Authors´ conclusions: exposure to a single CT scan was not associated with an increased risk of leukemia, lymphoma, or intracranial tumour. It was observed that from the fourth exposure or more, and especially in children with younger ages, an increased risk of cancer. As a conclusion of the study, the prudently need to indicate CT scans in the pediatric population is highlighted.
Reviewers´ commentary: children are more susceptible to damage induced by ionizing radiation than adults, but there are few studies on cancer risk after radiation exposure in children. In this case-control study on younger than 25 years, more incidence of intracranial tumours, leukemia and lymphoma were observed after exposition to more than one CT scan before 18 years.