Paediatric CT exposure and cancer

Computed tomography (CT) is an imaging method for the three-dimensional representation of the body interior of patients with the help of X-rays. Whether CT examinations in childhood can cause cancer later in life has been studied in large-scale studies in the recent years. After the publication of results of these studies the Federal Ministry for the Environment commissioned the German Commission on Radiological Protection (SSK) to evaluate the new scientific data.

• Is there a causal relationship between a CT scan in childhood and a subsequent development of cancer, depending on the level of radiation exposure?
• How common are CT scans on children in Germany and is there a trend?
• Are there groups of people who are particularly at risk of developing cancer after a CT scan?
• Is there a need for action based on the findings?

• Current epidemiological studies show that there is a connection between the level of radiation dose from CT scans in childhood and the risk of certain cancers (malignant brain tumours, haematological malignancies such as leukaemias) in later life. 
• In Germany, around 70,000 CT scans on children were performed per year between 2005 and 2021. This corresponds to 5.26 to 5.64 examinations per 1,000 children per year. 
• The use of CT in children and adolescents requires a strict indication setting. Children with certain, very rare genetic diseases are a particularly vulnerable at-risk group, where the increased cancer risk must be considered. Whenever possible and medically useful, procedures without ionising radiation (e.g. ultrasound, magnetic resonance imaging) should be preferred in all children. 
• Planned CT examinations should be carried out in specialised institutions for paediatric and adolescents' radiology. These institutions can assess the risks, the greater sensitivity of children to ionising radiation and the often individualised questions due to their specialisation. They use individually adjusted CT settings that take into account the age, weight, and body size of each child being examined to reduce the necessary radiation exposure. 
• There is a need for action in planning and providing alternative examination procedures for children and adolescents without X-rays (e.g. magnetic resonance imaging, MRI). This also requires adjusting the cost calculation and developing settings that are especially suitable for children.