title: Reirradiation of Pediatric Tumors Using Hypofractionated Stereotactic Radiotherapy.
abstract: This study aimed to evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy for reirradiation of recurrent pediatric tumors.
  
  
  
  The study included 23 pediatric patients who were reirradiated using hypofractionated stereotactic radiotherapy in the radiation oncology department between January 2008 and November 2013. In total, 33 tumors were treated-27 (82%) cranial and 6 (18%) extracranial. Hypofractionated stereotactic radiotherapy was administered due to recurrent disease in 31 (94%) tumors and residual disease in 2 (6%) tumors. The median total dose was 25 Gy (range: 15-40 Gy), and the median follow-up was 20 months (range: 2-68 months).
  
  
  
  The 1-year and 2-year local control rates in the entire study population were 42% and 31%, respectively. The median local control time was 11 months (range: 0-54 months) following hypofractionated stereotactic radiotherapy. The patients with tumor response after hypofractionated stereotactic radiotherapy had significantly longer local control than the patients with post-hypofractionated stereotactic radiotherapy tumor progression (21 vs 3 months, P < .001). Tumor volume <1.58 cm3was correlated (not significantly) with better local control (23 vs 7 months, P = .064).
  
  
  
  Reirradiation of pediatric tumors using hypofractionated stereotactic radiotherapy is a safe and effective therapeutic approach. This treatment modality should be considered as a treatment option in selected pediatric patients.
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Melis
authors.initials: M
authors.lastname: Gultekin
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Cengiz
authors.affiliation: 2 Department of Radiation Oncology, School of Medicine, Koç University, Istanbul, Turkey.
authors.forename: Duygu
authors.initials: D
authors.lastname: Sezen
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Faruk
authors.initials: F
authors.lastname: Zorlu
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Ferah
authors.initials: F
authors.lastname: Yildiz
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Gozde
authors.initials: G
authors.lastname: Yazici
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Pervin
authors.initials: P
authors.lastname: Hurmuz
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Ozyigit
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Fadil
authors.initials: F
authors.lastname: Akyol
authors.affiliation: 1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Gurkaynak
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D019583:Dose Fractionation, Radiation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local; D009369:Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000532:radiotherapy*; D011379:Prognosis; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods; D011879:Radiotherapy Dosage; D000069475:Re-Irradiation; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: hypofractionation; pediatric tumors; reirradiation; stereotactic body radiotherapy; stereotactic radiotherapy