@article{oai:repo.qst.go.jp:00086385,
 author = {Aoki, Shuri and Koto, Masashi and Ikawa, Hiroaki and Imai, Reiko and Tokuhiko, Omatsu and Shinoto, Makoto and Takiyama, Hirotoshi and Yamada, Shigeru and Tsuji, Hiroshi and Shuri, Aoki and Masashi, Koto and Hiroaki, Ikawa and Reiko, Imai and Tokuhiko, Omatsu and Makoto, Shinoto and Hirotoshi, Takiyama and Shigeru, Yamada and Hiroshi, Tsuji},
 journal = {Head & neck},
 month = {Jun},
 note = {Background: Chordoma is a rare, locally invasive neoplasm of the axial skeleton. Complete resection is often difficult, especially for the upper-cervical (C1-2) spine. We evaluated the efficacy and safety of carbon-ion radiotherapy (CIRT) for unresectable C1-2 chordoma.
Methods: Patients with C1-2 chordoma treated with definitive CIRT (60.8 Gy [RBE] in 16 fractions) were retrospectively analyzed. We evaluated OS, LC, PFS, and toxicity.
Results: Nineteen eligible patients all completed the planned course of CIRT. With the median follow-up 68 months (range: 29-144), median OS was 126 months (range: 36-NA). Five-year OS, LC, and PFS were 68.4% (95% CI, 42.8%-84.4%), 75.2% (46.1%-90.0%), and 64.1% (36.3%-82.3%), respectively. Regarding acute toxicity of grade ≥3, there was only one grade 3 mucositis. Late toxicity included radiation-induced myelitis (grade 3 in 1 patient; 5.3%), and compression fractures (n = 5; 26.3%).
Conclusions: High-dose CIRT is a promising treatment option for unresectable upper cervical chordoma.},
 title = {Long-term outcomes of high dose carbon-ion radiation therapy for unresectable upper cervical (C1-2) chordoma.},
 year = {2022}
}