Parents should not be panicked by recent news reports of children at risk of cancer caused by computed tomography (CAT) scans, say experts, including the doctor who led one of the widely reported studies picked up by news organizations. Instead, they say, parents should concentrate on the issue at the center of the research: whether adult-appropriate levels of radiation are being given incorrectly to children.
The first study both reports appeared in the February issue of the American Journal of Roentgenology tried to quantify the risk from pediatric CAT scans. CAT is a high-tech tool that uses multiple X-ray images to create 3-D views of a patient's internal organs. CAT scans clearly help doctors diagnose and treat disease, but as two recent studies suggest, the radiation dose they deliver also poses risks, especially for children and particularly since the use of CAT scans to diagnose appendicitis, for example, has become so widespread.
The research team, led by Dr. David Brenner of Columbia University, estimates that of the 1.6 million children who get CAT scans to the head and abdomen each year, about 1,500 will eventually die from a cancer induced by the radiation of those scans. Children are especially vulnerable because their rapidly dividing cells are more susceptible to radiation damage and also because they will live long enough for even slow-growing cancers to take their toll. Perhaps the biggest risk factor, investigated by the second study, led by Dr. Lane Donnelly at Cincinnati's Children's Hospital, is that too many CAT scanners are giving kids adult-size doses of X rays, often several times higher than necessary.
How should parents and pediatricians react to the reports? Medical common sense should prevail, says pediatric radiologist Dr. Michael DiPietro of the C. S. Mott Children's Hospital at the University of Michigan in Ann Arbor. "If alarm prevents people from having tests done that really need to be done, then the chances of harm from that are much greater than the chances of harm from the radiation. The concerns raised by this study should highlight, however, the need for these tests being ordered appropriately, done correctly and interpreted correctly in order to get the maximum information from the minimum of exposure." Dr. Brenner is quick to concur: "The benefits of CAT scans by far outweigh the risks."