Breath Test for Biomarkers in Humans Receiving Total Body Irradiation

The effect of radiation on normal tissue varies widely between individuals. Consequently, a test to measure tissue response to radiation could be clinically useful by permitting more accurate titration of dosage in patients undergoing radiotherapy. Also, in view of emerging concerns about possible nuclear terrorism a test for exposure to radiation might also be useful in evaluating victims of a "dirty bomb" explosion. A number of different techniques have been previously reported in epidemiological studies for the estimation of prior radiation exposure. This study explores one approach to estimating radiation exposure by measurement of increased oxidative stress which can be detected by a breath test. In this study subjects undergoing significant exposure to therapeutic radiation will provide breath samples for analysis in a central laboratory. The hypothesis of the study is that the analysis of these samples will lead to the identification of a set of markers of radiation exposure.