Can CT Scans Raise Cancer Risk?
Jump in CT Scans May Lead to More Cancer, Experts Predict
WebMD News Archive
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
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
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
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.