Different Therapies in Treating Infants With Newly Diagnosed Acute Leukemia

DISEASE CHARACTERISTICS:

Inclusion criteria:

• Diagnosis of acute lymphoblastic leukemia (ALL) or biphenotypic leukemia meeting the following criteria:

  • Based on European Group for the Classification of Acute Leukemia (EGIL) diagnostic criteria
  • Newly diagnosed disease

  • Verified by morphology and confirmed by cytochemistry and immunophenotyping

    • Trephine biopsy is recommended (unless diagnosis can be confirmed by peripheral blood examination) in the event that bone marrow aspiration results in a "dry tap"

• Must have MLL gene rearrangements documented by split-signal fluorescence in situ hybridization and meets 1 of the following risk criteria:

  • Low-risk disease, defined as all MLL germline cases

  • Medium-risk disease, defined by 1 of the following criteria:

    • MLL status unknown
    • MLL rearranged AND age > 6 months
    • MLL rearranged AND age < 6 months AND WBC < 300 x 10^9/L AND prednisone good response

  • High-risk disease, defined by MLL rearrangement AND meets the following criteria:

    • Age at diagnosis < 6 months (i.e., < 183 days)
    • WBC ≥ 300 x 10^9/L AND/OR prednisone poor response

• Minimum donor and stem cell requirements for high-risk patients undergoing stem cell transplantation:

  • Donor meeting 1 of the following criteria:

    • HLA-identical sibling
    • Very well-matched related or unrelated donor
    • Must be HLA compatible in 10/10 or 9/10 alleles by 4 digit/allele high-resolution molecular genotyping

  • Stem cell source

    • Bone marrow (preferred source) OR peripheral blood stem cells of filgrastim [G-CSF]-stimulated donors OR cord blood

      • Highly-matched unrelated umbilical cord blood (UCB) (> 7/8 matches identified by high-resolution typing) accepted if a sibling donor is not able to donate bone marrow AND UCB with a sufficient number of nucleated cells (NCs) (i.e., > 1.5 x 10^7/kg recipient body weight [BW]) is cryopreserved
  • Must have ≥ 3 x 10^8 NCs/kg BW OR 3 x 10^6/kg BW CD34-positive cells available for transplantation
• CNS or testicular leukemia at diagnosis allowed

Exclusion criteria:

• Mature B-ALL, defined by the immunophenotypical presence of surface immunoglobulins or t(8;14) and breakpoint as in B-ALL
• Presence of the t(9;22) (q34;q11) or bcr-abl fusion in the leukemic cells (if data are not known, patient still may be eligible)
• Relapsed ALL

PATIENT CHARACTERISTICS:

• See Disease Characteristics

PRIOR CONCURRENT THERAPY:

• More than 4 weeks since prior systemic corticosteroids

  • Corticosteroids by aerosol are allowed