The role of radiotherapy in the carotid stenosis

Abstract

OBJECTIVE: Cervical radiation for head and neck cancer has been associated with an increased incidence of carotid arterial stenosis. Modern radiation therapy delivers higher doses with increasing long-term survival. In our study 50 patients with head and neck malignancies treated with radiotherapy are analized with colour Doppler ultrasonographic scanning of the carotid arteries. These patients were compared with a population of asymptomatic historical controls (40) These findings suggest that radiation has an adverse effect on large vessels. Colour Doppler follow-up may be indicated for patients receiving head and neck radiation therapy.

METHODS: 50-70 Gy is the local dose that all patients received. during a period of about 8 weeks. The ecodoppler scan of carotid arteries was performed in all patients with estimation of Common and internal carotid artery’s intimal medial thickness (IMT). Stenosis grade were divided into low (0-30%), moderate (31-49 %) and severe (= >50%). In add we considered ematochimics and flogosys parameters. Patients recruited from a hospital Radiation-oncology-surgery department from April 2007 to September 2011, 90 consecutive head and neck cancer patients were enrolled in this study. 50 of these patients had previously undergone RT (RT group) and 40 had no RT (control group). All patients were screened with bilateral carotid arterial duplex ultrasonography. We defined disease as “normal or mild” if the carotid stenosis was <50%, and “significant” if >50%. The relationship between standard demographic risk factors and screening outcomes was then analyzed.

RESULTS: We found that severe carotid stenosis (= >50% ) was higher (41%) in patients who underwent to radiotherapy than in control group. The Eco Doppler examination demonstrated that the most affected site was Internal Carotid Arthery ‘s fork . There were no differences in age or gender between the two groups. The RT group had a significantly higher plaque score than the non-irradiated group. Bilateral plaque score was significantly correlated with age, hyperlipidemia, and RT. This analysis showed that in RT patients > 50 years old, age was inversely correlated with plaque score; however, in RT patients<or= 41=  years old, age was positively correlated with plaque score.

CONCLUSIONS: Literature evidences about this subject are few and similar to ours. Moritz et all found a severe carotid stenosis in 30% of irradiated and 5.6% in the control group. Lam found carotid stenosis in 78.9% of irradiated and 21.6% in the other group. We can conclude that radiotherapy is able to induce atherosclerotic lesions only in sites included in radiation field. Should be important to perform pre and post radiotherapy Carotid Arthery Ecodoppler of patients who are going to undergo cervical radiotherapy The prevalence of carotid arterial disease in patients with prior cervical radiation therapy is clinically significant and warrants aggressive screening as part of routine preradiation and postradiation care. Focused screening of this high-risk population may be cost effective and medically beneficial in terms of risk factor modification and stroke prevention.