"The estimates, while based on the best models available to the authors, are indirect, so there is considerable uncertainty about the estimates," Stephen Duffy, emeritus professor of Cancer Screening at Queen Mary University of London, said in a statement.
"Thus, I would say to patients that if you are recommended to have a CT scan, it would be wise to do so."Duffy also highlighted that in the context of a person's overall risk of cancer, CT scans don't move the needle much.
There were a little over 100,000 cancers linked to 93 million scans.
"This amounts to around a 0.1 percent increase in cancer risk over the patient's lifetime per CT examination," he said.
The lifetime risk of cancer in the US population is around 40 percent.
Thus, the additional risk from CT scans "is small." Overall, when a CT scan is deemed necessary, the "likely benefit in diagnosis and subsequent treatment of disease outweighs the very small increase in cancer risk."Doreen Lau, a cancer biology expert at Brunel University of London, agreed: "The findings dont mean that people should avoid CT scans when recommended by a doctor.
In most cases, the benefit of detecting or ruling out serious illness far outweighs the very small risk of harm."Still, the rise in CT scans in recent years may suggest that doctors could cut back on their use.
In an accompanying editorial, Ilana Richman of Yale University and Mitchell Katz of NYC Health and Hospitals discussed ways that doctors could make sure they're balancing risks and benefits before using CT scans, including using diagnostic algorithms and offering alternative imaging options, such as ultrasounds and magnetic resonance imaging (MRIs)."As with all complex problems, there will be no simple solution," they write.
But, "educating clinicians about avoiding low-value testing and, in circumstances where alternatives are readily available, involving patients in the decision to do a CT scan may help shift culture and practice."