title: Carbon ion radiotherapy for unresectable sacral chordomas.
abstract: OBJECTIVE
  The purpose is to evaluate the efficacy and toxicity of carbon ion radiotherapy for unresectable sacral chordomas.
  
  
  METHODS
  We performed a retrospective analysis of 30 patients with unresectable sacral chordomas treated with carbon ion radiotherapy at the Heavy Ion Medical Accelerator in Chiba, Japan. Twenty-three patients presented with no prior treatment, and the remaining 7 patients had locally recurrent disease following previous surgical resection. The median clinical target volume was 546 cm(3). The applied carbon ion dose ranged from 52.8 to 73.6 GyE (gray equivalent, median 70.4) in 16 fixed fractions over 4 weeks.
  
  
  RESULTS
  At median follow-up of 30 months (range, 9 to 87 months), 26 patients were still alive and 24 patients remained continuously disease-free. Overall and cause-specific survival rates at 5 years were 52 and 94%, respectively. The overall local control rate at 5 years was 96%. Two patients experienced severe skin/soft tissue complications requiring skin grafts. No other treatment-related surgical interventions, including colostomy or urinary diversion, were carried out. All patients have remained ambulatory and able to stay at home after carbon ion radiotherapy.
  
  
  CONCLUSIONS
  Carbon ion radiotherapy is effective and safe in the management of patients with unresectable sacral chordomas and offers a promising alternative to surgery.
authors.affiliation: Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba.
authors.forename: Reiko
authors.initials: R
authors.lastname: Imai
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kamada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsuji
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yanagi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Baba
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Shingo
authors.initials: S
authors.lastname: Kato
authors.forename: Susumu
authors.initials: S
authors.lastname: Kandatsu
authors.forename: Jun-etsu
authors.initials: JE
authors.lastname: Mizoe
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Tsujii
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Tatezaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002250:Carbon Radioisotopes / Q000627:therapeutic use*; D002817:Chordoma / Q000532:radiotherapy*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D012189:Retrospective Studies; D012447:Sacrum; D013125:Spinal Neoplasms / Q000532:radiotherapy*; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D002250:Carbon Radioisotopes