A new study has projected that radiation exposure from computed tomography (CT) scans in the United States will result in approximately 103,000 future cancers. This analysis, based on 93 million CT exams performed on 62 million patients in 2023, highlights the long-term cancer risks associated with CT imaging, a known carcinogen.
The study, using a risk model that considered patient age, sex, and CT category, estimated that 93% of these radiation-induced cancers would occur in adults, despite higher per-exam cancer risks for children. The most common cancers linked to CT radiation included lung cancer, colon cancer, leukaemia, and bladder cancer, with lung cancer making up the largest portion at around 22,400 cases. Notably, abdominal and pelvic CT exams were the largest contributors, accounting for 37% of the total cancer burden.
With annual CT use increasing, the study suggests that, if current practices continue, CT-associated cancers could eventually represent 5% of all new cancer diagnoses in the U.S. The researchers stress the need for careful consideration of CT use and radiation doses to minimise potential harm, particularly in children and younger adults who are more vulnerable to radiation-induced cancers over their lifetime.
This alarming projection calls attention to the importance of balancing the diagnostic benefits of CT scans with the long-term risks, urging healthcare providers to assess the necessity of each scan carefully.
Reference
Smith-Bindman R et al. Projected lifetime cancer risks from current computed tomography imaging. JAMA Intern Med. 2025; doi:10.1001/jamainternmed.2025.0505.
