title: Neon heavy charged particle radiotherapy of glioblastoma of the brain.
abstract: OBJECTIVE
  High-linear energy transfer (LET) radiation beams have potential applications in the treatment of glioblastoma, but have not yet demonstrated significant improvement in results. However, some patients have had local control of glioblastoma with high-LET irradiations such as neutrons and heavy charged particles.
  
  
  METHODS
  In this collaborative study, 15 patients were entered into a randomized protocol comparing two dose levels of 20 and 25 Gy in 4 weeks of neon ion irradiation. This trial was intended to determine the optimal neon dose in terms of survival and effects of radiation.
  
  
  RESULTS
  Fourteen patients were evaluable with no significant differences in median survival (13 and 14 months; p = NS) or median time to failure (7 and 9 months; p = NS) between the two dose arms. Three patients died of nontumor-related causes, of whom one (who died 19 months posttreatment) had autopsy confirmation of no tumor on pathological exam. The other two patients had stable magnetic resonance imaging scans at 6 and 22 months posttreatment.
  
  
  CONCLUSIONS
  Although the results did not demonstrate the optimal high-LET dose level, there is an intriguing effect in that two patients had control of glioblastoma until death at 19 and 22 months. This suggests that better conformation of the high-LET dose to the tumor with neutron capture therapy or dynamic conformal heavy charged particle therapy might control glioblastoma while minimizing brain damage from radiation.
authors.affiliation: Department of Radiation Oncology, University of California, Medical Center, San Francisco, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Castro
authors.forename: T L
authors.initials: TL
authors.lastname: Phillips
authors.forename: M
authors.initials: M
authors.lastname: Prados
authors.forename: P
authors.initials: P
authors.lastname: Gutin
authors.forename: D A
authors.initials: DA
authors.lastname: Larson
authors.forename: P L
authors.initials: PL
authors.lastname: Petti
authors.forename: I K
authors.initials: IK
authors.lastname: Daftari
authors.forename: J M
authors.initials: JM
authors.lastname: Collier
authors.forename: P
authors.initials: P
authors.lastname: Lillis-Hearne
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D002423:Cause of Death; D005260:Female; D005909:Glioblastoma / Q000401:mortality / Q000532:radiotherapy*; D006801:Humans; D018499:Linear Energy Transfer; D008297:Male; D008875:Middle Aged; D009356:Neon / Q000627:therapeutic use*
chemical_list: D009356:Neon