 years.

Methods

Patients with HNC survivors aged ≥ 65 years diagnosed between 2000 and 2012 were included from the Surveillance, Epidemiology, and End Results database. Kaplan–Meier analysis, Log-rank tests, and Cox proportional-hazards regression models were performed for statistical analyses.

Results

We included 16,923 patients in this study. Of these patients, 7110 (42.0%) patients received surgery alone, 5041 (29.8%) patients underwent RT alone, and 4772 (28.2%) patients were treated with surgery and RT. With a median follow-up time of 87 months, 1005 patients died with cerebrovascular disease. The 10-years CVM were 13.3%, 10.8%, and 11.2% in those treated with RT alone, surgery alone, and surgery plus RT, respectively (P < 0.001). The mean time for CVM was shorter in RT alone compared to surgery alone and surgery plus RT (52 months vs. 56–60 months). After adjusting for covariates, patients receiving RT alone had a significantly higher risk of developing CVM compared to those receiving surgery alone (hazard ratio [HR] 1.703, 95% confidence interval [CI] 1.398–2.075, P < 0.001), while a comparable risk of CVM was found between those treated with surgery alone and surgery plus RT (HR 1.106, 95% CI 0.923–1.325, P = 0.274). Similar trends were found after stratification age at diagnosis, gender, tumor location, and marital status.

Conclusions

Definitive RT but not postoperative RT can increase the risk of CVM among older HNC survivors. Long-term follow-up and regular screening for CVD are required for HNC patients who received definitive RT to decrease the risk of CVM.

Significant Reduction in Vertebral Artery Dose by Intensity Modulated Proton Therapy: A Pilot Study for Nasopharyngeal Carcinoma

Intensity modulated proton therapy (IMPT) with the vertebral artery (VA)-sparing technique has been initially proposed in our institution. This pilot study was conducted to compare the dose to VAs between IMPT and volumetric-modulated arc therapy (VMAT) for patients with nasopharyngeal carcinoma (NPC). A total of six patients with NPC treated by IMPT were enrolled in the study. Target volumes and organs at risk (OARs) were delineated, including 12 samples of right and left VAs, respectively, for each patient. Treatment planning by IMPT and dual-arc VMAT was carried out for comparison. The IMPT plan significantly reduced VA mean dose, V10, V20, V30, V40, and V50, compared to the VMAT plan in all 12 samples (p < 0.001). The average mean dose to VAs for IMPT was 35.2% (23.4–46.9%), which was less compared to VMAT (p < 0.001). Adequate dose coverage was achieved with both IMPT and VMAT plans for three different dose levels of target volumes for all patients. IMPT significantly reduces VA dose while maintaining adequate dose coverage of all target volumes. For patients with head and neck cancer who seek to preserve their blood flow to the brain in order to decrease late vascular and neurologic sequelae, IMPT should be considered. A prospective study with longer follow-up is ongoing to confirm our preliminary results.

Embolization for Carotid Blowout in Head and Neck Cancer: Case Report of Five Patients

Carotid blowout syndrome (CBS) is defined as a rupture of common carotid artery or its branches. Endovascular intervention has been advocated as first line of treatment for CBS. This Case Report describes 5 patients with prior history of head and neck cancer who presented with CBS. Two patients presented as acute, 2 as impending, and one as threatened CBS. The lesions found were pseudoaneurysm and focal vascular irregularities involving the common carotid artery, cervical internal carotid artery and lingual artery. Embolization and occlusion with detachable coils of the artery was used in all patients. Technical success and immediate hemostasis were achieved in all patients. One patient presented transient cranial nerve palsy. No recurrent CBS was reported during the follow-up. In our experience, coil embolization, if possible, is a safe and efficient technique in treatment of CBS secondary to head and neck cancers.

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

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

Computer-assisted ultrasound assessment of plaque characteristics in radiation-induced and non-radiation-induced carotid atherosclerosis

Background

This study investigated the feasibility of using a computer-assisted method to evaluate and differentiate the carotid plaque characteristics in radiation-induced and non-radiation-induced carotid atherosclerosis.

