Radiation risks assessment of children cancer incidence based on computed tomography examination protocols

The article presents approach to estimating lifetime attributable risk (LAR) of cancer following single computed tomography (CT) scanning in childhood and adolescence. LAR estimating was two-stage process. First methods for calculating equivalent doses to organs and tissues were developed. For estimating LAR of solid cancer from computed tomography organ doses were calculated with the use of dose-length product (DLP) as a measure of absorbed dose. Coefficients for conversion of DLP for CT scans of thoracic, abdominal and pelvis organs to equivalent doses were evaluated. Risks of radiation-induced cancer from computed tomography in relation to age and sex were estimated for CT scans of thoracic and abdominal studies. Lifetime attributable risk of cancer was estimated with ICRP models (Publication 103) and medico-demographic parameters of the Russian population. LAR estimated using organ doses, evaluated with the use of DLP, were compared with the risk estimated with organ doses measured using silicone photodiode dosimeters.