title: Outcome and toxicity profile of salvage low-dose-rate iodine-125 stereotactic brachytherapy in recurrent high-grade gliomas.
abstract: BACKGROUND
  The aim of this study was to provide an outcome and toxicity profile of salvage low-dose-rate iodine-125 (I-125) stereotactic brachytherapy (SBT) in patients with small, circumscribed malignant glioma recurrences.
  
  
  METHODS
  Patients with malignant glioma recurrences consecutively undergoing salvage SBT from 2003 to 2011 were identified from our prospective tumor database. SBT was considered a potentially suitable treatment strategy for adult mostly multimodally pretreated patients (Karnofsky score of ≥ 70) with biopsy-proven, circumscribed, small (diameter ≤ 3.5 cm) recurrences. Exclusively temporary I-125 seeds were used (reference dose: 50 Gy, dose rate: < 15 cGy/h). Study endpoints were time-to-treatment failure (TTF) after SBT, postrecurrence survival (PRS), and toxicity. Survival was assessed with the Kaplan-Meier method. Adverse events were categorized according to the RTOG/EORTC classification. Prognostic factors were obtained from proportional hazards models.
  
  
  RESULTS
  Sixty-eight patients (28 WHO grade III, 40 WHO grade IV gliomas) were included. Fifty-nine patients had previously received external beam radiation. Median TTF and PRS were 8.3 months and 13.4 months, respectively. TTF and PRS were longer for grade III gliomas than for glioblastomas (15.0 vs. 6.2 months and 28.1 vs. 9.3 months, respectively). Patients with grade III tumors were younger (p = 0.002). Favorable factors for TTF and PRS were age ≤ 50 years and a methylated O(6)-methylguanine-DNA methyltransferase (MGMT)-promoter. Alternative models including tumor grade instead of age reached a similar good fit. Three patients suffered from grade I, one from grade II, and two from grade IV toxicity.
  
  
  CONCLUSIONS
  Salvage SBT is feasible and safe even after previously performed external beam radiation. Favorable outcome measurements in particular for grade III recurrences deserve further prospective evaluation.
authors: Department of Neurosurgery, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany.
authors: Christoph
authors: C
authors: Schwartz
authors: Department of Neurosurgery, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany.
authors: Alexander
authors: A
authors: Romagna
authors: Department of Neurosurgery, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany.
authors: Niklas
authors: N
authors: Thon
authors: Department of Radiation-Oncology, Ludwig-Maximilians-University, Munich, Germany.
authors: Maximilian
authors: M
authors: Niyazi
authors: Department of Radiation-Oncology, Ludwig-Maximilians-University, Munich, Germany.
authors: Juliana
authors: J
authors: Watson
authors: Department of Radiation-Oncology, Ludwig-Maximilians-University, Munich, Germany.
authors: Claus
authors: C
authors: Belka
authors: Department of Neurosurgery, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany.
authors: Jörg-Christian
authors: JC
authors: Tonn
authors: Department of Neurosurgery, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany. friedrich-wilhelm.kreth@med.uni-muenchen.de.
authors: Friedrich-Wilhelm
authors: FW
authors: Kreth
authors: Department of Radiation-Oncology, Ludwig-Maximilians-University, Munich, Germany.
authors: Silke Birgit
authors: SB
authors: Nachbichler
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects*; D001932:Brain Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D005909:Glioblastoma / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D011879:Radiotherapy Dosage
chemical_list: D007457:Iodine Radioisotopes
keywords: Brachytherapy; High-grade glioma; Postrecurrence survival