Can CT Scans Raise Cancer Risk?
Jump in CT Scans May Lead to More Cancer, Experts Predict
Bomb Survivors and CT Risk continued...
American College of Radiology (ACR) Board of Chancellors chairman Arl Van Moore Jr., MD, acknowledges that the increase in CT usage may lead to more cancers. But he adds that it is impossible to quantify the risk based on the studies of Hiroshima and Nagasaki bomb survivors.
"You can't equate the radiation you get from CT to that from an atomic bomb," he says. "Saying that 2% of all cancers will be caused by CT scans is nothing but a guess at this point."
But Moore tells WebMD that the ACR is concerned about unnecessary radiation exposure from medical imaging.
In a position statement published earlier this year, an ACR task force acknowledged that the rapid growth of CT and other types of scanning may "result in an increased incidence of radiation-related cancer in the not-too-distant future."
CT Scans for Screening
CT scanning is increasingly being talked about as a potential screening tool for lung and colorectal cancers and other diseases.
Whole-body CT scanning is also being marketed to healthy people without symptoms or suspicion of disease as a proactive health care strategy, although this use is controversial.
The ACR does not endorse whole-body CT scanning for patients without symptoms, and the FDA notes that whole-body screening provides "uncertain benefit with the potential for some risk."
"We are at a sentinel event where medical exposure is now the biggest source of radiation exposure to the U.S. population," New Mexico radiologist Fred Mettler, MD, said at the news conference. "And we can expect this exposure to get much bigger when these screening applications kick in."
While the case for the use of CT to diagnose existing symptoms is much clearer, Brenner and Hall argue that CT scanning is still too widely used, especially in hospital ERs.
"If you go to an emergency room with a belly ache or a chronic headache you will almost certainly be given a CT scan even before you see a doctor," Brenner says.
It is also common for patients to have duplicate CT scans performed for the same medical condition as they change doctors or hospitals, he adds. One solution to this would be to provide patients with a DVD of their CT scan to take with them from doctor to doctor.