title: Outcome for children treated for relapsed or refractory acute myelogenous leukemia (rAML): a Therapeutic Advances in Childhood Leukemia (TACL) Consortium study.
abstract: BACKGROUND
  Current event-free survival (EFS) rates for children with newly diagnosed acute myeloid leukemia (AML) approach 50-60%. We hypothesize that further improvements in survival are unlikely to be achieved with traditional approaches such as dose intensive chemotherapy or hematopoietic stem cell transplants, since these therapies have been rigorously explored in clinical trials. This report highlights efforts to assess the response rates and survival outcomes after first or greater relapse in children with AML.
  
  
  METHODS
  We performed a retrospective cohort review of pediatric patients with relapsed and refractory AML (rAML) previously treated at TACL institutions between the years of 1995 and 2004. Data regarding disease characteristics at diagnosis and relapse, treatment response, and survival was collected on 99 patients and 164 medullary relapses or treatment failures.
  
  
  RESULTS
  The complete response (CR) rate following the second therapeutic attempt was 56 +/- 5%. CR rates following a third treatment attempt was 25 +/- 8% while 17 +/- 7% achieved CR following the fourth through sixth treatments. The 5-year disease-free survival in patients achieving CR following a second therapeutic attempt was 43 +/- 7%. The 5-year EFS and overall survival (OS) rates for all patients receiving a second treatment attempt was 24 +/- 5% and 29 +/- 5%, respectively.
  
  
  CONCLUSIONS
  This CR rate following a second therapeutic attempt and OS rate in patients with rAML is consistent with the literature. There are limited published data of CR rates for subsequent relapses. Our data can serve as a historical benchmark to compare outcomes of future therapeutic trials in rAML against traditional chemotherapy regimens.
authors.affiliation: Therapeutic Advances in Childhood Leukemia Consortium, USC-CHLA Institute for Pediatric Clinical Research, Los Angeles, California, USA.
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Gorman
authors.forename: Lingyun
authors.initials: L
authors.lastname: Ji
authors.forename: Richard H
authors.initials: RH
authors.lastname: Ko
authors.forename: Phillip
authors.initials: P
authors.lastname: Barnette
authors.forename: Bruce
authors.initials: B
authors.lastname: Bostrom
authors.forename: Raymond
authors.initials: R
authors.lastname: Hutchinson
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Raetz
authors.forename: Nita L
authors.initials: NL
authors.lastname: Seibel
authors.forename: Clare J
authors.initials: CJ
authors.lastname: Twist
authors.forename: Elena
authors.initials: E
authors.lastname: Eckroth
authors.forename: Richard
authors.initials: R
authors.lastname: Sposto
authors.forename: Paul S
authors.initials: PS
authors.lastname: Gaynon
authors.forename: Mignon L
authors.initials: ML
authors.lastname: Loh
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy* / Q000401:mortality; D008297:Male; D011379:Prognosis; D012008:Recurrence; D012074:Remission Induction; D019233:Retreatment; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult