@article{oai:repo.qst.go.jp:00047676,
 author = {Fukahori, Mai and Matsufuji, Naruhiro and Himukai, Takeshi and Kanematsu, Nobuyuki and Mizuno, Hideyuki and Fukumura, Akifumi and Tsuji, Hiroshi and Kamada, Tadashi and 深堀 麻衣 and 松藤 成弘 and 日向 猛 and 兼松 伸幸 and 水野 秀之 and 福村 明史 and 辻 比呂志 and 鎌田 正},
 issue = {1},
 journal = {Radiotherapy and Oncology},
 month = {Jan},
 note = {Purpose: The aim of this study was to estimate normal tissue complication probability (NTCP) parameters
for late rectal complications after carbon ion radiotherapy (C-ion RT) for prostate cancer.
Methods and materials: A total of 163 patients were used to derive NTCP parameters. These patients were
treated with relative biological effectiveness (RBE)-weighted dose ranging from 57.6 Gy (RBE) up to 72 Gy
(RBE) and included in dose escalation trials. The Lyman–Kutcher–Burman (LKB) model was used and the
model parameters were fit to the relation between dose and complication observed after C-ion RT.
Results: The resulting NTCP parameters were the volume effect parameter; n = 0.035 (95% CI: 0.024–
0.047), the steepness of the NTCP curve; m = 0.10 (0.084–0.13), the tolerance dose associated with 50%
probability of complication; TD50 = 63.6 Gy (RBE) (61.8–65.4 Gy (RBE)) for GradeP1, n = 0.012
(0.0050–0.023), m = 0.046 (0.033–0.062), TD50 = 69.1 Gy (RBE) (67.6–70.9 Gy (RBE)) for GradeP2.
Conclusion: A new set of rectal NTCP parameters in C-ion RT was determined. The rather small n values
suggest that the rectum was consistent with being strictly serial organ. The new derived parameter values
facilitate estimation of rectal NTCP in C-ion RT.},
 pages = {136--140},
 title = {Estimation of late rectal normal tissue complication probability parameters in carbon ion therapy for prostate cancer},
 volume = {118},
 year = {2016}
}