Latest news with #RebeccaSmith-Bindman
Arab Times
15-04-2025
- Health
- Arab Times
Experts warn of cancer risks from overuse of CT scans
NEW YORK, April 15: US researchers are raising concerns over the potential health risks linked to the increasing use of CT (computed tomography) scans — a common diagnostic tool that uses X-rays to create detailed images of the body. While these scans play a vital role in detecting diseases, experts say the radiation exposure they involve could elevate cancer risks, particularly with frequent or unnecessary use. CT scans differ from MRI (magnetic resonance imaging) scans, which use magnets and radio waves instead of radiation. Though both machines resemble tube-like structures and produce high-resolution images, the radiation used in CT scans belongs to the high-energy end of the electromagnetic spectrum — the same range that includes ultraviolet (UV) rays and gamma rays. This type of "ionizing" radiation has enough energy to damage tissue at the molecular level, potentially leading to cancer. "CT can save lives, but its potential harms are often overlooked," said Dr. Rebecca Smith-Bindman, a radiologist at the University of California San Francisco and lead author of the study. The research modeled cancer risk in 61.5 million U.S. patients who had undergone CT scans, estimating that around 103,000 cancer cases could eventually result from the radiation exposure over their lifetimes. This would represent about 5% of the annual cancer diagnoses in the U.S., assuming current scanning rates continue. CT scan usage has risen by approximately 30% since 2007, with older adults — especially those aged 60 to 69 — being the most frequent recipients. The study found abdominal and pelvic CT scans posed the highest risk for adults, while head scans were most concerning for children. Infants scanned before their first birthday faced a tenfold higher risk of developing cancer compared to older children. 'Our estimates put CT on par with other significant risk factors, such as alcohol consumption and excess body weight,' Dr. Smith-Bindman noted. 'Reducing the number of scans and minimizing radiation doses could save lives.' She emphasized that many scans are performed unnecessarily, including those ordered for mild symptoms like headaches or respiratory infections. Additionally, patients often receive higher doses of radiation than required, further increasing their health risks. Other experts echo these concerns. Dr. Pradip Deb, a radiation safety specialist at RMIT University in Australia, who was not involved in the study, agreed that high-energy radiation is a known carcinogen. However, he cautioned that not every individual exposed to radiation will develop cancer, and personal risk varies. 'Radiation is a well-established cause of cancer, but we must balance that knowledge with the benefits CT scans provide,' said Dr. Deb. 'They are essential in diagnosing conditions that can significantly improve a patient's quality of life.' He added that while the risks should not be ignored, patients should not panic. Instead, medical providers must focus on using CT scans only when truly necessary and opt for lower-dose or non-radiation alternatives where available. Ultimately, researchers call for more responsible and regulated use of CT scans in healthcare to minimize avoidable harm while continuing to harness their life-saving benefits.
Yahoo
14-04-2025
- Health
- Yahoo
CT scans may increase your risk of cancer, US study suggests
Computed tomography scans – also known as CT, or Cat, scans – may be causing 1 in 20 cancers, a study has found. About five million of the scans, which use X-rays to create detailed internal pictures of the body, are carried out each year on the NHS. But new research from the University of California (UC) suggests they could lead to lung, breast and other cancers, with a tenfold increased risk for babies. Modelling showed that nearly 103,000 cancers were expected from the 93 million CT scans that were performed in 2023 in the US – about three to four times more than previous assessments. If the same rates were extrapolated to Britain, it suggests that hundreds of cancers are being triggered by the scans. 'CT can save lives, but its potential harms are often overlooked,' said Dr Rebecca Smith-Bindman, UC San Francisco radiologist and professor of epidemiology. 'Our estimates put CT on par with other significant risk factors, such as alcohol consumption and excess body weight. Reducing the number of scans and reducing doses per scan would save lives.' CT scans are used to diagnose a range of conditions including broken bones, tumours, internal bleeding and cardiovascular problems. But ionising radiation can damage DNA and trigger disease. For the new study, researchers analysed 93 million exams from 61.5 million patients in the US to calculate how often cancer developed. They found that in adults, scans of the abdomen and pelvis were likely to cause most problems, while in children the biggest risk came from CTs of the head. Cancers predicted to arise from the excess radiation included lung, colon, leukaemia, bladder and breast, and thyroid. The risks were highest among those who underwent CT when they were under one year old. Researchers warned that medics should think twice before giving scans for more trivial conditions such as upper respiratory infections or headaches, and make people aware of the dangers when discussing treatment. However, British experts said that the benefits from CT scans were likely to outweigh the risks. Lynda Johnson, professional officer for clinical imaging and radiation protection at the Society of Radiographers, said: 'Accurate communication around the benefits and risks of CT is essential to protect the public from harm. 'Focusing on risk alone is not helpful and, in some cases, might prevent a person from attending a scan that could provide early diagnosis of cancer. 'Anyone undergoing a CT scan must be provided with balanced, accurate and relevant information to enable them to understand what it means to them as an individual in terms of their diagnosis, treatment and potential long-term care.' Experts also pointed out that CT scan rates are much higher in the US than in the UK, where imaging is used more conservatively and with stricter clinical justification. Dr Doreen Lau, a lecturer in inflammation, ageing and cancer biology at Brunel University of London, said: 'The findings don't mean that people should avoid CT scans when recommended by a doctor. 'In most cases, the benefit of detecting or ruling out serious illness far outweighs the very small risk of harm. What this research highlights is the need to minimise unnecessary imaging and use the lowest dose possible, particularly in settings where CT usage is high. 'Where appropriate, clinicians may also consider alternative imaging methods that do not involve ionising radiation, such as MRI or ultrasound – especially for younger patients, or when repeat imaging is anticipated.' Stephen Duffy, emeritus professor of cancer screening at Queen Mary University of London, added: 'I would say to patients that if you are recommended to have a CT scan, it would be wise to do so.' The research was published in the journal Jama Internal Medicine. Broaden your horizons with award-winning British journalism. Try The Telegraph free for 1 month with unlimited access to our award-winning website, exclusive app, money-saving offers and more.
