The role of biomarkers in measuring radiation exposure

The rationale behind the use of a biomarker as an endpoint of radiation effect is that it is closer to the final biological endpoint of importance, usually cancer, and that it is affected by individual susceptibility as well as the exposure. Current biomarkers will be reviewed. They all have problems of sensitivity, specificity, and precision, and the quantitative relationship between the measurement of a biomarker and the likelihood of development of cancer is unknown. These problems are substantial when groups are studied, but they are even more so when individuals are studied. At least until new and better biomarkers can be identified, biomarkers may be better suited to prospective identification of individuals susceptible to radiation rather than retrospective quantification of radiation effects