title: CNS irradiation in pediatric acute myleoid leukemia: equal results by 12 or 18 Gy in studies AML-BFM98 and 2004.
abstract: BACKGROUND
  The impact of preventive central nervous system irradiation (CNS-RT) in childhood acute myeloid leukemia (AML) is still discussed. As results of study AML-BFM87 revealed an increased risk for relapse when CNS-RT was not performed, studies AML-BFM98 and -2004 randomized CNS-RT of 18 or 12 Gy in order to evaluate the efficacy of the lower dose and to reduce late effects.
  
  
  METHODS
  To achieve a power of 80% for non-inferiority (range 11%) 240 patients per group were required. Out of 722 eligible patients, 486 patients <18 years were randomized to receive 12 Gy (n = 249) or 18 Gy (n = 237). Since this was a non-inferiority study, the analysis was performed for patients as treated (12 Gy: n = 252 and 18 Gy: n = 219).
  
  
  RESULTS
  Five-year survival, event-free survival and cumulative incidence of relapse were similar in patients who received 12 or 18 Gy, respectively (82 ± 3% vs. 79 ± 3%, 68 ± 3% vs. 63 ± 3%, and 30 ± 3% vs. 34 ± 3%). The lower limit of the one-sided confidence interval for the -5% difference in 5-years pEFS was 2%. There were six relapses with CNS involvement (one in the 12 Gy, and five in the 18 Gy group).
  
  
  CONCLUSIONS
  Results demonstrate no disadvantage for patients irradiated with a reduced CNS dose of 12 Gy.
authors.affiliation: Pediatric Hematology/Oncology, University Hospital Muenster, Muenster, Germany. ursula@creutzig.de
authors.forename: Ursula
authors.initials: U
authors.lastname: Creutzig
authors.forename: Martin
authors.initials: M
authors.lastname: Zimmermann
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Bourquin
authors.forename: Michael N
authors.initials: MN
authors.lastname: Dworzak
authors.forename: Gudrun
authors.initials: G
authors.lastname: Fleischhack
authors.forename: Christine
authors.initials: C
authors.lastname: von Neuhoff
authors.forename: Annette
authors.initials: A
authors.lastname: Sander
authors.forename: André
authors.initials: A
authors.lastname: Schrauder
authors.forename: Arend
authors.initials: A
authors.lastname: von Stackelberg
authors.forename: Joerg
authors.initials: J
authors.lastname: Ritter
authors.forename: Jan
authors.initials: J
authors.lastname: Starý
authors.forename: Dirk
authors.initials: D
authors.lastname: Reinhardt
mesh_terms: D000293:Adolescent; D016543:Central Nervous System Neoplasms / Q000175:diagnosis / Q000517:prevention & control* / Q000532:radiotherapy* / Q000556:secondary; D002648:Child; D005260:Female; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000150:complications / Q000175:diagnosis / Q000532:radiotherapy*; D008297:Male; D012008:Recurrence