Is a history of radiation therapy a contraindication for carotid surgery?

Advances in surgical and medical oncology have seen a significant increase in survival of patients suffering from head and neck malignancies. Many of these patients are treated with radiotherapy to the neck, including the cervical carotid artery. Cervical irradiation (CI) may induce carotid stenosis. Prior CI in association with carotid artery stenosis poses potential challenges, when revascularization is considered. As the focus of radiotherapy determines the level of the resultant obstruction it may be in a location that is difficult to reach surgically. Also scar tissue from CI may increase the risk of cranial nerve injury. Carotid angioplasty and stenting (CAS) may be an alternative for CEA in post CI cases. This manuscript aims to derive a treatment algorithm for post CI stenosis from the available literature, answering three questions: 1) do symptomatic post CI stenoses require revascularization?; 2) Do asymptomatic post CI stenoses require revascularization?; 3) What is the preferred revascularization modality? The answers to those questions are the following: 1) as several studies have shown the increased likelihood of stenosis after CI and its potential for embolic events, symptomatic stenosis should be treated; 2) patients after CI have a much greater chance of serious events from their malignancies than from their carotid disease, therefore most asymptomatic stenoses probably do not warrant revascularization; 3) CEA post CI carries less peri procedural risk than previously supposed and CAS is hampered by increased restenosis rates, so CEA should be the preferred treatment if feasible. An individual patient tailored approach for post CI carotid stenosis is warranted, the guideline being: "If symptomatic: revascularize; if possible: operate; if not: consider stenting".