title: Dose escalation using helical tomotherapy improves local control in spine metastases from primary hepatic malignancies.
abstract: OBJECTIVE
  This study was designed to reveal the prognostic significance of dose-escalated radiotherapy with tomotherapy in local control for spine metastases of primary hepatic tumours.
  
  
  METHODS
  From April 2006 to May 2012, 23 hepatocellular carcinoma patients and 7 intrahepatic cholangiocellular carcinoma patients (total 30 patients, 42 spinal lesions) were treated for metastatic spine lesions with helical tomotherapy (HT). The gross tumour volume (GTV) was defined as a tumour evident from computed tomography and magnetic resonance imaging. Median values were as follows: GTV total dose of 48 Gy (range 21-51), fraction size of 6 Gy (range 3-8) and eight fractions (range 3-17). Pain response was checked according to visual analogue scale (from 0 to 10).
  
  
  RESULTS
  The median follow-up was 5.6 months. Six events of local failure occurred, including five lesions in which spinal canals were involved at radiotherapy. Local control rate at 3 months was 86.6%. Biological equivalent dose (BED) was correlated with local control (AUC = 0.833). Higher BED (>56.0 Gy10 ) was associated with increased local control (P = 0.004). The median time to local progression in patients receiving ≤56.0 Gy10 and >56.0 Gy10 were 3 and 20.8 months respectively. Dose escalation (BED > 56.0 Gy10 ) was also associated with improved progression-free survival (median 14.7 vs. 2.8 months, P = 0.010). Pain reduction was observed in 90.9% (20/22) of patients with painful bone metastases.
  
  
  CONCLUSIONS
  Dose-escalated radiotherapy (BED > 56.0 Gy10 ) using HT improved local control in spinal metastases of hepatic malignancies.
authors.affiliation: Department of Radiation Oncology, Yonsei University Health System, Seoul, South Korea.
authors.forename: Yunseon
authors.initials: Y
authors.lastname: Choi
authors.forename: Junwon
authors.initials: J
authors.lastname: Kim
authors.forename: Ikjae
authors.initials: I
authors.lastname: Lee
authors.forename: Jinsil
authors.initials: J
authors.lastname: Seong
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D018281:Cholangiocarcinoma / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D050397:Radiotherapy, Intensity-Modulated; D013115:Spinal Canal; D013125:Spinal Neoplasms / Q000175:diagnosis / Q000532:radiotherapy* / Q000556:secondary*; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome