Projected Cancer Risks From Computed Tomographic Scans Performed in the United States in 2007

Abstract

The use of computed tomographic (CT) scans in the United States (US) has increased more than 3-fold since 1993 to approximately 70 million scans annually.¹ While CT scans can provide great medical benefits, there is concern about potential future cancer risks because they involve much higher radiation doses than conventional diagnostic x-rays.¹ The risks to individuals are likely to be small, but because of the large number of persons exposed annually, even small risks could translate into a considerable number of future cancers. To fully evaluate the long-term cancer risks from CT scans directly would require very large-scale studies with lifelong follow-up.² A more timely risk assessment can be obtained using risk projection models.³