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Risk Assessment: Computed Tomography (CT) Scans and Screening Examinations

The number of CT scans performed in the United States has increased to more than 70 million per year. CT scans of young patients are of particular concern because, in comparison with adults, children are exposed to higher doses, are generally more sensitive to the carcinogenic effects of radiation, and have a longer life-span to express radiation-related cancers. In a study of 180,000 children, DCEG investigators found increased risks of leukemia and brain tumors after childhood CT scans following linear dose-response relationships for leukemia and brain tumors that were broadly consistent with the risks observed in the Japanese atomic bomb survivors. The absolute risk estimates were small. Work is continuing in the United Kingdom and other cohorts to address further questions about the relationship between pediatric CT scans and subsequent cancer risk.

For more information, contact Lindsay Morton.

Radiation Epidemiology Branch - Research Areas