Incidence and risk factors of significant carotid artery stenosis in asymptomatic survivors of head and neck cancer after radiotherapy.

BACKGROUND: The incidence and risk factors of carotid artery stenosis in asymptomatic patients after head and neck radiation therapy (RT) are unknown.

METHODS: This retrospective study reviewed asymptomatic patients treated with RT for head and neck cancer from 2000 to 2009 who underwent screening carotid ultrasound.

RESULTS: Two hundred twenty-four patients were included, the majority of whom had stage III to IV disease and received cisplatin-based chemotherapy. Median time from RT completion to last carotid ultrasound was 3 years. Actuarial rate of carotid artery stenosis at 4 years was 14% (95% confidence interval [CI], 4% to 22%). Multivariate analysis revealed that carotid artery stenosis was associated with Framingham risk factors (hazard ratio [HR], 1.6 per factor; 95% CI, 1.2-2.2; p = .003). Among 135 patients treated with intensity-modulated radiation therapy (IMRT), the HR for carotid artery stenosis was 1.4 for every 10 Gy increase in mean RT dose to the carotid bulb plus 2 cm (95% CI, 0.8-2.4; p = .35).

CONCLUSION: Prevention and screening programs should be considered for head and neck cancer survivors given the high risk of carotid artery stenosis.