Nine Takeaways from New Research on CT Scans and Radiation-Induced Cancers
Recently published research projected that 103,000 future cases of radiation-induced cancer would result from 93 million computed tomography (CT) exams performed in the United States in 2023.
In a risk modeling study that incorporated current utilization and radiation dosing for computed tomography (CT) scans, researchers projected that radiation-induced cancers from CT exams may eventually comprise 5 percent of newly diagnosed cancers annually.
Here are nine key takeaways from the research, which was recently published in JAMA Internal Medicine and discussed in a video interview with lead study author Rebecca Smith-Bindman, M.D., the director of the Radiology Outcomes Research Laboratory and a professor of epidemiology and biostatistics at the University of California, San Francisco (UCSF) School of Medicine.
1. The researchers projected that 103,000 future cancers would occur as a result of CT exams performed in 62 million patients in 2023. This would amount to a projected .0017 incidence of future radiation-induced cancers attributable to CT scans.
Newly published risk modeling research projects that computed tomography (CT) scans performed in 2023 may lead to 103,000 future cases of radiation-induced cancer. (Photo courtesy of Adobe Stock.)
2. Based on current utilization and radiation dosing practices for CT scans, the study authors estimated that radiation-induced cancer from CT scans could account for approximately 5 percent of cancer cases annually. In comparison, recent research has demonstrated that excess body weight and alcohol consumption contribute to 7.6 percent and 5.4 percent, respectively, of cancer diagnoses, according to the researchers.
3. Comparing 2007 and 2023 data, the study authors noted over a 25 percent increase in annual CT exams (from 68.7 million to 93 million).
4. The researchers projected that head CT scans would account for 5,100 cases or 53 percent of future radiation-induced cancers in children.
5. Abdominal and pelvic CT scans were projected to cause 37,500 cases or 37 percent of future radiation-induced cancers.
6. Noting the dose modeling in this study accounted for multiphase scanning in contrast to a prior 2007 analysis of CT and projected radiation-induced cancers, the researchers estimated that multiphase scanning occurs in 28.5 percent of CT exams.
7. The study authors projected that lung cancer would account for 22,400, or 21.7 percent, of future cases of radiation-induced cancer from CT scans, with 70 percent of the cases occurring in female patients.
8. Dosing of the pancreas in pediatric CT exams was 29 percent higher for boys between 5 to 9 years of age versus girls of the same age range (21.5 mGy vs. 16.7 mGy), according to the researchers.
9. The highest number of projected cases of future radiation-induced cancers (19,700) were associated with CT use during one’s sixth decade of life.
