@article{oai:repo.qst.go.jp:00046493,
 author = {Fossati, Piero and Molinelli, Silvia and Matsufuji, Naruhiro and Mizoe, Junetsu and Hasegawa, Azusa and Imai, Reiko and Kamada, Tadashi and Tsujii, Hirohiko and et.al and Ｆｏｓｓａｔｉ Ｐｉｅｒｏ and Ｍｏｌｉｎｅｌｌｉ Ｓｉｌｖｉａ and 松藤 成弘 and 溝江 純悦 and 長谷川 安都佐 and 今井 礼子 and 鎌田 正 and 辻井 博彦},
 issue = {22},
 journal = {Physics in Medicine and Biology},
 month = {Oct},
 note = {In carbon ion radiotherapy there is an urgent clinical need to develop objective
tools for the conversion of relative biological effectiveness (RBE)-weighted
doses based on different models. In this work we introduce a clinically oriented
method to compare NIRS-based and LEM-based GyE systems, minimizing
differences in physical dose distributions between treatment plans. Carbon ion
plans were optimized on target volumes of cubic and spherical shapes, for RBEweighted dose prescription levels ranging from 3.6 to 4.4 GyE. Plans were
calculated for target sizes from 4 to 12 cm defining three beam geometries:
single beam, opposed beam and orthogonal beam configurations. The two
treatment planning systems currently employed in clinical practice were used,
providing the NIRS-based and LEM-based GyE calculations. Physical dose
distributions of NIRS-based and LEM-based treatment plans were compared.
LEM-based prescription doses that minimize differences in physical dose
distributions between the two systems were found. These doses were compared
with the mean RBE-weighted dose obtained with a Monte Carlo code (FLUKA)
interfaced with LEM I. In the investigated dose range, LEM-based RBEweighted
prescription doses, that minimize differences with NIRS plans, should
be higher than NIRS reported prescription doses. The optimal dose depends on
target size, shape and position, number of beams and dose level. The opposed
beam configuration resulted in the smallest average prescription dose difference
(0.45 +/- 0.09 GyE). The second approach of recalculating NIRS RBE-weighted
dose with a Monte Carlo code interfaced with LEM resulted in no significant
difference with the results obtained from the planning study. The delivery of a
voxel by voxel iso-effective plan, if different RBE models are employed, is not
feasible; it is however possible to minimize differences in a treatment plan with
the simple approach presented here. Dose prescription ultimately represents a
clinical task under the responsibility of the radiation oncologist, the presented
analysis intends to be a quantitative and objective way to assist the clinical
decision.},
 pages = {7543--7554},
 title = {Dose prescription in carbon ion radiotherapy: a planning study to compare NIRS and LEM approaches with a clinically-oriented strategy},
 volume = {57},
 year = {2012}
}