One in 1,000 to 500 Chance of Cancer from Childhood CT Scan

The first study to assess directly the risk of cancer after CT scans in childhood found a clear dose-response relationship for both leukemia and brain tumors: risk increased with increasing cumulative radiation dose. For a cumulative dose of between 50 and 60 milligray or mGy (mGy is a unit of estimated absorbed dose of ionizing radiation) to the head, the investigators reported a threefold increase in the risk of brain tumors; the same dose to bone marrow (the part of the body responsible fo...

 1.9 Cases of Leukemia per 10,000 CT Scans in Children

In the breakdown of results, the study authors from Group Health Research Institute and University of California, Davis note that the risk of developing leukemia was highest from head scans for kids under age 5 with a rate of 1.9 cases per 10,000 CT scans. Younger children and girls seemed more susceptible to solid cancers than older kids and boys. Every 300 to 390 scans of a girl’s abdomen or pelvis was associated with the development of one solid cancer. The study estimates that 4,870 fut...