Incidence of carotid stenosis in nasopharyngeal carcinoma patients after radiotherapy

BACKGROUND. Radiation-induced carotid stenosis in patients with head and ne ck tumors can cause significant mortality and morbidity. This study examine d the incidence of stenosis in the extracranial carotid arteries of nasopha ryngeal carcinoma patients after radiotherapy. METHODS. The extracranial carotid arteries of 71 (53 male and 18 female; me an age of 53.6 years) postradiation patients with nasopharyngeal carcinoma were examined with color Doppler ultrasound. The distribution of the arteri al stenosis and the degree of stenosis were documented. The results were co mpared with the control group, which comprised 51 newly diagnosed nasophary ngeal carcinoma patients (35 male and 16 female, mean age of 48.8 years) be fore radiotherapy. Incidences of risk factors for arterial stenosis such as hypertension, smoking, and hypercholesterolemia also were studied in these two groups. RESULTS. There was no significant difference in the incidence of risk facto rs between the two groups. Arterial stenosis was, however, more common in t he postradiation group than the preradiation group (56 of 71 vs. 11 of 51). The common/internal carotid arteries (CCA/ICA) were most commonly involved (55 of 71 vs. 11 of 51; P < 0.01), followed by the external carotid artery (ECA) (32 of 71 vs. 1 of 51; P < 0.01) and vertebral artery (VA; 5 of 71 v s. 0; P = 0.069). Significant stenosis (> 50% reduction of luminal diameter ) was only found in the postradiation group (21 of 71 in CCA/ICA, 11 of 71 in ECA, 4 of 71 in VA). CONCLUSIONS. This study showed that radiation could cause significant carot id stenosis. Ultrasound examinations for these patients therefore are neces sary for early detection and possible intervention of this late radiation-i nduced complication. (C) 2001 American Cancer Society.