title: Proton beam therapy versus conformal photon radiation therapy for childhood craniopharyngioma: multi-institutional analysis of outcomes, cyst dynamics, and toxicity.
abstract: OBJECTIVE
  We compared proton beam therapy (PBT) with intensity modulated radiation therapy (IMRT) for pediatric craniopharyngioma in terms of disease control, cyst dynamics, and toxicity.
  
  
  METHODS
  We reviewed records from 52 children treated with PBT (n=21) or IMRT (n=31) at 2 institutions from 1996-2012. Endpoints were overall survival (OS), disease control, cyst dynamics, and toxicity.
  
  
  RESULTS
  At 59.6 months' median follow-up (PBT 33 mo vs IMRT 106 mo; P<.001), the 3-year outcomes were 96% for OS, 95% for nodular failure-free survival and 76% for cystic failure-free survival. Neither OS nor disease control differed between treatment groups (OS P=.742; nodular failure-free survival P=.546; cystic failure-free survival P=.994). During therapy, 40% of patients had cyst growth (20% requiring intervention); immediately after therapy, 17 patients (33%) had cyst growth (transient in 14), more commonly in the IMRT group (42% vs 19% PBT; P=.082); and 27% experienced late cyst growth (32% IMRT, 19% PBT; P=.353), with intervention required in 40%. Toxicity did not differ between groups. On multivariate analysis, cyst growth was related to visual and hypothalamic toxicity (P=.009 and .04, respectively). Patients given radiation as salvage therapy (for recurrence) rather than adjuvant therapy had higher rates of visual and endocrine (P=.017 and .024, respectively) dysfunction.
  
  
  CONCLUSIONS
  Survival and disease-control outcomes were equivalent for PBT and IMRT. Cyst growth is common, unpredictable, and should be followed during and after therapy, because it contributes to late toxicity. Delaying radiation therapy until recurrence may result in worse visual and endocrine function.
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.
authors: Andrew J
authors: AJ
authors: Bishop
authors: Department of Radiation Oncology, Baylor College of Medicine, Houston, Texas.
authors: Brad
authors: B
authors: Greenfield
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.
authors: Anita
authors: A
authors: Mahajan
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas; Department of Radiation Oncology, Baylor College of Medicine, Houston, Texas.
authors: Arnold C
authors: AC
authors: Paulino
authors: Department of Pediatrics, Texas Children's Cancer and Hematology Center, Baylor College of Medicine, Houston, Texas.
authors: M Fatih
authors: MF
authors: Okcu
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.
authors: Pamela K
authors: PK
authors: Allen
authors: Department of Pediatrics, Texas Children's Cancer and Hematology Center, Baylor College of Medicine, Houston, Texas.
authors: Murali
authors: M
authors: Chintagumpala
authors: Section of Psychology, Texas Children's Cancer and Hematology Center, Baylor College of Medicine, Houston, Texas.
authors: Lisa S
authors: LS
authors: Kahalley
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.
authors: Mary F
authors: MF
authors: McAleer
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.
authors: Susan L
authors: SL
authors: McGovern
authors: Department of Neurosurgery, Texas Children's Cancer and Hematology Center, Baylor College of Medicine, Houston, Texas.
authors: William E
authors: WE
authors: Whitehead
authors: Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas. Electronic address: dgrossha@mdanderson.org.
authors: David R
authors: DR
authors: Grosshans
mesh_terms: D002648:Child; D003397:Craniopharyngioma / Q000401:mortality / Q000532:radiotherapy*; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D010911:Pituitary Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D061766:Proton Therapy / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D016896:Treatment Outcome