Yahoo
14-04-2025
- Health
- Yahoo
CT Scans Projected to Result in 100,000 New Cancers in The US
More Americans are receiving computed tomography (CT) scans than ever before, and while this technology can save lives, some scientists are concerned about the potential for low doses of ionizing radiation to increase cancer risks. At an individual level, the theoretical chance of developing cancer from a CT scan is thought to be very minimal, if it exists at all, and patients should not be scared of undergoing these tests if they are deemed medically necessary. However, the number of CT examinations performed each year in the US has increased by more than 30 percent since 2007, and researchers suggest that unwarranted tests are exposing the population to unnecessary radiation. A team in the US and the UK now predicts that low levels of ionizing radiation from CT scans could theoretically account for 5 percent of all new cancer diagnoses in the US. CT scans conducted in 2023 could be responsible for an estimated 103,000 future cases of cancer. That's based on some assumptions and historical data from high radiation events, but if right, it would put CT scans on par with other significant risk factors for cancer, like alcohol consumption, at least at a population level. "CT is frequently lifesaving, yet its potential harms are often overlooked, and even very small cancer risks will lead to a significant number of future cancers given the tremendous volume of CT use in the United States," write the international team of analysts, led by epidemiologist Rebecca Smith-Bindman from the University of California, San Francisco. As of now, these are just theoretical risks, but that doesn't mean they aren't worth considering. While scientists know that high doses of radiation cause cancer, conclusive evidence to link low-level radiation to cancer is lacking. The potential association is mostly based on long-term studies of atomic bomb survivors and those exposed to nuclear power plant meltdowns. For instance, in a group of 25,000 Hiroshima survivors, who received a dose of ionizing radiation on par with three or more CT scans, there was a slight but significant increase in cancer risk across a lifetime. Whether those results extend to CT scans remains hotly debated, and the theoretical risks must be weighed against the myriad benefits of this technology, which can now alert patients and doctors to a whole variety of hidden diseases and injuries with very low doses of radiation (about the same amount you absorb from your environment over three years). The new predictions on cancer risk are again based on these historical tragedies, but compared to previous analyses, they consider more detail on the actual radiation exposure, which can depend on the type of CT device, the scanning duration, the size of the patient, and the sensitivity of their targeted body part. The anonymous data comes from 143 hospitals and outpatient facilities across the US, catalogued in the UCSF International CT Dose Registry. Using statistics from 2016 to 2022, researchers predicted 93 million CT examinations were carried out in 2023, on roughly 62 million patients. Based on the associated radiation risks, the team estimates that CT scans in 2023 may be tied to 103,000 future cancers. "To empirically quantify lifetime risk would require decades-long follow-up studies of very large populations," the authors admit. However, their results suggest that some people may be more susceptible to cancer from low-dose ionizing radiation than others. Adults receive the vast majority of CT scans, but estimated radiation-induced cancer risks were higher in children and adolescents. Those receiving CT scans at under one year of age, for instance, seem to have a higher potential lifetime risk for thyroid cancers, and this appears more common among female patients. Far more research is needed to confirm if low-dose ionizing radiation actually impacts a person's cancer risk, and how. "Estimated overall cancer risks from CT radiation doses are similarly high in Australian studies, says medical radiation specialist Pradip Deb from RMIT University. She argues it is important to avoid unnecessary CT scans if radiation-free procedures can do the same job. Radiographer Naomi Gibson, President of the Australian Society of Medical Imaging and Radiation Therapy, agrees. "Although the findings highlight the need for vigilance around long-term radiation exposure, this should not discourage the use of CT imaging when clinically justified," Gibson explains. "In appropriately selected cases, the diagnostic and therapeutic value of CT scans significantly outweighs the potential radiation-associated risks." The study was published in JAMA Internal Medicine. Ozempic Reshapes The Kinds of Food People Eat. Here's What Happens. 'Landmark Moment': New Breast Cancer Treatment Approved in UK Researchers Identify New Blood Group After 50 Year Mystery
