title: Fractionated stereotactic radiotherapy using gamma unit after hyperbaric oxygenation on recurrent high-grade gliomas.
abstract: BACKGROUND
  To reduce this complication and to enhance the radiation effect to hypoxic cells of high-grade gliomas, the authors performed noninvasive fractionated stereotactic radiotherapy (FSRT) using a Gamma unit combined with hyperbaric oxygen (HBO) therapy for the treatment of recurrent disease.
  
  
  METHODS
  Twenty-five consecutive patients who had previously received radiotherapy with chemotherapy for recurrent high-grade gliomas, including 14 patients with anaplastic astrocytoma (AA) and 11 with glioblastoma multiforme (GBM), underwent Gamma FSRT immediately after HBO therapy (2.5 atmospheres absolute for 60 min). The Gamma FSRT was repeatedly performed using a relocatable head cast. Median tumor volume was 8.7 cc (range, 1.7-159.3 cc), and the median total radiation dose was 22 Gy (range, 18-27 Gy) to the tumor margin in 8 fractions.
  
  
  RESULTS
  Actuarial median survival time after FSRT was 19 months for patients with AA and 11 months for patients with GBM, which was significantly different (P = 0.012, log-rank test). Two patients underwent subsequent second FSRT for regional or remote recurrence. Seven patients (28%) underwent subsequent craniotomies and resections at a mean of 8.4 months after FSRT treatment, and 4 of them had radiation effects without viable cells and remained alive for 50-78 months.
  
  
  CONCLUSIONS
  Gamma FSRT after HBO therapy appears to confer a survival benefit for patients with recurrent high-grade gliomas and warrants further investigation.
authors.affiliation: Division of Hyperbaric Medicine and Department of Neurosurgery, University Hospital of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, 807-8555, Kitakyushu, Japan. k-kohshi@clnc.uoeh-u.ac.jp
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Kohshi
authors.forename: Haruaki
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Ai
authors.initials: A
authors.lastname: Nakahara
authors.forename: Takahiko
authors.initials: T
authors.lastname: Katoh
authors.forename: Masashi
authors.initials: M
authors.lastname: Takagi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000401:mortality / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D005910:Glioma / Q000401:mortality / Q000628:therapy*; D006801:Humans; D006931:Hyperbaric Oxygenation; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery*; D016634:Radiosurgery; D016019:Survival Analysis; D016896:Treatment Outcome