title: Comparison of two schedules of intermediate-dose methotrexate and cytarabine consolidation therapy for childhood B-precursor cell acute lymphoblastic leukemia: a Pediatric Oncology Group study.
abstract: OBJECTIVE
  To compare efficacy and toxicity of two schedules of intermediate-dose methotrexate (IDM) and cytarabine (Ara-C) in remission consolidation of childhood acute lymphoblastic leukemia (ALL).
  
  
  METHODS
  In 1986, the Pediatric Oncology Group (POG) began a randomized trial to test two schedules of consolidation chemotherapy in children with newly diagnosed B-precursor cell ALL. MTX and Ara-C were given as overlapping 24-hour infusions. The dose and sequence of MTX and Ara-C administration were based on a preclinical model that had demonstrated synergism between these two agents. Two hundred fifteen patients in complete remission were randomized to front-loading consolidation therapy in which six MTX/Ara-C infusions were administered at 3-week intervals from the 7th through the 19th week of therapy. Two hundred thirteen patients in complete remission were randomized to receive standard consolidation therapy in which the six MTX/Ara-C infusions were given every 12 weeks from the 7th through the 67th week of therapy.
  
  
  RESULTS
  Both regimens produced similar rates of adverse side effects, except for a higher incidence of CNS toxicity in individuals randomized to the front-loading arm (32 of 215 v 12 of 213 patients, P = .002). Leukoencephalopathy occurred in three patients on the front-loading regimen and was permanent in one. By Kaplan-Meier analysis, the probability of continuing in complete remission for 5 years was 79% (SE = 5%) and 85% (SE = 5%) for good-risk patients, and 66% (SE = 6%) and 61% (SE = 7%) for poor-risk patients randomized to front-loading and standard regimens, respectively.
  
  
  CONCLUSIONS
  Although differences in complete remission durations were not statistically significant by log-rank analysis (P = .62 for good-risk patients, .89 for poor-risk patients, and .99 overall), the results are comparable to those in previous studies using more toxic agents as components of remission consolidation therapy.
authors.affiliation: St Louis Children's Hospital, Washington University Medical Center, MO.
authors.forename: V J
authors.initials: VJ
authors.lastname: Land
authors.forename: J J
authors.initials: JJ
authors.lastname: Shuster
authors.forename: W M
authors.initials: WM
authors.lastname: Crist
authors.forename: Y
authors.initials: Y
authors.lastname: Ravindranath
authors.forename: M B
authors.initials: MB
authors.lastname: Harris
authors.forename: R A
authors.initials: RA
authors.lastname: Krance
authors.forename: D
authors.initials: D
authors.lastname: Pinkel
authors.forename: D J
authors.initials: DJ
authors.lastname: Pullen
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000009:adverse effects; D002493:Central Nervous System Diseases / Q000139:chemically induced; D002648:Child; D002675:Child, Preschool; D003561:Cytarabine / Q000008:administration & dosage / Q000009:adverse effects; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage / Q000009:adverse effects; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D012074:Remission Induction; D012307:Risk Factors; D014481:United States
chemical_list: D003561:Cytarabine; D008727:Methotrexate