title: High-dose radiotherapy using helical tomotherapy for vertebral metastasis: early clinical outcomes and cord dose specification.
abstract: OBJECTIVE
  For several decades, radiotherapy has been widely used to treat metastatic vertebral tumors. This study was designed to assess the feasibility and early clinical outcomes of high-dose radiotherapy to treat such tumors, using helical tomotherapy.
  
  
  METHODS
  Between June 2009 and December 2011, 51 sites in 36 patients were treated with high-dose radiotherapy using helical tomotherapy for vertebral metastasis. Treatment outcomes and dosimetric analyses of spinal cord were retrospectively evaluated.
  
  
  RESULTS
  Median follow-up was 11.5 months (range, 6-34.6) for surviving patients. The median total dose and the number of fractions in the primary helical tomotherapy arm were 2700 cGy and 3 fractions, respectively. Actuarial 6-month local control rates were 85.7%, and symptomatic vertebral compression fractures developed in five patients after a median of 4.2 (range, 2.9-5.7) months. Among 13 patients with 19 metastatic sites who showed pre-treatment impairment in neurologic function, five patients (with seven sites) in whom symptoms were mild showed improvement in neuronal function. The median pre-treatment pain visual analog scale score of 7 decreased to a median of 3 after helical tomotherapy (P < 0.001) at a median of 1 month (range, 0.5-3.2) of follow-up. No significant morbidity developed during follow-up except for one grade 3 esophagitis.
  
  
  CONCLUSIONS
  The use of helical tomotherapy to treat metastatic vertebral tumors appears to be both safe and reliable in terms of local tumor control and early pain relief. Local progression and the risk of compression fracture in patients with pre-existing spinal instability remain the principal factors of limiting improved clinical and functional outcomes. Optimal dose-fractionation schemes and appropriate patient selection are required to achieve better outcomes with high-dose radiotherapy using helical tomotherapy.
authors.affiliation: Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 505 Banpo-dong, Seocho-gu, Seoul 137-701, Republic of Korea.
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.forename: Yoo Kang
authors.initials: YK
authors.lastname: Kwak
authors.forename: Song Mi
authors.initials: SM
authors.lastname: Jeong
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Song
authors.forename: Young Nam
authors.initials: YN
authors.lastname: Kang
authors.forename: Sang Nam
authors.initials: SN
authors.lastname: Lee
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Jang
authors.forename: Yeon Sil
authors.initials: YS
authors.lastname: Kim
authors.forename: Sei Chul
authors.initials: SC
authors.lastname: Yoon
authors.forename: Byung Ock
authors.initials: BO
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005260:Female; D005500:Follow-Up Studies; D050815:Fractures, Compression / Q000209:etiology; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D013125:Spinal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary*; D016896:Treatment Outcome
keywords: helical tomotherapy, spinal metastasis, stereotactic body radiotherapy, cord dose