title: Management of patients with recurrent glioblastoma using hypofractionated stereotactic radiotherapy.
abstract: BACKGROUND
  Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. The chance of cure is very limited due to treatment-refractory disease course with frequent recurrences despite aggressive multimodality management. In this retrospective study, we evaluated treatment outcomes of hypofractionated stereotactic radiotherapy (HFSRT) in the management of recurrent GBM and report our single-center experience.
  
  
  METHODS
  Twenty-eight patients receiving HFSRT for recurrent GBM between September 2008 and February 2014 were retrospectively assessed. Total radiotherapy dose was 25 Gy delivered in 5 fractions over 5 consecutive days for all patients. High-precision, image-guided volumetric modulated arc therapy was delivered with a linear accelerator using 6-MV photons using the frameless technique. Analyzed prognostic factors were age, gender, Karnofsky performance status (KPS), tumor location, planning target volume (PTV) size, overall survival (OS), progression-free survival (PFS), time interval between completion of treatment with Stupp protocol at primary diagnosis and recurrence.
  
  
  RESULTS
  Median follow-up time was 42 months (range 2-68). Median time interval between primary chemoradiotherapy and HFSRT was 11.2 months (range 4-57.9). Median OS and PFS calculated from reirradiation was 10.3 months and 5.8 months, respectively. Longer interval between initial treatment and recurrence (p = 0.01), smaller PTV size (p = 0.001), KPS ≥70 (p = 0.005) and younger age (p = 0.004) were associated with longer OS on statistical analysis.
  
  
  CONCLUSIONS
  HFSRT offers a feasible and effective salvage treatment option for recurrent GBM management. Prognostic factors associated with longer OS in our study were longer interval between initial treatment and recurrence, smaller PTV size, KPS ≥70 and younger age.
authors: Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara - Turkey.
authors: Ferrat
authors: F
authors: Dincoglan
authors: Murat
authors: M
authors: Beyzadeoglu
authors: Omer
authors: O
authors: Sager
authors: Selcuk
authors: S
authors: Demiral
authors: Hakan
authors: H
authors: Gamsiz
authors: Bora
authors: B
authors: Uysal
authors: Cuneyt
authors: C
authors: Ebruli
authors: Mustafa
authors: M
authors: Akin
authors: Kaan
authors: K
authors: Oysul
authors: Sait
authors: S
authors: Sirin
authors: Bahar
authors: B
authors: Dirican
mesh_terms: D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D005909:Glioblastoma / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy / Q000601:surgery*; D011379:Prognosis; D016634:Radiosurgery / Q000379:methods; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016879:Salvage Therapy / Q000379:methods*; D016896:Treatment Outcome