TY  - JOUR
AU  - Gillmann, Clarissa
AU  - Jäkel, Oliver
AU  - Karger, Christian
TI  - RBE-weighted doses in target volumes of chordoma and chondrosarcoma patients treated with carbon ion radiotherapy: Comparison of local effect models I and IV.
JO  - Radiotherapy and oncology
VL  - 141
SN  - 0167-8140
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - DKFZ-2019-02260
SP  - 234-238
PY  - 2019
N1  - 2019 Dec;141:234-238
AB  - To compare the relative biological effectiveness (RBE)-weighted dose distributions in the target volume of chordoma and chondrosarcoma patients when using two different versions of the local effect model (LEM I vs. IV) under identical conditions.The patient collective included 59 patients treated with 20 fractions of carbon ion radiotherapy for chordoma and low-grade chondrosarcoma of the skull base at the Helmholtzzentrum für Schwerionenforschung (GSI) in 2002 and 2003. Prescribed doses to the planning target volume (PTV) were 60 (n = 49), 66 (n = 2) and 70 (n = 8) Gy (RBE). The original treatment plans that were initially biologically optimized with LEM I, were now recalculated using LEM IV based on the absorbed dose distributions. The resulting RBE-weighted dose distributions were quantitatively compared to assess the clinical impact of LEM IV relative to LEM I in the target volume.LEM IV predicts 20-30 Gy (RBE) increased maximum doses as compared to LEM I, while minimum doses are decreased by 2-5 Gy (RBE). Population-based mean and median doses deviated by less than 2 Gy (RBE) between both models.LEM I and LEM IV-based RBE-weighted doses in the target volume may be significantly different. Replacing the applied model in patient treatments may therefore lead to local over- or underdosages in the tumor. If LEM IV is to be tested clinically, comparisons of the RBE-weighted dose distributions of both models are required for the individual patients to assess whether the LEM IV-plan would also be acceptable and prescribed dose as well as clinical outcome data have to be carefully reassessed.
LB  - PUB:(DE-HGF)16
C6  - pmid:31522880
DO  - DOI:10.1016/j.radonc.2019.08.006
UR  - https://inrepo02.dkfz.de/record/144835
ER  -