It is indeed possible to develop cancer from exposure to CT scans over time, primarily due to the ionizing radiation these scans emit. CT (computed tomography) scans use X-rays to create detailed images of the inside of the body, and this process involves exposure to ionizing radiation, which can damage cells and DNA. This damage has the potential to lead to cancer, especially with repeated or high-dose exposures.
The risk of cancer from CT scans is generally considered low for any single scan, but it increases with the number of scans a person undergoes and the cumulative radiation dose received. Children and young adults are more sensitive to radiation and thus have a higher risk compared to older adults. Studies have found associations between CT scan radiation and increased risks of certain cancers, including blood cancers, brain tumors, lung, colon, bladder, and breast cancers. For example, large epidemiological studies pooling data from multiple countries have shown increased risks of blood and brain tumors in children and young adults following CT imaging.
The overall contribution of CT scan radiation to cancer incidence is estimated to be significant on a population level due to the large number of scans performed annually. One study projected that radiation from CT scans could account for about 5% of all new cancer cases in the United States, translating to roughly 100,000 new cancers per year. This risk is comparable to other known cancer risk factors such as alcohol consumption and excess body weight.
Despite these risks, CT scans remain a crucial diagnostic tool. The benefits of a medically necessary CT scan—such as accurate diagnosis, guiding treatment, and detecting serious conditions—usually outweigh the small individual risk of radiation-induced cancer. However, concerns arise when CT scans are overused or performed without clear clinical indication, potentially exposing patients to unnecessary radiation.
Efforts to reduce cancer risk from CT scans include advances in imaging technology that lower radiation doses, optimization of scanning protocols, and regulations requiring hospitals to track and report radiation doses. Maintaining strict guidelines and dose monitoring helps minimize unnecessary radiation exposure and prevent avoidable cancers.
In summary, while CT scans do carry a risk of causing cancer over time due to ionizing radiation exposure, this risk is generally low for individual patients when scans are medically justified. The risk increases with repeated scans and higher doses, particularly in younger patients. Balancing the diagnostic benefits of CT scans against their radiation risks is essential, and ongoing improvements in technology and regulation aim to keep these risks as low as possible.
