CT scan is commonly used diagnostic modality for various disorders. It delivers higher radiation doses than most imaging modalities.
It is now a well known fact that children are more sensitive to radiation than adults and they have higher relative risk of cancers including leukemia, brain, breast, skin and thyroid cancers following exposures.
Why Children are at a greater risk than adults for developing cancer after being exposed to ionizing radiation?
It may be attributable to
a) Their developing bodies
b) Long life expectancy
Scientists from Netherland conducted a study to evaluate leukemia and brain tumor risk following exposure to low ionizing radiation from CT scans in childhood. Leukemia was the first radiation-induced cancer reported in Atomic bomb survivors in Hiroshima and Nagasaki, Japan. It was prevalent predominantly in children. The first evidence of pediatric leukemia was reported 3 years after exposure and reached its peak during the 6–8 year period.
1,68,394 children younger than 18 years of age and who had received one or more CT scan in a Dutch hospital between 1979 and 2012 were included in the study. They found that CT related radiation exposure increases brain tumour risk. There was no association with leukemia development. Estimatedly 10000 CT scans are done among children in Netherlands annually. At least 1 in 120 pediatric brain tumours diagnosed in year is attributed to radiation exposure. Study suggested careful justification of pediatric CT scans and dose optimization are essential to minimize risk of tumor development in future.
Image source: clevelandclinic.org