CT examination of children and the risk of cancer (EPI-CT)

The purpose of the study is to establish a European cohort of children under 20 years of age who have undergone one or more CT examinations to estimate the risk of leukemia, other cancer diseases, and other negative health effects.

Background & aims

It is likely that children and young individuals are more likely to experience negative impact on health after exposure to radiation as compared to adults. The reason for this is a higher sensitivity for effects of radiation and younger individuals have a longer life ahead of them during which the effects of radiation can manifest themselves.

Exams based on computerized tomography (CT) contribute to around 80% of the population’s radiation experienced from medical and diagnostic treatment. There is a large body of knowledge on how high doses of radiation may impact health for adults. Even if the total amount of radiations experienced is low, it is important to ensure that those that undergo medical exams are exposed to as little as possible radiation in these procedures.

Furthermore, it is important to investigate whether risks for health are associated with the use of low-dosage CT exams for children and young individuals. The Cancer Registry of Norway will therefore collaborate with The Norwegian Radiation and Nuclear Safety Authority (DSA) and Oslo University Hospital to analyze data from Norwegian hospitals regarding medical exams of 20 000 Norwegian children and individuals below the age of 20, collected during the timeframe 1985-2015. This cohort is part of a European study including 1.1 million individuals in the same age categories. The study will monitor whether the exposed groups has more diagnosis of leukemia, other cancers or other negative effects on health as compared to the general population for these age groups.

The analyses are performed through the coupling of the Norwegian Cause of Death Registry, the Cancer Registry of Norway and the Medical Birth Registry of Norway. Through these couplings one can monitor registered data on health. Over time, with the overall increase of risk for disease this study may be able to identify adverse effects of radiation during childhood and/or below the age of 20.

The results will contribute to optimize radiation dosages in CT and contribute to developing European and national recommendations for the use of CT for children.


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