Carotid Surgery or Stenting Following Neck Irradiation: Time to Address the Assumptions

Abstract

Magne et al. are to be congratulated for reviewing the outcomes of carotid surgery for their 24 patients with prior neck irradiation,1 adding one of the largest and longest followed case-series reported for such patients. This, and the other 17 case-series quoted by Magne et al. of patients with prior neck irradiation undergoing open carotid surgery2e9 or angioplasty/stenting,9e17 illustrate how these procedures are technically possible with low 30-day procedural stroke/death rates. Considering all 18 case-series, the periprocedural 30-day stroke/death rate was 0% in ten (56%).1,3e6,8,11,12,15,17 However, among these ten case-series, the average sample size was only 16 patients (range 4e28) with a mean followup of approximately 1.6 years (range 1e37 months). By contrast, in the remaining eight case-series, the 30-day perioperative stroke/death rate was >0% (range 1.5e10%). In these, the average sample size was over double, 35 patients (range 10e135), with a mean followup of approximately 2.7 years (range 18e58 months). Small sample sizes, brief followup and publication bias (good operative results more likely reported and published) are important reasons why routine practice procedural risk may be underestimated. It has taken prospective studies of thousands of patients to compare safety of carotid surgery versus stenting in patients without prior neck irradiation. Further, it is clear that procedural results from one centre cannot be assumed equivalent to another. Crucial elements in determining procedural complication rates are; operator experience, procedural technique, quality of vascular disease medical (non-invasive) intervention received, patient risk factor profile and method of followup to identify outcomes. It is also clear that the stroke prevention efficacy of vascular disease medical intervention has improved significantly over recent decades indicating that fewer patients are now likely to benefit from invasive carotid procedures.18e21 As medical intervention improves, invasive carotid procedures need to become more specialised. It is time for all carotid surgery and endovascular services to adopt ongoing audit activities, documenting use of current, optimal vascular disease medical intervention and procedural technique and incorporating independent, prospective identification of outcomes of