Bilateral internal carotid artery disease secondary to cervical radiation. A case report

Vascular events from carotid artery atherosclerosis after radiation therapy for laryngeal and hypopharyngeal cancer: the incidence and risk factors

In this retrospective cohort study, we evaluated the incidence of vascular events from carotid artery atherosclerosis after radiotherapy indication for laryngeal and hypopharyngeal cancer. From January 2007 to December 2016, we investigated 111 laryngeal/hypopharyngeal cancer patients who underwent curative radiotherapy and were followed up for ≥1 year (median follow-up duration, 60 months). We evaluated the incidence of vascular events from carotid artery atherosclerosis, defined as a transient ischemic attack or an atherothrombotic cerebral infarction, or from undergoing treatment such as carotid artery stenting for carotid artery stenosis. The median radiation dose was 66 Gy (range, 60–74); 48 patients (43.2%) received concurrent chemotherapy. The 5-year overall survival was 86.2%. Six patients required treatment for carotid artery disease. Carotid stenting was performed in three patients with carotid artery stenosis; three patients developed atherosclerotic cerebral infarction and received medical treatment, with a median of 51.7 months (range, 0.3–78.3) after radiotherapy initiation. The vascular event occurrence rate was 5.4% within 5 years and 10.7% within 8 years. In the univariate analysis, dyslipidemia, diabetes mellitus, and carotid calcification were significant factors for event occurrence. Because three out of six cases occurred out of the irradiated field, no carotid artery or carotid bulb dosimetric parameters showed significant correlation. As laryngeal/hypopharyngeal cancer patients, particularly with complications including dyslipidemia and diabetes mellitus, are at a high risk of carotid artery stenosis after radiotherapy, long-term carotid artery evaluation is necessary. Early intervention by stroke specialists can reduce the risk of fatal cerebral infarction.

Ocular ischemic syndrome secondary to carotid artery occlusion as a late complication of radiotherapy of nasopharyngeal carcinoma

A 39-year-old Chinese man developed ocular ischemic syndrome (OIS) in both eyes 14 years after radiation therapy for nasopharyngeal squamous cell carcinoma. Digital subtraction angiography disclosed occlusion of common carotid arteries and stenosis of both vertebral arteries. Following stenting of the vertebral arteries, visual function improved and ophthalmoscopic abnormalities of OIS regressed in the right eye. Radiation therapy of the head and neck has a relatively high likelihood of causing vascular stenosis. However, we believe this to be the first reported case of OIS following radiotherapy for nasopharyngeal carcinoma.

Detection of radiation-accelerated atherosclerosis of the carotid artery by panoramic radiography

BACKGROUND

The authors review the pathophysiology, epidemiology, course of disease, dental findings and dental treatment of patients who developed atherosclerosis of the carotid artery after having received therapeutic radiation to the neck for squamous-cell carcinoma of the oral cavity, pharynx or larynx; salivary gland tumors; and lymphomas involving the cervical lymph nodes.

TYPE OF STUDIES REVIEWED

The authors conducted a MEDLINE search for 1997 through 2002 using the key terms "radiation therapy," "carotid artery" "atherosclerosis," "cancer" and "dentistry." The articles selected for further review included those published in English in peer-reviewed journals, with preference given to articles reporting randomized, controlled trials.

RESULTS

Recent advances in the delivery of radiation therapy to malignancies of the head and neck have resulted in the prolonged survival of increasing numbers of patients. However, the therapy has been implicated as causing atherosclerotic lesions in the cervical component of the carotid artery, which predisposes patients to an increased risk of developing stroke. Panoramic radiography can identify some of these lesions before they can cause a stroke. Radiation-induced atherosclerosis is common, with approximately 40 percent of patients developing hemodynamically significant carotid artery plaques within 10 years of having received irradiation.

CLINICAL IMPLICATIONS

Dentists treating patients who have received therapeutic radiation to the neck should examine the patients' panoramic radiographs for evidence of atheromalike calcifications, which appear 1.5 to 2.5 centimeters posterior and inferior to the angle of the mandible. Patients with evidence of such lesions should be referred to their physician for an ultrasound examination of their carotid arteries.