Methods

This study included 107 post-radiotherapy (post-RT) nasopharyngeal carcinoma (NPC) patients and 110 subjects with cardiovascular risk factors (CVRFs). Each participant had a carotid ultrasound examination, and carotid plaques and carotid intima-media thickness (CIMT) were evaluated with grey scale ultrasound. The carotid plaque characteristics were evaluated for grey-scale median (GSM) and detailed plaque texture analysis (DPTA) using specific computer software. In DPTA, five different intra-plaque components were colour-coded according to different grey scale ranges. A multivariate linear regression model was used to evaluate the correlation of risk factors and carotid plaque characteristics.

Results

Post-RT NPC patients have significantly higher CIMT (748±15.1 µm, P=0.001), more patients had a plaque formation (80.4%, P<0.001) and more plaque locations (2.3±0.2, P<0.001) than CVRF subjects (680.4±10.0 µm, 38.2% and 0.5±0.1 respectively). Among the five intra-plaque components, radiation-induced carotid plaques had significantly larger area of calcification (4.8%±7.7%, P=0.012), but lesser area of lipid (42.1%±16.9%, P=0.034) when compared to non-radiation-induced carotid plaques (3.0%±5.7% and 46.3%±17.9% respectively). Age, radiation and number of CVRF were significantly associated with the carotid atherosclerosis burden (P<0.001). Besides, age was significantly associated with the amount of lipid and calcification within carotid plaques (P<0.001).

Conclusions

Radiation caused more severe carotid artery disease than CVRF with larger CIMT and more prevalent of carotid plaque. Radiation-induced carotid plaques tended to have more intra-plaque calcifications, whereas non-radiation-induced carotid plaques had more lipids. Ultrasound aided by computer-assisted image analysis has potential for more accurate assessment of carotid atherosclerosis.

Assessing the short-term effects of radiotherapy on the shear modulus of the common carotid artery as a new biomarker of radiation-induced atherosclerosis

Purpose

The purpose of this study was to investigate the incidence of short-term atherosclerosis in the common carotid arteries following radiotherapy.

Methods

The mean radiation dose to the arteries was 49.30±15.83 Gy. A computational ultrasound method was introduced to investigate the elastic modulus. Ultrasonography was performed 2-3 cm inferior to the bifurcation region before and after radiotherapy, and sequential images were extracted from a video of each artery. Instantaneous movement of the arterial wall in the radial and longitudinal directions was extracted by implementing the maximum gradient and block matching algorithms, respectively.

Results

There was a significant change in systolic blood pressure after radiotherapy (P=0.008). Irradiated arteries had significantly smaller systolic and end-diastolic diameters than non-irradiated arteries (P<0.001). The shear modulus was significantly different between irradiated and non-irradiated arteries (3.10±2.03 kPa vs. 1.38±0.98 kPa, P<0.001). The shear and Young moduli of radiation-induced arteries were 2.25±1.50 and 1.57±0.59 times higher than those of the pre-irradiation arteries.

Conclusion

The arterial shear modulus can be considered as a new biomarker of radiation-induced atherosclerosis in the common carotid artery.

Radiation-induced lower-limb arteriopathy: report of 4 cases and systematic literature review

INTRODUCTION

Radiation-induced arteriopathy (RIA) is a rare complication but may become more common due to the increased use of radiotherapy and the prolonged survival of patients. There is still a lack of evidence concerning treatment options. The aim of this study is to review reported cases of lower-limb RIA in order to provide guidelines for management.

EVIDENCE ACQUISITION

We reported 4 cases treated for lower limb RIA and performed a systematic literature review without time limitation in the Medline database using the MeSh tems "iliac artery/radiation effects" OR "femoral artery/radiation effects." Main outcomes of interest were radiation dose, time before symptoms, symptoms, involved vessels, treatment and outcome.

