title: Monte Carlo as a tool to evaluate the effect of different lung densities on radiotherapy dose distribution.
abstract: This study aims at evaluating the effects of different lung densities on dose distribution after irradiation at different field sizes, by comparing experimental measurements, GEANT4 Monte Carlo (MC) simulations and two TPS calculation algorithms on ad hoc phantoms. Irradiations were performed with a Varian Clinac 2100 C/D with a nominal energy of 6 MV. Dosimetric experimental measurements were obtained with radiochromic films. A model based on GEANT4 MC code was developed to simulate both the accelerator and the phantoms. Results of dose distribution show an acceptable agreement between MC simulations and experimental measurements, both in the tumour-equivalent region and in the normal tissue-equivalent ones. On the opposite, results vary among the TPS algorithms, especially in regions of lung-equivalent material at low density, but also at the interface between lung- and tumour-equivalent materials.
authors.affiliation: Technology and Health Department, Istituto Superiore di Sanità (Italian National Institute of Health), Viale Regina Elena, 299-00161, Rome, Italy INFN, Joint group of Istituto Superiore di Sanità, Rome, Italy barbara.caccia@iss.it.
authors.forename: B
authors.initials: B
authors.lastname: Caccia
authors.affiliation: INAIL, Rome, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Andenna
authors.affiliation: Istituto Regina Elena, Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Iaccarino
authors.affiliation: Istituto Regina Elena, Rome, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Landoni
authors.affiliation: Istituto Regina Elena, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Soriani
authors.affiliation: Technology and Health Department, Istituto Superiore di Sanità (Italian National Institute of Health), Viale Regina Elena, 299-00161, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Occhigrossi
authors.affiliation: Technology and Health Department, Istituto Superiore di Sanità (Italian National Institute of Health), Viale Regina Elena, 299-00161, Rome, Italy INFN, Joint group of Istituto Superiore di Sanità, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Esposito
authors.affiliation: Technology and Health Department, Istituto Superiore di Sanità (Italian National Institute of Health), Viale Regina Elena, 299-00161, Rome, Italy INFN, Joint group of Istituto Superiore di Sanità, Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Petetti
authors.affiliation: Technology and Health Department, Istituto Superiore di Sanità (Italian National Institute of Health), Viale Regina Elena, 299-00161, Rome, Italy INFN, Joint group of Istituto Superiore di Sanità, Rome, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Valentini
authors.affiliation: INFN, Joint group of Istituto Superiore di Sanità, Rome, Italy Istituto Regina Elena, Rome, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Strigari
mesh_terms: D000465:Algorithms; D006801:Humans; D008168:Lung / Q000528:radiation effects*; D008175:Lung Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D008962:Models, Theoretical; D009010:Monte Carlo Method; D010315:Particle Accelerators; D019047:Phantoms, Imaging; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012119:Respiration; D012984:Software