A large-scale retrospective study of 3.7 million children found an association between radiation exposure from medical imaging and a small but significantly increased risk of developing hematologic cancers (primarily leukemia).
Finding: Cancer risk increased with cumulative radiation dose
Dose-Response: For the highest exposure group (50 to <100 mGy), the Relative Risk (RR) for hematologic cancer was 3.59 compared to no exposure.
Attributable Risk: An estimated 10.1% of hematologic cancers in the cohort may have been attributable to medical imaging radiation, with CT scans being a major contributor.
Vulnerability: Children are more susceptible to radiation-induced cancer due to their heightened radiosensitivity and longer life expectancy for the cancer to manifest.
Take Away: Providers should critically assess the necessity of high-dose imaging like CT scans and use the lowest effective dose or possible alternative imaging (e.g. US, MRI, etc.) to prevent unnecessary cumulative exposure.
Medical Imaging and Pediatric and Adolescent Hematologic Cancer Risk. N Engl J Med. 2025 Oct 2;393(13):1269-1278. doi: 10.1056/NEJMoa2502098. Epub 2025 Sep 17. PMID: 40961449; PMCID: PMC12445590.