New research links routine CT scans to over 100,000 cancer cases annually in the United States, placing this common diagnostic procedure on par with alcohol as a cancer risk factor.
At a Glance
- A study by the Institute of Cancer Research estimates CT scans may cause approximately 103,000 new cancer cases annually in the US
- Nearly 10,000 of these cases occur in children, who face higher risks from radiation exposure
- CT-associated cancers could account for 5% of all new cancer diagnoses if current practices continue
- Approximately 93 million CT examinations were performed in the US in 2023 on 62 million patients
- Medical experts recommend avoiding unnecessary scans and reducing radiation doses, especially for pediatric patients
Hidden Dangers of a Common Diagnostic Tool
A groundbreaking study from the Institute of Cancer Research in London has uncovered alarming evidence linking routine CT scans to a significant number of cancer cases in America. The research, published in JAMA Internal Medicine, projects that approximately 103,000 radiation-induced cancers could result from CT examinations performed in 2023 alone.
This places CT scans alongside alcohol consumption as a major contributor to cancer risk, potentially accounting for about 5% of all cancer diagnoses in the United States if current practices continue unchecked.
The sheer volume of CT scans performed annually in America is staggering. In 2023, medical facilities conducted approximately 93 million CT examinations on 62 million patients across the country. While these scans provide valuable diagnostic information, the cumulative radiation exposure across the population presents a significant public health concern. The highest number of projected cancers stems from abdomen and pelvis CT scans in adults, followed closely by chest CT scans.
Children at Higher Risk
The study findings are particularly concerning for younger patients. Children and adolescents face a substantially higher risk of developing cancer from CT scan radiation exposure compared to adults. Nearly 10,000 of the projected 103,000 annual cancer cases occur in children, despite adults undergoing CT scans at much higher rates. This disproportionate risk emphasizes the need for extreme caution when considering CT scans for pediatric patients.
“While CT scans are immensely beneficial in diagnosing and detecting many conditions, including cancer, they do involve exposure to ionizing radiation that has been shown to increase the risk of developing cancer,” Berrington said in a statement.
The types of cancers most commonly linked to CT scan radiation include lung cancer, colon cancer, leukemia, and bladder cancer. For female patients, breast cancer represents the second most common radiation-induced malignancy. These findings highlight the importance of balancing the immediate diagnostic benefits of CT scans against their long-term cancer risks, especially for patients who may require multiple scans over their lifetime.
Unnecessary Exposure and Dosage Concerns
A troubling aspect of the research involves unnecessary CT scan exposure. A 2015 Consumer Reports investigation discovered that up to one-third of CT scans might be completely unnecessary, exposing patients to radiation without justifiable medical benefit. Additionally, radiation doses from CT scans vary dramatically among clinics, with some patients receiving doses significantly higher than required for accurate diagnosis.
“Many patients still routinely receive radiation doses two or three times what they should,” Dr. Rebecca Smith-Bindman, a Professor at the University of California-San Francisco Medical School, told NBC. “We keep doing more and more CTs, and the doses keep going up. It’s unfathomable,” she added.
Balancing Benefits and Risks
Medical experts emphasize that CT scans remain a crucial diagnostic tool despite these concerning findings. The individual risk from a single CT scan is relatively small, and in many cases, the immediate diagnostic benefits outweigh the long-term cancer risk. However, the cumulative effect across millions of patients creates a significant public health challenge that requires attention from healthcare providers, regulators, and patients alike.
“It’s important to note that for the individual patient, this increased risk is small, and the benefits far outweigh the risks if the scan is clinically justified. But when millions of CT scans are being carried out across the population, these small risks do add up,” she said.
The Centers for Medicare and Medicaid Services have responded to these concerns by implementing stricter assessment requirements for CT scan radiation doses. Healthcare professionals are now advised to carefully evaluate the necessity of each scan, consider alternative imaging options when appropriate, reduce radiation doses to the minimum required for diagnosis, and educate both clinicians and patients about the risks of unnecessary testing. These measures aim to preserve the valuable diagnostic benefits of CT technology while minimizing its cancer risks.
