Head and neck radiotherapy-induced carotid toxicity: Pathophysiological concepts and clinical syndromes.

This review aims at offering a concise cross-section of head and neck radiotherapy-induced carotid toxicity for pathological concepts to emerge and become part of clinical routine. Radiation-induced carotid toxicities such as atherosclerosis, arterial stiffness and arterioradionecrosis result from radiation dose limitation. Atherosclerosis is related to lesions in the epithelial wall. Such lesions are early radiotherapy-related toxicities and depend on the radiation dose. Atherosclerosis may lead to carotid stenosis and stroke. Arterial stiffness and arterioradionecrosis are late toxicities of the connective tissue that have a low alpha/beta ratio. They are risk factors of pseudoaneurysm and carotid blowout syndrome or stroke in some cases. Because all these pathophysiological mechanisms interfere, post-radiation vascular diseases remain particularly severe and difficult to understand.