Premature carotid artery disease in pediatric cancer survivors treated with neck irradiation

BACKGROUND: While carotid artery disease and strokes have been documented in adult cancer patients treated with neck irradiation, little information is available on pediatric patients. The purpose of this study is to determine if carotid disease is more prevalent among pediatric cancer survivors treated with neck irradiation than among healthy controls. PROCEDURE: Thirty pediatric cancer survivors who received neck irradiation (2,000-6,660 cGy) and 30 healthy subjects underwent bilateral carotid ultrasounds. Study outcome measures were common carotid intima-media thickness (IMT) and plaque (present or absent). Multivariate methods were used to compare cases and controls and to identify risk factors related to carotid disease in childhood cancer survivors. RESULTS: IMT was greater for cancer survivors than controls (0.46 mm (SD 0.12) vs. 0.41 mm (SD 0.06), P < 0.001). Plaque was present in 18% of irradiated vessels and 2% of non-irradiated vessels (P < 0.01). Among cancer survivors, IMT was positively associated with female gender (P < 0.05), non-white ethnicity (P < 0.01), positive family history of stroke/heart attack (P < 0.05), BMI (P < 0.001), total cholesterol (P < 0.01), cancer relapse (P < 0.001), and years off treatment (P < 0.0001). Plaque was positively associated with relapse (P < 0.05) and C-reactive protein (P < 0.01). There was no significant relationship between radiation dose at levels >or=2,000 cGy and IMT or plaque. CONCLUSIONS: Carotid artery disease was more prevalent among cancer survivors treated with neck irradiation than among controls. Due to the high risk of stroke associated with advanced carotid disease, larger prospective studies are needed to better define disease risk in these long-term survivors.