Effects of supraclavicular radiotherapy on carotid arteries in breast cancer patients.

PURPOSE: To evaluate the effects of supraclavicular radiotherapy on carotid arteries using Doppler ultrasonography by comparing irradiated and non-irradiated sides within the same patients. METHODS: This retrospective observational study included 50 female patients who had previously undergone supraclavicular radiotherapy for breast cancer. All participants were evaluated using carotid Doppler ultrasonography. The mean interval between completion of radiotherapy and ultrasonographic evaluation was 6.1 ± 2.7 years. Carotid artery diameters, intima-media thickness (IMT), and Doppler parameters (peak systolic velocity [PSV] and end-diastolic velocity [EDV]) were measured on both irradiated (RT+) and non-irradiated (RT-) sides. Correlation analyses between time since radiotherapy and vascular parameters were performed. RESULTS: IMT values were significantly higher on the irradiated side for both the common carotid artery (CCA) and internal carotid artery (ICA) (p = 0.001 for both). CCA diameters were significantly increased on the irradiated side, whereas ICA diameters showed no significant differences. Doppler parameters (PSV and EDV) did not differ significantly between irradiated and non-irradiated sides (p > 0.05 for all). No significant correlation was observed between time since radiotherapy and IMT values. CONCLUSION: Supraclavicular radiotherapy is associated with significant structural changes in carotid arteries, particularly increased IMT, while hemodynamic flow parameters remain preserved. IMT measurement may serve as a useful non-invasive tool for early detection of radiation-induced vascular injury.