EVIDENCE SYNTHESIS

Twenty-five studies were included, reporting a total of 43 patients. Median time between irradiation and symptoms was 12 years (range: 9 days-49 years), with a median irradiation dose of 40Gy. Clinical presentation was claudication in 18 patients (52%), critical limb threatening ischemia (CLTI) in 4 patients (11%), acute limb ischemia (ALI) in 3 patients (9%) and hemorrhage in 6 patients (17%), the remaining 4 patients were asymptomatic (11%). Vessels involved were iliac arteries in 65% of the cases, femoropopliteal arteries in 28% of cases and concomitant supra and infrainguinal vessels in 7% of the cases. Claudication was mostly treated by open surgery (62%). Treatment of CLTI included primary amputation (50%), open surgery (25%) or endovascular surgery (25%). ALI was treated medically (33%), by open surgery (33%) or in situ thrombolysis (33%). Hemorrhagic cases or pulsatile masses were mostly treated by open surgery (66%). Follow-up was reported in 26 patients (67%), with mean follow-up of 12 months (range: 2 weeks - 5 years). During follow-up, 16% of these patients presented a recurrence of symptoms, and 8% required a reintervention.

CONCLUSIONS

There seems to be no evidence for open versus endovascular treatment, but close and long-term follow-up is needed in these patients due to the possible late presentation and recurrence of symptoms after treatment.

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.

Medical prevention and treatment of radiation-induced carotid injury

Radiotherapy has significantly improved the survival of cancer patients but is also associated with several adversities, including radiation-induced carotid injury (RICI). The RICI mechanisms are complex, including vessel inflammatory injury, carotid atherosclerosis, intimal proliferation, media necrosis, and peri-adventitial fibrosis. The main manifestation and adverse consequence of RICI is carotid artery stenosis (CAS), which can lead to stroke and transient ischemic attack. Currently, carotid artery injury is primarily diagnosed via color-coded duplex sonography. Early detection of traumatic changes in the carotid artery depends on measurements of carotid intima-media thickness; serum biomarker testing also shows great potential. CAS is mainly treated with carotid endarterectomy or carotid angioplasty and stent implantation. Notably, bone marrow mesenchymal stem cells are advantageous in RICI treatment and reduce carotid inflammation, oxidative stress, and delaying atherosclerosis. This review summarizes the mechanisms, examination methods, and latest treatments for RICI to provide data for its clinical prevention and treatment.

Late side effects of radiation treatment for head and neck cancer

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

Clinical outcomes of radiation-induced carotid stenosis: A systematic review and meta-analysis

OBJECTIVES

Clinical outcomes of radiation-induced carotid stenosis are still unclear. Therefore, a systematic review and meta-analysis is needed to evaluate the short- and long-term outcomes after interventions to treat radiation-induced carotid stenosis.

METHODS

PubMed, EMBASE, the Cochrane Library and Web of Science were searched from 1 January 2000 for relevant RCTs and observational studies which reported outcomes after carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS) for carotid stenosis induced by radiation. Risk of bias were assessed through different scales according to study design. I² statistic were used to evaluate the heterogeneity, and meta-regression were performed to investigate the source of heterogeneity. Visual inspection of funnel plots was used to judge publication bias.

RESULTS

A total of 26 studies with 1002 patients were included. CEA was performed in 364 patients and CAS in 638 patients. The overall estimated rate of short-term stroke was 0.19% (95% CI: 0-0.90%), and the rate of long-term stroke was 2.68 % (95% CI: 1.19-4.57%). The rate of cranial nerve injury in CEA group was significantly higher than that in CAS group [risk ratio (RR): 6.03, 95% CI: 1.63-22.22, P = .007]. The univariate regression analysis showed that the risk of stroke in CAS group were significantly higher than CEA group in both short- and long-term [incidence rate ratio (IRR): 3.62, 95% CI: 1.21-10.85, P = 0.22; IRR: 2.95, 95% CI: 1.02-8.59, P = .046, respectively].

CONCLUSIONS

This systematic review provided the worldwide profile of outcome of treatment for radiation-induced carotid stenosis, and also found that CEA can yield better results for these patients than CAS. Nonetheless, as large-scale studies have not yet been conducted, and there is a definite need for further studies in the future.

