Changes in the Common Carotid Artery after Radiotherapy: Wall Thickness, Calcification, and Atherosclerosis

Carotid Artery Stenosis and Ischemic Stroke in Patients With Head and Neck Cancer Treated With Radiation Therapy: A Critical Review

The purpose of this review is to summarize the literature on carotid artery stenosis (CAS) and ischemic stroke (IS) in patients with head and neck cancer (HNC) treated with radiation therapy (RT) to guide assessment, screening, and management strategies. Patients treated with RT for HNC are at an elevated risk of developing CAS, with published meta-analyses demonstrating that CAS >50% occurs in approximately 25% of patients. Previous research suggests a 10-year cumulative incidence of stroke between 5.7% and 12.5%. Cardiovascular disease (CVD) risk prediction tools such as Qstroke, QRISK-2, and Framingham risk score perform poorly for predicting IS for patients with HNC who received RT. Duplex ultrasound is the most common imaging modality to assess CAS, but controversy remains as to the utility of screening asymptomatic individuals. Only 3 of the 5 major HNC survivorship guidelines acknowledge RT as a risk factor for CAS or IS, while only 1 makes a specific recommendation on screening for CAS (American Head and Neck Society). Within the general population, only 1 CVD guideline discusses RT as a risk factor for CAS (Society for Vascular Surgery). Clinicians involved in the care of patients with HNC treated with RT should be aware of the increased risk of CAS and IS and the challenges in risk prediction. Although there is a lack of evidence to make firm recommendations, HNC survivorship recommendations should ensure HNC survivors and primary care providers are informed of these risks and the importance of assessment and management of CVD risk factors. Future studies are required to refine risk prediction models in patients with HNC and to determine those most likely to benefit from targeted screening and initiation of early preventative strategies.

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.

Association between modifiable vascular risk factors and rapid progression of postradiation carotid artery stenosis

BACKGROUND

Postradiotherapy carotid vasculopathy is a clinically relevant complication in patients with head and neck cancer receiving radiotherapy. In this study, we investigated the factors associated with the development and progression of carotid artery stenosis (CAS) in such patients.

METHODS

Patients who received radiotherapy for head and neck cancers between October 2011 and May 2019 at a medical center in Taiwan were eligible for inclusion in this study. This study included patients who underwent two consecutive carotid duplex examinations within an interval of 1 to 3 years. The factors associated with ≥50% CAS at baseline and follow-up were analyzed.

RESULTS

In total, 694 patients (mean age, 57.8 ± 9.9 years; men, 75.2%; nasopharyngeal cancer, 73.3%) were included. The mean interval between radiotherapy and carotid duplex examination was 9.9 ± 5.9 years. At baseline, 103 patients had ≥50% CAS, which was significantly associated with tobacco smoking, hypercholesterolemia, and a prolonged interval between radiotherapy and carotid duplex examination. A total of 586 patients did not have CAS at baseline; of them, 68 developed ≥50% CAS during follow-up. Hypertension and hypercholesterolemia were identified as independent risk factors for CAS progression.

CONCLUSION

Modifiable vascular risk factors, such as hypertension and hypercholesterolemia, appear to be significantly associated with the rapid progression of postradiotherapy CAS in patients with head and neck cancer.

The emerging role of positron emission tomography (PET) in the management of photon radiotherapy-induced vasculitis in head and neck cancer patients

Purpose

While radiotherapy (RT) for head and neck cancer (HNC) has made recent strides, RT-induced vasculitis continues to adversely affect long-term patient outcomes. Guidelines for managing this complication remain scarce, supporting the need for a sensitive imaging modality in post-treatment evaluations. In this review, we discuss the current literature regarding 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and 18F-sodium fluoride (NaF-PET) in evaluating RT-induced vasculitis in HNC patients, highlighting several arenas of evolving clinical significance: (1) early recognition and standardized evaluation of RT-induced vasculitis, and (2) potential for a multifaceted diagnostic tool to stratify cardiovascular risk in HNC patients.

Methods

Numerous databases, including, but not limited to, Google Scholar and PubMed, were utilized to compile a body of literature regarding PET imaging of RT-induced vasculitis in HNC and related malignancies.

Results

Multiple studies have established the clinical capabilities of FDG-PET/computed tomography (FDG-PET/CT) for detection and management of RT-induced vasculitis in HNC patients, while NaF-PET/CT remains under investigation. Inflammatory vascular stages may be best analyzed by FDG-PET/CT, while vascular microcalcification and atherosclerotic disease may be supplementally assessed by the unique properties of NaF-PET/CT. With these modalities detecting primary stages of more detrimental vascular complications, PET imaging may carry several advantages over conventional, structural techniques.

