Accelerated carotid artery disease after high-dose head and neck radiotherapy: Is there a role for routine carotid duplex surveillance?

Purpose: High-dose external radiotherapy used in the treatment of head and neck carcinoma has been implicated as a risk factor far accelerated atheros clerotic disease of the carotid arteries. However, how radiotherapy affects atherosclerotic disease is controversial, and little data exist to demonst rate a strong relationship between radiotherapy and progressive carotid dis ease. Methods: We performed a retrospective chart review of 69 patients (all men) who underwent duplex ultrasound scanning examinations for carotid disease between 1993 and 1998. Twenty-three patients had received high-dose radioth erapy for the treatment of head and neck carcinoma within the past 12 years (group 1; mean age, 67.8 years), and 46 patients were randomly selected as age-matched control subjects (group 2; mean age, 68.3 years). The mean rad iation dose was 6060 +/- 182 rads, and the average interval between radioth erapy and ultrasound scanning was 6.5 +/- 1.8 years. There was no significa nt difference between the two groups in the presence of these comorbidities : diabetes mellitus, coronary artery disease, hypertension, tobacco use, hy percholesterolemia, peripheral vascular disease, or stroke. Similarly, ther e was no difference in the indications for the duplex scanning studies. Results: Five of the 23 patients in group 1 (21.7%) were found to have adva nced carotid disease (70% to 99% stenosis); four patients were symptomatic, three patients went on to endarterectomy, and one patient was awaiting sur gery. Two of the 46 patients in the control group (4%) had advanced carotid disease. One patient was symptomatic, and both patients underwent endarter ectomy. A significant difference in the prevalence of advanced disease betw een the two groups was noted (P = .037). Sixteen patients who survived irra diation underwent a second duplex scanning study and had evidence of progre ssive disease with significant increases in peak systolic velocities. Conclusion: High-dose radiotherapy to the head and neck region may be a sig nificant risk factor for accelerated carotid atherosclerotic disease. Routi ne carotid duplex surveillance may be warranted in this high-risk patient p opulation.