Modeling study of projected lifetime cancer risks from current computed tomography imaging

Approximately 93 million computed tomography (CT) examinations are performed on 62 million patients annually in the United States, and ionizing radiation from CT is a known carcinogen. A modeling study using the National Research Council’s Biological Effects of Ionizing Radiation VII models projected that this use of CT will result in approximately 103,000 future cancers over the lifetime of the exposed patients. Although the per-examination cancer risk was higher in children, higher CT utilization among adults accounted for the majority of the projected cancers. The authors conclude that these findings suggest that if current radiation dosing and utilization practices continue, CT-associated cancers could eventually account for 5% of all new cancer diagnoses annually.