TY  - JOUR
AU  - Unkelbach, Jan
AU  - Bangert, Mark
AU  - De Amorim Bernstein, Karen
AU  - Andratschke, Nicolaus
AU  - Guckenberger, Matthias
TI  - Optimization of combined proton-photon treatments.
JO  - Radiotherapy and oncology
VL  - 128
IS  - 1
SN  - 0167-8140
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - DKFZ-2018-01343
SP  - 133 - 138
PY  - 2018
AB  - Proton treatment slots are a limited resource. Therefore, we consider combined proton-photon treatments in which most fractions are delivered with photons and only a few with protons. We demonstrate how both modalities can be combined to optimally capitalize on the proton's ability to reduce normal tissue dose.An optimal combined treatment must account for fractionation effects. We therefore perform simultaneous optimization of intensity-modulated proton (IMPT) and photon (IMRT) plans based on their cumulative biologically effective dose (BED). We demonstrate the method for a sacral chordoma patient, in whom the gross tumor volume (GTV) abuts bowel and rectum.In an optimal combination, proton and photon fractions deliver similar doses to bowel and rectum to protect these dose-limiting normal tissues through fractionation. However, proton fractions deliver, on average, higher doses to the GTV. Thereby, the photon dose bath is reduced. An optimized 30-fraction treatment with 10 IMPT fractions achieved more than 50
LB  - PUB:(DE-HGF)16
C6  - pmid:29370987
DO  - DOI:10.1016/j.radonc.2017.12.031
UR  - https://inrepo02.dkfz.de/record/136905
ER  -