Conclusion

FDG-PET/CT and NaF-PET/CT hold significant potential as preliminary diagnostic tools in monitoring early inflammation and atherosclerotic plaque development, warranting further research and attention. Applying these techniques in this context may foster proactive and consistent assessments of RT-induced vasculitis in HNC patients, mitigating potential cardiovascular risks through better-informed treatment decisions.

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.

Dexamethasone is Associated With a Lower Risk of the Progression of Thoracic Aortic Calcification in Breast Cancer Survivors

Background and Purpose: Breast cancer survivors have an increased cardiovascular risk, and vascular calcification is the pathological basis of cardiovascular disease. Some factors that affect the progression of thoracic aortic calcification (TAC) in survivors are unclear, and this study aims to explore the relationship between dexamethasone or radiotherapy and the progression of TAC in survivors.

Materials and Methods: This study included 189 female patients with breast cancer, and they were divided into the progression and non-progression TAC groups. Radiation or dexamethasone doses, and related laboratory parameters were collected.

Results: The cumulative dose of dexamethasone was higher [40 (10–180) mg versus 180 (80–270) mg, p < 0.001], and the cycle was longer [4 (1–6) cycles versus 6 (4–8) cycles, p < 0.001] in the non-progression TAC group. The cumulative dose (r = −0.303, p < 0.001) and cycle (r = −0.357, p < 0.001) of dexamethasone were negatively correlated with the level of increased TAC Agatston scores in survivors. Logistic regression analysis showed that dexamethasone was a protective factor for the progression of TAC (p = 0.029, odds ratio = 0.263, 95% confidence interval = 0.08–0.872). However, there wasn’t significant relationship between radiotherapy, radiation dose, follow-up time and the progression of TAC (all p > 0.05). In addition, aorta volume was positively correlated with the level of increased TAC Agatston scores in intensity modulated radiation therapy (r = 0.460, p < 0.001).

Conclusion: Dexamethasone is associated with a lower risk of the progression of TAC in breast cancer survivors, and there’s no correlation between radiotherapy and progression of TAC, but the aorta volume may be a predictor of the severity of progression of TAC.

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.

Cardiovascular Manifestations From Therapeutic Radiation: A Multidisciplinary Expert Consensus Statement From the International Cardio-Oncology Society

Radiation therapy is a cornerstone of cancer therapy, with >50% of patients undergoing therapeutic radiation. As a result of widespread use and improved survival, there is increasing focus on the potential long-term effects of ionizing radiation, especially cardiovascular toxicity. Radiation therapy can lead to atherosclerosis of the vasculature as well as valvular, myocardial, and pericardial dysfunction. We present a consensus statement from the International Cardio-Oncology Society based on general principles of radiotherapy delivery and cardiovascular risk assessment and risk mitigation in this population. Anatomical-based recommendations for cardiovascular management and follow-up are provided, and a priority is given to the early detection of atherosclerotic vascular disease on imaging to help guide preventive therapy. Unique management considerations in radiation-induced cardiovascular disease are also discussed. Recommendations are based on the most current literature and represent a unanimous consensus by the multidisciplinary expert panel.

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Radiation therapy leads to short- and long-term cardiovascular adverse effects of the vasculature and the heart, including valvular, myocardial, and pericardial disease.

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Computed tomography scans conducted for radiation planning or cancer staging provide an available opportunity to detect asymptomatic atherosclerosis and direct preventive therapies.

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Additional practical screening recommendations for cardiovascular disease based on anatomical exposure are provided.

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There are unique considerations in the management of radiation-induced cardiovascular disease; contemporary percutaneous treatment is often preferred over surgical options.

The Treatment of Capsular Contracture Around Breast Implants Induced by Fractionated Irradiation: The Collagenase of the Bacterium Clostridium Histolyticum as a Novel Therapeutic Approach

BACKGROUND

Irradiation therapy limits the utilization of silicone implants for breast reconstruction due to a significant risk for capsular contracture. The injection of the collagenase of the bacterium Clostridium histolyticum (CCH) might trivialize this risk by providing a minimal-invasive treatment option by capsular contracture degradation. However, efficacy in degrading breast implant capsules induced by fractionated irradiation remains unclear.

METHODS

Twenty-four rats in three groups received miniature silicone implants in a submuscular pocket. After 3D dose calculation and treatment field definition, rats of two groups underwent fractionated radiotherapy (6 × 8 Gy) using a linear accelerator. A third group served as control. On day 120, one irradiated group received injections of 0.3 mg/ml collagenase. Administration of plain solvent solution served as control in the two other groups. Outcome parameters included CT-imaging, histology, vessel wall analysis, immunohistochemistry, chemical collagen quantification and gene expression analysis.