Carotid intima-media thickness in patients with head and neck irradiation for the treatment of nasopharyngeal carcinoma

AIM

Intima-media thickness (IMT) has been shown to be useful in the evaluation and monitoring of carotid artery atherosclerosis in patients at risk of cardiovascular events. In this study, we aimed to examine the IMT in patients with nasopharyngeal carcinoma (NPC) who received irradiation to the carotid arteries during radiotherapy, and compared them with a control group.

MATERIALS AND METHODS

Fifty-one NPC patients (aged between 39 and 69 years) and a group of 51 age-and sex-matched controls were studied by ultrasound. The IMT at the far wall of the common carotid artery was measured three times and the average value taken in each subject. The IMT of both groups were compared. Risk factors for IMT thickness, including hypertension, smoking, hyperglycaemia, hypercholesterolaemia, history of cerebrovascular accidents and cardiovascular disease, were also studied.

RESULTS

The mean carotid IMT of patients in the NPC group (2.2+/-1.5 mm) was statistically greater than that in normal controls (0.7+/-0.15 mm) (P < 0.05). There was no statistically significant difference between the IMT in the right and left common carotid arteries within each group of patients.

CONCLUSION

The findings suggest that patients with irradiation have increased arterial IMT. As they are asymptomatic the clinical relevance is not clear.

Endovascular repair of radiation-induced bilateral common carotid artery stenosis and pseudoaneurysms: a case report

BACKGROUND

Radiation-induced damage to small and medium-sized vessels has been observed in both animals and humans. Changes may appear in the immediate postradiation period or many years later. In this case, we report an unusual presentation of bilateral radiation-induced carotid artery stenoses associated with pseudoaneurysms, and a previously unreported application of a recently established treatment.

CASE DESCRIPTION

A 72-year-old African-American male presented with recurrent right hemispheric transient ischemic attacks (TIA) and neck pain. Thirteen years previously, the patient had received radiation therapy for laryngeal carcinoma. Diagnostic carotid angiography demonstrated moderate radiation-induced bilateral carotid artery stenosis and associated common carotid pseudoaneurysms. The patient was treated with bilateral endovascular stents and electrolytically detachable coils in staged procedures. At his most recent follow-up, there is no evidence of re-stenosis and the patient remains asymptomatic.

CONCLUSIONS

This case illustrates a novel and successful treatment for the endovascular repair of post-radiation bilateral carotid artery stenosis and pseudoaneurysms. In our practice, we have seen three such cases of radiation-induced vasculopathy. Therefore, patients with a previous history of radiation therapy for head and neck neoplasms merit cautious monitoring and judicious use of stents and secondary coils, when necessary.

Detection of radiation-induced cervical atheromas by panoramic radiography

Therapeutic irradiation of the neck is frequently used to treat patients with head and neck carcinoma. The irradiation, however, has been implicated as the cause of cervical carotid artery atherosclerotic lesions and subsequent stroke. Panoramic radiography previously shown capable of demonstrating isolated lesions was used to assess their development over time. Individuals with a pre-irradiation radiograph free of atheromas were enrolled for study. The prevalence rate of atheroma formation on post-irradiation (bilateral portals at >/=45 Gy) radiographs obtained at an interval of >/=36 months was determined. A control group of non-irradiated patients having similar risk factors for head and neck carcinoma and atherosclerosis and having an initial radiograph free of atheroma formation were likewise enrolled for study. The prevalence rate of atheroma formation on a second radiograph obtained from these individuals at an interval of >/=36 months was determined. The study population consisted of 17 patients, with a mean age of 56.5 (range 21.5-77.8) years who received a mean therapeutic irradiation dose of 53.2 Gy (range 45-71) to each side of their neck. The prevalence rate of atheromas manifested on the post-irradiation radiographs was 53%. These radiographs were obtained, on average, 69.7 (range 37-133) months after completion of radiation therapy. The prevalence rate of atheromas manifested on the second radiograph of patients in the control group was 5.9%. These radiographs were obtained, on average, 53.5 (range 52-55) months after the first. The difference in prevalence rates was statistically significant (p=0.0003). Individuals who have received therapeutic irradiation to the neck are more likely to develop carotid artery atheromas after treatment than are risk-matched control patients who have not been irradiated. These lesions can be detected by panoramic radiography.

