Medical Imaging and Risk for Blood Cancers in Children and Adolescents

Radiation exposure from imaging studies, primarily computed tomography (CT), is a recognized risk factor for hematologic malignancy. To examine the relation between cumulative radiation exposure and risk for subsequent hematologic cancer, researchers retrospectively examined data on 3.7 million children and adolescents (a total of 35 million person-years) through age 21.

The researchers calculated radiation exposures from radiographs, fluoroscopy, angiography, nuclear medicine, and CT. Only cancer diagnoses that lagged exposure by at least 6 months were included, to avoid concerns that undiagnosed cancers had prompted the imaging. For reference, bone marrow doses of radiation for common studies vary by age of child, but the averages a…