New Delhi– Repeated exposure to unnecessary CT scans may pose a cancer risk equivalent to well-known factors like alcohol consumption and obesity, according to a new study led by researchers at the University of California, San Francisco (UCSF).
Published in JAMA Internal Medicine, the study estimates that radiation from CT scans may account for about 5 percent of all cancer cases annually. The findings raise concerns about overuse and excessive radiation doses in medical imaging.
“CT scans can be lifesaving, but their potential harms are often underappreciated,” said Dr. Rebecca Smith-Bindman, a UCSF radiologist and senior author of the study. “Our estimates place the cancer risk from CT radiation on par with significant lifestyle-related risks such as drinking alcohol and being overweight.”
The study analyzed data from 93 million CT exams conducted in the U.S. in 2023, covering 61.5 million patients. Based on their calculations, the researchers predict that nearly 103,000 cancers could result from these scans—three to four times higher than earlier projections.
Infants, children, and adolescents were found to be especially vulnerable, with those under one year of age facing the greatest risk. Common cancers projected in children include thyroid, lung, and breast cancer. Among adults, the risk was highest for lung, colon, breast, bladder cancer, and leukemia.
While CT scans are a critical diagnostic tool, they expose patients to ionizing radiation—a known carcinogen. The risk increases with the number of scans and the radiation dose per scan.
The data also showed that CT scan usage increases with age, peaking among adults aged 60 to 69. Children represented about 4.2 percent of the total scans performed.
“Reducing unnecessary scans and lowering the radiation dose where possible could prevent thousands of cancers,” Smith-Bindman added.
The study highlights a growing need for more judicious use of CT technology, particularly when safer alternatives are available. (Source: IANS)
