Are CT Scans Causing Higher Cancer Rates?Dec 31, 2007 | Parker Waichman LLP CT Scans could be putting Americans at a slightly higher risk of cancer, a recently-released study says. According to researchers at the Columbia University Center for Radiological Research, the 62 million CT Scans American’s receive every year could be increasing the cancer rate by as much as 2%. More disturbingly, the effects of CT scans on the cancer rates of children could be even more pronounced.
CT Scans, also called CAT Scans, produce three-dimensional x-ray images of the body that can be quickly taken in multiples and be displayed on a screen. Diagnosticians favor CT Scans because they can reveal abnormalities that are too small or obscured to be seen by more traditional x-rays. CT Scans have proven to be particularly useful in diagnosing trauma and cancer patients.
The latest CT Scan research, published in the New England Journal of Medicine, found that the number of CT Scans most people are exposed to has risen dramatically in the past 27 years. In 1980, doctors ordered an average of 3 million scans per year in the United States. Now, about 62 million CT Scans are done each year in this country. The dose of radiation received by patients subject to a CT Scan can be 50 to 100 times larger than that of a traditional x-ray. That is exactly where the problem of CT Scan overuse lies. The type of radiation used in CT Scans, ionizing radiation, has the capacity to damage DNA, causing cells to mutate. This in turn leads to cancer. While the risk of one CT Scan to an individual is small, the study’s authors wrote that they are concerned about the built-up risk of frequent CT Scans over time. In a few decades, as many as 2% of all cancers in the United States might be caused by radiation from CT scans given now. In their article, the Columbia researchers wrote the evidence of cancer risk from CTs is "reasonably convincing" for adults and "very convincing for children."
The authors of the New England Journal of Medicine report said they where not trying to scare people who need CT scans away from having them. However, using the scans to screen people with no symptoms of illness has not been shown to save lives and could be doing far more harm than good. The rise in CT Scans can be attributed, in part, to an increase in “defensive” medicine. This occurs, for example, when people who are admitted to an emergency room are routinely given a CT Scan even before receiving a diagnosis or being seen by doctor. Controversial uses of CT Scans for whole-body scanning, virtual colonoscopy and lung cancer screening have also made CT Scans more prevalent.
The American College of Radiology is developing a radiation dose registry in an effort to track patient exposure and study the long-term effects of radiography. In 2006, the American Medical Association House of Delegates adopted policy supporting such a registry.