Stochastic effects in a discrete RT model with critical behaviour

• Published in: Journal of physics. Conference series Vol. 633; no. 1; pp. 12089 - 12092
• Main Authors: Rodriguez-Perez, D, Sotolongo-Grau, O, Desco, M M, Antoranz, J C
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 21.09.2015
• Subjects: Fractionation; Physics; Radiation effects; Radiation therapy
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/633/1/012089

The effects of radiation on a tissue (being it healthy or cancerous) are well described by current linear-quadratic (LQ) radiobiological model for low absorbed doses around the 2 Gy often used in clinical fractionation. However, experimental data show a disagreement between the predicted and the observed effect of large doses. The Sotolongo et al. (2011) radiobiological (SRB) model, derived from Tsallis nonextensive entropy, has shown a good agreement with experiments for high absorbed doses, where LQ overestimates the dose required for a required effect. Other studies have reported a crossover in LQ model where its effects are underestimated for large doses. In this paper we develop a mechanistic version of the SRB model and show that it can reproduce both behaviors with a minimum set of assumptions. We compare the results of our simulations with some data reported in the literature. We also trivially adapt this model to fractionated radiotherapy and, in particular, to hypofractionation for which we draw some conclusions.