gms | German Medical Science

Background and objective: Radioactive material and ionizing radiation are playing a central role in medical diagnostics and therapy. In contrast to radiographic examinations which are associated with a low level of radiation exposure angiographic or computed tomographic (CT) examinations are considerably associated with higher exposure. The benefit of ionizing radiation is opposed by the risk of irreparable damage of the human organism. Situations in which the expected benefits do not outweigh the risks for pediatric patients being particular vulnerable should be determined very carefully.

Our aim was to critically appraise the best available evidence concerning the risk of CT scanning for causing malign neoplasms in exposed children in their life course.

Methods: We searched MEDLINE, The Cochrane Library, DAHTA-Database, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database, NHS Economic Evaluation Database, EMBASE, BIOSIS Previews, SciSearch and EBSCO for publications in English or German in March 2016. We included children up to 16 years examined by CT and with a diagnosis of malign neoplasm. Retrievals were screened by two independent reviewers. The assessment of methodological quality was done by two independent reviewers concerning representativeness, risk of bias, and further limitations. Reporting quality was assessed using the RECORD checklist.

Results: The systematic searches identified four cohort studies. An increased risk of brain tumors in children after exposition to head CTs and by an increase of the number of examinations was shown. For children with predisposing factors an increased risk of tumors of the central nerve system, leukemia, and lymphoma was found. Furthermore, a general risk of malign neoplasms, and a specific risk of lymphoma after CT examinations of different parts of the body could be observed.

Conclusions: Taking into consideration an unclear or high risk of bias as well as lack of comparability due to different research questions, the validity of results is limited.

To adequately examine the risk of CT-induced radiation exposure of children, studies with a follow-up of at least 10 years would have been necessary including documentation of each CT examination and its individual dosage, the body part examined, and applicated contrast media. A verification of indication should have been also reported stratified for the medical discipline of the indicating physician.