Carcinogenic risk in diagnostic nuclear medicine: biological and epidemiological considerations.

During the last decade new data have become available on the mechanism of carcinogenesis and on cancer induction by ionizing radiation. This review concentrates on these two items in relation to the use of radiopharmaceuticals in diagnostic nuclear medicine. On the basis of reports of expert committees, the concept of radiation risk is elucidated for high and low doses. Mortality risk factors due to ionizing radiation are put in perspective to other risks. The extra risk for patients who undergo a scintigraphic examination for fatal cancer is very small and is of the order of 1.4 x 10(-4). It is most unlikely that this figure can even be verified by actual measurement since the majority of nuclear medicine patients will die of other causes before the radiogenic cancer manifests itself.