Preliminary Simulation Study of Carotid Artery and Pharyngeal Constrictor Muscle Sparing-Radiotherapy in Glottic Carcinoma

Background:

This preliminary simulation study aimed to compare the dosimetric outcomes of carotid arteries (CAs) and pharyngeal constrictor muscle (PCM) in patients with T1N0M0 glottic carcinoma undergoing helical tomotherapy-intensity modulated radiotherapy (HT-IMRT) and 3-dimensional conformal radiotherapy (3D-CRT) plans.

Methods:

In addition to the clinical target volume (CTV) which was defined as the entire larynx, the CAs and PCM of 11 glottic carcinoma patients were delineated. The CTV was uniformly expanded 5 mm to create a planning target volume (PTV) relative to the PCM and at a distance of 2 mm from the CA. The dosimetric characteristics in HT-IMRT and lateral opposed fields-based 3D-CRT plans were analyzed.

Results:

Median D_95%and V_100% of PTV were significantly higher in HT-IMRT (p < 0.001) compared to 3D-CRT. The right/left CA dosimetric outcomes, including the mean doses (20.7/21.5 Gy versus 48.7/50.5 Gy), D_max (53.6/52.0 Gy versus 67.4/67.7 Gy), V₃₀ (25.0/27.1% versus 77.6/80.3%), V₄₀ (8.0/7.9% versus 74.6/71.9%), and V₅₀ (2.0/1.2% versus 70.0/71.6%) were also significantly lower in HT-IMRT (p < 0.05), similar to the mean PCM doses (49.6 Gy versus 62.6 Gy for 3D-CRT;p < 0.001), respectively.

Conclusions:

Our present results demonstrated the feasibility of simultaneous sparing of the CAs and PCM in HT-IMRT- compared to 3D-CRT plans in glottic carcinoma patients undergoing definitive radiotherapy.

Management of Radiation Induced Carotid Stenosis in Head and Neck Cancer

OBJECTIVES: Presentation of radiation-induced lesions in carotid arteries of patients with head and neck squamous cell carcinoma (HNSCC) and the evaluation of the effectiveness of endovascular treatment of symptomatic stenoses. MATERIALS AND METHODS: We retrospectively analyzed 26 patients who underwent surgery and subsequently cervical radiotherapy (RT) for HNSCC, focusing on radiation-induced vascular disease in neck arteries—from the latency period to the occurrence of neurological events—and the endovascular treatment of the internal carotid artery (ICA) and/or of common carotid artery (CCA) stenoses. The vascular lesions were diagnosed with Doppler ultrasonography and selective digital angiography. Patients with >70% stenoses of ICA and/or CCA were scheduled for carotid artery stenting (CAS). They were followed-up with neurological examinations and Doppler ultrasonography at 6, 12, and 24 months after stenting. RESULTS: Radiation-induced vascular diseases occurred in the ICA in 22 patients (85%), CCA in 15 (58%), and in ECA in 15 (58%). The stents were implanted in 25 ICA and 17 CCA. Thirteen patients (50%) had one stent, eight (30%) had two stents, four (15%) had three stents, and one patient had five stents. Overall, 46 stents were implanted. Technical success was achieved in all patients. No cerebrovascular events occurred in the 24-months follow-up. CONCLUSION: RT in patients with HNSCC holds a significant risk factor of developing carotid artery stenosis and cerebrovascular events. Carotid stenting is preferable mode of treatment for radiation-induced stenosis. A screening program with doppler ultrasonography enables pre-stroke detection of carotid stenosis.

Nontraumatic Vascular Emergencies of the Neck

Nontraumatic vascular emergencies of the head and neck are uncommon, but can occur in patients with central venous catheters, head and neck infections, and in patients with head and neck cancer. Recognizing the imaging findings of vascular complications in these patient populations is critically important to ensure expeditious treatment to avoid significant morbidity and mortality.

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.