title: Clinical Outcomes Among Children With Standard-Risk Medulloblastoma Treated With Proton and Photon Radiation Therapy: A Comparison of Disease Control and Overall Survival.
abstract: OBJECTIVE
  The purpose of this study was to compare long-term disease control and overall survival between children treated with proton and photon radiation therapy (RT) for standard-risk medulloblastoma.
  
  
  METHODS
  This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS), and patterns of failure were compared between the 2 cohorts.
  
  
  RESULTS
  Median (range) age was 6 years old at diagnosis (3-21 years) for proton patients versus 8 years (3-19 years) for photon patients (P=.011). Cohorts were similar with respect to sex, histology, extent of surgical resection, craniospinal irradiation (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18-27 Gy) and a boost of 30.6 Gy (27-37.8 Gy). Median follow-up time is 6.2 years (95% confidence interval [CI]: 5.1-6.6 years) for proton patients versus 7.0 years (95% CI: 5.8-8.9 years) for photon patients. There was no significant difference in RFS or OS between patients treated with proton versus photon RT; 6-year RFS was 78.8% versus 76.5% (P=.948) and 6-year OS was 82.0% versus 87.6%, respectively (P=.285). On multivariate analysis, there was a trend for longer RFS with females (P=.058) and higher CSI dose (P=.096) and for longer OS with females (P=.093). Patterns of failure were similar between the 2 cohorts (P=.908).
  
  
  CONCLUSIONS
  Disease control with proton and photon radiation therapy appears equivalent for standard risk medulloblastoma.
authors.affiliation: Departments of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia.
authors.forename: Bree R
authors.initials: BR
authors.lastname: Eaton
authors.affiliation: Departments of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia.
authors.forename: Natia
authors.initials: N
authors.lastname: Esiashvili
authors.affiliation: Department of Biostatistics and Bioinformatics, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Sungjin
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Weyman
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Lauren T
authors.initials: LT
authors.lastname: Thornton
authors.affiliation: Department of Pediatrics, Aflac Cancer and Blood Disorders Center, Atlanta, Georgia.
authors.forename: Claire
authors.initials: C
authors.lastname: Mazewski
authors.affiliation: Department of Pediatrics, Aflac Cancer and Blood Disorders Center, Atlanta, Georgia.
authors.forename: Tobey
authors.initials: T
authors.lastname: MacDonald
authors.affiliation: Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: David
authors.initials: D
authors.lastname: Ebb
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Shannon M
authors.initials: SM
authors.lastname: MacDonald
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Tarbell
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts. Electronic address: tyock@partners.org.
authors.forename: Torunn I
authors.initials: TI
authors.lastname: Yock
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D002528:Cerebellar Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008527:Medulloblastoma / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local; D017785:Photons / Q000627:therapeutic use*; D061766:Proton Therapy / Q000379:methods* / Q000401:mortality; D012737:Sex Factors; D017211:Treatment Failure; D055815:Young Adult