Modelling the frequencies of chromosomal aberrations in peripheral lymphocytes of patients undergoing radiotherapy

Biological dosimetry based on the analysis of cytogenetic damage in peripheral lymphocytes of the exposed person is a well established technique [10]. The absorbed dose is estimated by comparing the scored number of aberrations with a calibration curve, obtained by in vitro irradiation of whole blood collected from control persons. Several authors have validated this procedure by testing experimentally that, after a uniform whole body exposure of animals, the frequency of aberrations induced by a given dose was essentially the same as that induced in vitro [2, 3, 18]. Also, [14] found good agreement between results of in vitro irradiation of blood and partial-body irradiation of rabbits, when the in vivo exposure time was long enough for the whole peripheral blood to flow through the irradiated field. The calibration curves and the dose-response curves following in vivo irradiation with gamma rays are best fitted by a linear-quadratic equation [10]. Following partial-body exposure of a short duration, the dose estimation becomes less precise because the cell population in a collected blood sample will be composed of irradiated and non-irradiated cells. Clearly, the uncertainty is inversely related to the volume of the exposed part of the body and the exposure time [14]. A situation where this problem is readily seen is the irradiation of patients during radiotherapy. The exposed part of the body is small Modelling the frequencies of chromosomal aberrations in peripheral lymphocytes of patients undergoing radiotherapy Witold Urbanik, Paweł Kukołowicz, Tomasz Kuszewski, Stanisław Góźdź, Andrzej Wójcik