CT scanning in children and risk of cancer: what three large-scale studies have demonstrated

That irradiation from diagnostic CT examinations has caused cancers in a small minority of young patients in the past is no longer controversial. Three recent studies from the UK, Australia and the USA have published data supporting a small but real risk of a CT scan in early life being associated with a later risk of malignancy, due solely to the CT scan. The American study showed a temporary increase in the frequency of CT scanning of children with regrettably large variation in radiation dose per scan. Most of the patients in the published studies had their CT examinations over a decade ago, and it is likely in more recent years that widespread reductions in tube current-time product (mAs) have substantially lessened the radiation burden to children from CT. It must be remembered that CT is a very useful clinical test. Whenever CT is justified, the clinical benefit virtually always outweighs the longer term very small risk of malignancy.