The Reading Room Podcast: Current Insights on Recent Research About Radiation-Induced Cancers with CT Scans, Part 1

In a recently published study, researchers estimated that out of an estimated 93 million computed tomography (CT) exams performed in 2023, there may be 103,000 future cases of radiation-induced cancers. Based on current CT use and radiation dosing levels, the study authors suggested that radiation-induced cancers from CT exposure may account for 5 percent of all cancer cases.

However, in the first part of a new podcast, Joseph Cavallo, M.D., emphasized appropriate perspective with the aforementioned risk modeling study and taking all the risks into account to optimize patient care.

“I would have liked to see a little more discussion about underlying risk in general. They speak to the risk of CT, but we're really not comparing the risk of a CT versus the risk of doing nothing … Hopefully, in all the cases where we're doing CT or other radiation-based imaging, we should be comparing the risk of CT versus the risk of the underlying disease and the risk of complications from the underlying disease, and ultimately, the risk of missing the diagnosis of some of those diseases,” posited Dr. Cavallo, an assistant professor of radiology and biomedical imaging at Yale School of Medicine in Boston.

While the authors of the aforementioned study suggested that multiphase scanning, occurring in 28.5 percent of CT exams, is commonly overutilized, Mahadevappa Mahesh, MS, Ph.D., emphasized that patient history and disease presentation are key considerations.

“Which patients (had the multiphase scanning)? Was it necessary? Because it's very subjective to say overused. … Did any of them have cancer-related studies? Do they have other underlying diseases? (In these cases), you only (get) answers with a triphasic study. That's important to say. I'm not refuting the numbers, but the justification of these numbers is very important,” added Dr. Mahesh, the president of the American Association of Physicists in Medicine (AAPM), and a professor of radiology and radiological sciences at the Johns Hopkins School of Medicine.

(Editor’s note: For related content, see “What New Research Reveals About Computed Tomography and Radiation-Induced Cancer Risk,” “Nine Takeaways from New Research on CT Scans and Radiation-Induced Cancers” and “AI Denoising Bolsters Ultra-Low-Dose CT Detection of Pneumonia Findings in Immunocompromised Adults.”)

For more insights from Dr. Cavallo and Dr. Mahesh, listen below or subscribe on your favorite podcast platform.