Water versus DNA: New Insights into Proton Track-Structure Modeling in Radiobiology and Radiotherapy

C. CHAMPION; M. QUINTO; J. M. MONTI; M. GALASSI; P. WECK; O. FOJON; J. HANSSEN; R. RIVAROLA

PHYSICS IN MEDICINE AND BIOLOGY

IOP PUBLISHING LTD

Lugar: Londres; Año: 2015

0031-9155

Water vapor is a common surrogate of DNA for modeling the proton-induced ionizing processes in living tissueexposed to radiations. The present study aims at scrutinizing the validity of this approximation and then revealing new insights intoproton-induced energy transfers by a comparative analysis between water and realistic biological medium. In this context, self-consistent quantum mechanical modeling of the ionization and electron capture processes is reported within the continuum distortedwave-eikonal initial state framework for both isolated water molecules and DNA components impacted by proton beams. Theirrespective probability of occurrence, expressed in terms of total cross sections, and their energetic signature (potential and kinetic)are assessed in order to clearly emphasize the differences existing between realistic building blocks of living matter and the contro-verted water-medium surrogate. Evident knock-on effects in radiobiology and radiotherapy will be discussed in particular in viewof the refinement of treatment planning aiming at better radiotherapy strategies.