RESULTS

Fractioned irradiation leads to a significant increase in collagen deposition around silicone implants with higher capsule thickness and collagen density when comparing all groups. Additionally, significant alterations of collagen fiber deposition were evident. Vessel wall thickness was significantly increased after radiotherapy. The injection of collagenase led to a significant reduction of capsule thickness, collagen density and content. However, the collagenase application induced a significant overexpression of TGFβ1. No side effects were monitored.

CONCLUSIONS

The CCH proved to be a safe and effective approach to degrade capsule tissue induced by fractionated irradiation in an animal model. This may pave its way for clinical application in implant-based breast reconstruction patients.

LEVEL OF EVIDENCE

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Therapeutic alternatives in the management of osteoradionecrosis of the jaws. Systematic review

Background

to systematically review the literature, comparing the healing of osteoradionecrosis (ORN) among the therapeutic alternatives: surgical, pharmacological and combined.

Material and Methods

The review was organized according to the PRISMA protocol with regards to the following PICO question: patients with ORN of the jaws (P=Patient); all interventions reported (I = intervention); between all therapies (C=Comparison); healing of lesions (O=outcome).

Results

Surgical treatment was the most common choice (46.3%) followed by pharmacological treatment, exclusively (25.9%) or combined (26.9%). Treatment exclusively by surgical intervention seems to be most effective option, with 51.2% of the lesions healed, OR for healing of 5.7 (CI95% 1.9-16.9, p=0.002). Only 1 case (0.9%) corresponded to low level laser therapy.

Conclusions

It seems clear that early intervention with conservative surgical combined with pharmacological methods improves the prognosis of ORN.

Key words:Osteoradionecrosis, radiotherapy bone necrosis, hyperbaric oxygen, pentoxifylline, teriparatide, low level laser therapy.

Risk of ischaemic cerebrovascular events in head and neck cancer patients is associated with carotid artery radiation dose

BACKGROUND AND PURPOSE

Radiotherapy in the head and neck area may cause vascular damage to the carotid arteries, increasing the risk of anterior circulation ischaemic cerebrovascular events (ICVEs). However, limited data exists on the relationship between radiation dose to the carotid arteries and risk of ICVE. The purpose of this study was therefore to determine the relationship between radiation dose to the carotid arteries and anterior circulation ICVE risk.

MATERIALS AND METHODS

A retrospective analysis of a prospective study cohort of 750 head and neck cancer patients treated with definitive (chemo)radiotherapy was performed. Carotid arteries were delineated, and dose-volume parameters of the treatment plans were calculated. ICVEs were scored prospectively and checked retrospectively by analysing all patient records. Cox proportional hazards analysis was performed to analyse the dose-effect relationships.

RESULTS

The median follow-up period was 3.4 years, 27 patients experienced an ICVE and the 5-year cumulative risk was 4.6%. ICVE risk was significantly associated with dose to the carotid arteries. Multivariable analysis showed that the absolute volume (cm³) of the carotid arteries that received at least a radiation dose of 10 Gy was the most important prognostic factor for ICVE (HR = 1.11, AUC = 0.68, p < 0.001).

CONCLUSION

This is the first large prospective cohort study that demonstrates an independent dose-effect relationship between radiation dose to the carotid arteries and the risk of ICVE. These findings may be used to identify patients at risk for ICVE after radiotherapy who may benefit from primary or secondary preventive measures.

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.

Innominate to contralateral brachial artery bypass via ministernotomy with anatomic tunneling for critical ischemia of the left upper extremity

OBJECTIVES

Scarring from prior bypass surgery and irradiation may compromise revascularization options in critical ischemia due to underlying occlusive disease. Occlusive disease of the axillo-brachial artery is particularly difficult to revascularize under such hostile conditions.

METHOD

We present a case of a 58-year-old woman presenting with a painful, pulseless, and cool left upper extremity. The patient had a known history of left upper extremity occlusive disease which was managed by subclavian-axillary artery stenting with re-occlusion and subsequent extra-anatomic left carotid-to-proximal brachial artery prosthetic bypass, which was complicated by stroke. The patient had a history of left mastectomy, axillary node dissection, and external beam radiation therapy. When considering revascularization options, the combination of post-radiation changes and scarring of the conventional operative zones for revascularization posed a high risk for complications. We describe a novel approach for such revascularization, where the inflow source was the terminal brachiocephalic artery, outflow to the upper left brachial artery, with anatomic intrathoracic-to-axillary tunneling through the thoracic outlet after verifying the lack of dynamic extrinsic compression at that level.

RESULT

The procedure resulted in resolution of the symptoms and the patient continued to do well 2 years later.

CONCLUSION

This case shows that anatomic tunneling through the thoracic outlet can be a viable option for upper extremity revascularization when hostile conditions preclude other anatomic tunneling routes or extra-anatomic options.

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.

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.