Detection of radiation-induced, accelerated atherosclerosis in patients with osteoradionecrosis by panoramic radiography

PURPOSE

Osteoradionecrosis (ORN) of the mandible has long been considered the most destructive complication of head and neck irradiation. Recently, therapeutic irradiation has been implicated as the cause of induced/accelerated atherosclerosis of the cervical carotid artery and subsequent stroke. Panoramic radiography, previously shown to be capable of identifying carotid artery atherosclerosis in nonirradiated individuals, was used to assess the carotid vasculature of patients being treated for ORN.

PATIENTS AND METHODS

The panoramic radiographs of 61 men (mean age, 60.5 years; range, 41 to 77 years) who received therapeutic irradiation to the neck 36 months or more previously were assessed for the presence of carotid artery atherosclerotic lesions. Sixty-one control subjects who never received therapeutic irradiation, but who were similarly susceptible to atherosclerosis by virtue of age, were assessed in a like manner.

RESULTS

The irradiated individuals sustained a dose of 40 to 72 Gy to the area of the carotid bifurcation. Seventeen individuals (27.9%) with an irradiation dosage to the carotid bifurcation that averaged 59.2 Gy had a panoramic radiograph with a carotid atheroma (11 with unilateral lesions and six with bilateral lesions). The radiographs of the control subjects showed that three individuals (4.9%) had calcified carotid lesions. The mean age of these subjects was 66.1 years; two had unilateral lesions, and one had bilateral lesions. The difference in the proportion of individuals with ORN who manifested carotid artery atherosclerosis on their panoramic radiographs was statistically significant (P = .001) when compared with the nonirradiated control subjects. The lesions seen in both populations had a similar morphologic appearance and were radiographically located within the soft tissues of the neck 1.5 to 4.0 cm inferior-posterior to the angle of the mandible.

CONCLUSIONS

Individuals with radiation doses sufficient to cause osteoradionecrosis of the mandible are at significantly higher risk of developing carotid artery atherosclerotic lesions than age-matched, nonirradiated controls.

The role of panoramic radiography in determining an increased risk of cervical atheromas in patients treated with therapeutic irradiation

PURPOSE

Therapeutic irradiation of the neck is a common component of treatment for those with carcinoma of the oral cavity, pharynx, and larynx. Such irradiation, however, has been implicated as the cause of accelerated atherosclerosis of the cervical carotid artery and subsequent stroke. Panoramic radiography, previously shown to be capable of identifying carotid artery atherosclerosis in non-irradiated individuals, was used to assess the carotid vasculature of patients who had been treated for cancer with therapeutic irradiation.

METHODS

The panoramic radiographs of 33 male subjects who had received therapeutic irradiation (> or = 50 Gy) to the neck 30 or more months previously were assessed for the presence of calcified carotid artery atherosclerotic lesions. Age-matched controls, similarly liable for oropharyngeal malignancy and atherosclerosis by virtue of their medical and habitual risk factors (hypertension, smoking, obesity) were assessed in a like manner.

RESULTS

The panoramic radiographs of the irradiation-treated subjects (age range, 32 to 84 years; mean age, 66.1 years) showed that 21% (7 of 33 subjects) had calcified atherosclerotic lesions. The mean age of these seven subjects was 64.6 years; four had unilateral lesions and three had bilateral lesions. The radiographs of the control subjects showed that 4.7% (5 of 107 subjects) had calcified atherosclerotic lesions. The mean age of these five subjects was 67; three had unilateral lesions and two had bilateral lesions. The lesions seen in the two populations had similar morphologic appearances. The discrete radiopaque calcifications were located within the soft tissues of the neck, approximately 2.5 cm inferior-posterior to the angle of the mandible.

CONCLUSIONS

Subjects who had received therapeutic irradiation of the neck had a statistically higher risk (p = 0.007, according to Fisher's Exact Test) of the development of calcified carotid artery atherosclerotic lesions than age-matched, risk-matched, non-irradiated control subjects. These lesions can be detected on routine panoramic radiographs.