title: A mechanistic description of radiation-induced damage to normal tissue and its healing kinetics.
abstract: We introduce a novel mechanistic model of the yield of tissue damage at the end of radiation treatment and of the subsequent healing kinetics. We find explicit expressions for the total number of functional proliferating cells as well as doomed (functional but non-proliferating) cells as a function of time post treatment. This leads to the possibility of estimating-for any given cohort of patients undergoing radiation therapy-the probability distribution of those kinetic parameters (e.g. proliferation rates) that determine times to injury onset and ensuing resolution. The model is suitable for tissues with simple duplication organization, meaning that functionally competent cells are also responsible for tissue renewal or regeneration following injury. An extension of the model to arbitrary temporal patterns of dose rate is presented. To illustrate the practical utility of the model, as well as its limitations, we apply it to data on the time course of urethral toxicity following fractionated radiation treatment and brachytherapy for prostate cancer.
authors: Department of Mathematics, Idaho State University, 921 S. 8th Avenue, Stop 8085, Pocatello, ID 83209-8085, USA.
authors: Leonid
authors: L
authors: Hanin
authors: Marco
authors: M
authors: Zaider
mesh_terms: D000465:Algorithms; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D049109:Cell Proliferation / Q000528:radiation effects*; D015331:Cohort Studies; D019583:Dose Fractionation, Radiation; D006801:Humans; D007700:Kinetics; D016013:Likelihood Functions; D008297:Male; D008954:Models, Biological; D011336:Probability; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D013997:Time Factors; D014521:Urethra / Q000528:radiation effects*