Reducing unnecessary or high-dose CT scans in pediatric scans could lower the number of future radiation-induced cancers, according to a retrospective study published online June 10 in JAMA Pediatrics.
The study also determined that the number of CT scans performed on children younger than 14 skyrocketed in the decade from 1996 to 2005. While the researchers--Diana L. Miglioretti, Ph.D., of the University of California, Davis, and colleagues--found that CT use stabilized in 2006 and 2007, and has declined since then, that period of increased pediatric CT scanning elevated radiation-induced cancer risks in the younger patients.
Miglioretti and colleagues studied pediatric CT imaging trends in six different U.S. healthcare systems, and measured the rate of CT scan use, as well as the dose of ionizing radiation for these scans. Scans involved the head, abdomen/pelvis, chest and spine.
The study concluded that the risk of radiation-induced solid cancers was highest for those patients undergoing CTs of the abdomen and pelvis, which also had the most dramatic increase in use. Breast, thyroid and lung cancers and leukemia account for 68 percent of projected cancers in exposed girls, while brain, lung and colon cancer and leukemia account for 51 percent of future cancers in boys.
The researchers also determined that the 4 million CT scans conducted of the most commonly imaged organs in children could result in approximately 4,870 future cancers.
"There are potential harms from CT, meaning that there is a cancer risk, albeit very small in individual children, so it's important to reduce this risk in two ways," Miglioretti said in an announcement. "The first is to only do a CT when it's medically necessary, and use alternative imaging when possible. The second is to dose CT appropriately for children."
Reducing the highest 25 percent of radiation doses could prevent 43 percent of these future cancers, Miglioretti said, while eliminating unnecessary or inappropriate imaging could eliminate 62 percent.
The American College of Radiology released a statement "urging parents not to delay or forego needed medical imaging care for their children based solely" on the study.
"Parents should certainly discuss such potential risk with their physician, but this appropriate concern should not translate into refusal of necessary and potentially life-saving care," Marta Hernanz-Schulman, M.D., chair of the American College of Radiology Pediatric Imaging Commission, said in the statement.