title: Stereotactic interstitial brachytherapy for the treatment of oligodendroglial brain tumors.
abstract: OBJECTIVE
  We evaluated the treatment of oligodendroglial brain tumors with interstitial brachytherapy (IBT) using (125)iodine seeds ((125)I) and analyzed prognostic factors.
  
  
  METHODS
  Between January 1991 and December 2010, 63 patients (median age 43.3 years, range 20.8-63.4 years) suffering from oligodendroglial brain tumors were treated with (125)I IBT either as primary, adjuvantly after incomplete resection, or as salvage therapy after tumor recurrence. Possible prognostic factors influencing disease progression and survival were retrospectively investigated.
  
  
  RESULTS
  The actuarial 2-, 5-, and 10-year overall and progression-free survival rates after IBT for WHO II tumors were 96.9, 96.9, 89.8 % and 96.9, 93.8, 47.3 %; for WHO III tumors 90.3, 77, 54.9 % and 80.6, 58.4, 45.9 %, respectively. Magnetic resonance imaging demonstrated complete remission in 2 patients, partial remission in 13 patients, stable disease in 17 patients and tumor progression in 31 patients. Median time to progression for WHO II tumors was 87.6 months and for WHO III tumors 27.8 months. Neurological status improved in 10 patients and remained stable in 20 patients, while 9 patients deteriorated. There was no treatment-related mortality. Treatment-related morbidity was transient in 11 patients. WHO II, KPS ≥ 90 %, frontal location, and tumor surface dose > 50 Gy were associated with increased overall survival (p ≤ 0.05). Oligodendroglioma and frontal location were associated with a prolonged progression-free survival (p ≤ 0.05).
  
  
  CONCLUSIONS
  Our study indicates that IBT achieves local control rates comparable to surgery and radio-/chemotherapy treatment, is minimally invasive, and safe. Due to the low rate of side effects, IBT may represent an attractive option as part of a multimodal treatment schedule, being supplementary to microsurgery or as a salvage therapy after chemotherapy and conventional irradiation.
authors: Department of Stereotaxy and Functional Neurosurgery, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. elmajdoubf@kliniken-koeln.de.|Department of Stereotaxy and Functional Neurosurgery, Center of Neurosurgery, Cologne-Merheim Medical Center (CMMC), University of Witten/Herdecke, Ostmerheimer Strasse 200, 51109, Cologne, Germany. elmajdoubf@kliniken-koeln.de.
authors: Faycal
authors: F
authors: El Majdoub
authors: Department of Stereotaxy and Functional Neurosurgery, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. neudorferc@kliniken-koeln.de.|Department of Stereotaxy and Functional Neurosurgery, Center of Neurosurgery, Cologne-Merheim Medical Center (CMMC), University of Witten/Herdecke, Ostmerheimer Strasse 200, 51109, Cologne, Germany. neudorferc@kliniken-koeln.de.
authors: Clemens
authors: C
authors: Neudorfer
authors: Department of Neuropathology, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. tobias.blau@uk-koeln.de.
authors: Tobias
authors: T
authors: Blau
authors: Institute of Statistics, Informatics and Epidemiology, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. martin.hellmich@uk-koeln.de.
authors: Martin
authors: M
authors: Hellmich
authors: Department of Stereotaxy and Functional Neurosurgery, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. christian.buehrle@uk-koeln.de.
authors: Christian
authors: C
authors: Bührle
authors: Department of Neuropathology, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. martina.deckert@uk-koeln.de.
authors: Martina
authors: M
authors: Deckert
authors: Department of Stereotaxy and Functional Neurosurgery, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. volkersturm@online.de.|Department of Neurosurgery, University Hospital of Wurzburg, Josef-Schneider-Strasse 11, 97080, Würzburg, Germany. volkersturm@online.de.
authors: Volker
authors: V
authors: Sturm
authors: Department of Stereotaxy and Functional Neurosurgery, University Hospital of Cologne, Kerpener Strasse 62, 50938, Cologne, Germany. maaroufm@kliniken-koeln.de.|Department of Stereotaxy and Functional Neurosurgery, Center of Neurosurgery, Cologne-Merheim Medical Center (CMMC), University of Witten/Herdecke, Ostmerheimer Strasse 200, 51109, Cologne, Germany. maaroufm@kliniken-koeln.de.
authors: Mohammad
authors: M
authors: Maarouf
mesh_terms: D000328:Adult; D001918:Brachytherapy / Q000379:methods*; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D003131:Combined Modality Therapy; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009837:Oligodendroglioma / Q000401:mortality / Q000532:radiotherapy*; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D016879:Salvage Therapy; D013238:Stereotaxic Techniques; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes
keywords: Disease-free survival; Iodine-125; Local control; Oligoastrocytoma; Oligodendroglioma