Literature reports suggest as high as 77.5% of symptomatic carotid stenosis (on risky regions of common carotid and internal carotid arteries) as compared to 21.6% on the matched control group (consisting of newly diagnosed patients with similar risk factors)18. A retrospective review from Philadelphia on 413 treated patients found RR for stroke of 2, as compared with the general population (matched for risk factors) from the Stockholm database5. Data from the Netherlands suggested risk for stroke as high as 5 times as compared to the matched group without cancer. The analysis was done on patients who received the treatment before 60 yo (the comparison was not made to the general population as these patient are usually smokers and drinkers and are usually at a higher risk to begin with, however XRT increases this already high risk by 5).