A new study highlights the potential cancer risk associated with millions of CT scans performed annually in the US. The scans, which diagnose conditions ranging from tumors to kidney stones, emit ionizing radiation that may increase cancer risk.
According to Dr. Rebecca Smith-Bindman, a leading author of the study and an epidemiology professor at the University of California, San Francisco, “Medical imaging has potential benefits” but also comes with risks. The researchers estimate that 103,000 cancer diagnoses could result from 93 million scans performed in the US in 2023 alone.
The study suggests that some CT scans are unnecessary, leading to excessive radiation exposure. The dose of radiation emitted by a scan can vary widely, even within the same facility, and can be up to 50 times stronger at one location than another.
Dr. Dana Smetherman, chief executive officer of the American College of Radiologists, praised the study for raising awareness about the risk of radiation from CT scans. She emphasizes that patients should ask their healthcare providers questions about the test, its benefits, and potential risks.
To reduce exposure to radiation, experts recommend optimizing the dose used in each scan and limiting unnecessary scans. The University of California, San Francisco, has launched a website called Know Your Dose to empower patients to ask questions about radiation exposure from scans.
While there are no federal standards for dosages, hospitals and imaging facilities share information about their scanners’ radiation emissions through Medicare’s measurement tool. Smith-Bindman and her colleagues are developing a quality measure for CT scanning, with one-third of scans exceeding the targets in testing.
Source: https://www.npr.org/sections/shots-health-news/2025/04/16/g-s1-60488/ct-scan-cancer-risk-ionizing-radiation