“CT utilization in the United States in 2023 was estimated to result in 102 700 (90% UL, 96 400-109 500) projected lifetime cancers, including 93 000 (90% UL, 86 900-99 600) in adults and 9700 (90% UL, 8100-11 600) in children. The leading cancers in adults were lung cancer (21 400 [90% UL, 19 200-24 000]), colon cancer (8400 [90% UL, 7500-9400]), and leukemia (7400 [90% UL, 6100-8900]), whereas the most frequent projected cancers in children were thyroid (3500 [90% UL, 2300-5500]), lung (990 [90% UL, 870-1100]), and breast (630 [90% UL, 550-730]) cancer. Lung and thyroid cancer incidence were higher in female patients, whereas incidence of most other cancers was similar by sex or slightly higher in male patients.
Projected cancer risks per CT examination were estimated to be highest among children who underwent CT at younger than 1 year and decreased with age at exposure. For example, cancer risk in girls younger than 1 year were 20 cancers per 1000 examinations (1900 of 97 000) versus 2 per 1000 in girls aged 15 to 17 years (1100 of 483 600). However, despite the higher risk per examination in children, higher utilization contributed to more projected cancers in adults. CT use in adults aged 50 to 59 years was associated with the highest number of projected cancers: 10 400 (90% UL, 8200-13 000) in female patients and 9300 (90% UL, 7500-11 700) in male patients.
[..] if the number of new cancer diagnoses in the United States remains stable (1.95 million in 2023) and both the utilization and radiation doses from CT remain unchanged in future decades, CT could be responsible for approximately 5% of cancers diagnosed each year. This would place CT on par with other significant risk factors, such as alcohol consumption (5.4%) and excess body weight (7.6%).”
Full article, R Smith-Bindman, PW Chu, HA Firdaus et al., JAMA Internal Medicine, 2025.4.14