A new UCSF-led study projects nearly 103,000 future U.S. cancer cases may stem from CT scans performed in 2023.
Based on data from over 140 healthcare facilities, researchers warn that while individual risks are low, the population-wide impact is growing—and largely preventable.
Understanding the Link: CT Scans and Radiation Exposure
Computed tomography (CT) scans are widely used to diagnose conditions ranging from head injuries to internal organ issues. They provide fast, detailed images using x-rays—making them indispensable in emergency care and treatment planning.
However, this diagnostic advantage comes with a catch: radiation exposure.
According to findings published in JAMA Internal Medicine (April 14, 2025), CT scans administered in 2023 could lead to over 100,000 future cancer cases, equivalent to 5% of all new U.S. cancer diagnoses annually if current trends continue.
What the UCSF Study Revealed
Led by Dr. Rebecca Smith-Bindman, the UCSF research team analyzed over 140 facilities’ CT data via the UCSF International CT Dose Registry.
Using the National Cancer Institute’s Radiation Risk Assessment Tool (RadRAT), they estimated how exposure from these scans might contribute to lifetime cancer risk across different demographics.
A Breakdown of CT-Linked Cancer Estimates
The study highlighted critical trends in how CT scans contribute to projected cancer cases.
CT Use and Estimated Cancer Impact (U.S., 2023)
| Imaging Detail | Estimated Impact |
|---|---|
| Total CT scans performed | 93 million |
| Adults scanned (18+) | 96% |
| Children scanned (under 18) | 4% |
| Estimated future cancer cases | ~103,000 |
| Share of total future diagnoses | ~5% of annual U.S. cancer cases |
| Top contributing scan types | Abdominal & pelvic (40%) |
| Top projected cancers | Lung, colon |
Notable Study Highlights
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Children face higher individual risks, especially those under 1 year of age.
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Adults account for most CT-related cancers, due to higher scan volume.
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Radiation dose per scan varies widely, even for similar procedures.
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Many scans are unnecessary, offering little benefit compared to risk.
Are All CT Scans Risky?
Not exactly. The study’s authors, including Dr. Amy Berrington de González of the Institute for Cancer Research, emphasize that CT scans are still essential—especially when clinically justified.
“For the individual patient, this increased risk is small,” said Berrington de González. “But across millions of scans, these small risks accumulate.”
When used appropriately, the benefit of early diagnosis and treatment far outweighs the radiation risk. But researchers argue that CTs are often used in borderline cases where safer alternatives—like ultrasound or MRI—may suffice.
Practical Ways to Reduce Risk
While CT scans can’t be eliminated from modern medicine, researchers suggest targeted steps to reduce population-level risk:
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Use CT scans only when medically necessary
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Choose non-radiation alternatives when possible
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Standardize and minimize radiation doses per scan
“Reducing the number of scans and reducing doses per scan would save lives,” said Dr. Smith-Bindman.
What This Means for You
If you’re scheduled for a CT scan, ask your healthcare provider if it’s necessary and if safer options are available. If the scan is essential, ensure it uses the lowest possible dose needed for accurate diagnosis.
Stay Informed, Stay Protected
CT scans are powerful tools in modern healthcare—but they come with long-term trade-offs. Understanding when they’re truly needed can help reduce unnecessary exposure.
To explore more about medical imaging safety and cancer prevention strategies, consult trusted sources like the NIH National Cancer Institute or speak with your healthcare provider.
Sources: National Institutes of Health.
Prepared by Ivan Alexander Golden, Founder of THX News™, an independent news organization delivering timely insights from global official sources. Combines AI-analyzed research with human-edited accuracy and context.
