Key points from article :
A major new study led by Dr. Rebecca Smith-Bindman of the University of California-San Francisco raises serious concerns about the widespread use of CT scans and their potential link to cancer. Published in JAMA Internal Medicine, the research, funded by the National Institutes of Health, estimates that CT scans may contribute to 5% of all cancers annually in the U.S.
The team analysed data from over 93 million CT exams performed in 2023 and found that radiation exposure from these scans could cause significantly more cancers than previously thought—up to three to four times more than earlier estimates. Alarmingly, infants under one year old were found to be ten times more likely to develop cancer from CT-related radiation than other age groups.
The most common cancers linked to CT scans included lung, breast, colon, leukemia, and bladder cancers, especially following scans of the abdomen, pelvis, and head. While CTs are vital tools for diagnosis, the researchers emphasized that many are performed unnecessarily, such as those for headaches without other symptoms or routine upper respiratory issues.
Smith-Bindman cautioned that although the cancer risk from a single CT scan is low, the sheer number of scans being performed—many without clear medical benefit—amplifies the risk at the population level. The study calls for more judicious use of CT imaging and lower radiation doses to reduce preventable cancer cases. As Dr. Patricia Nguyen of Stanford (who was not involved in the study) noted, patients should feel empowered to ask, "Why am I getting this scan, and will it change my care?"
