Study of Blood and Tissue Samples in Children With Newly Diagnosed Acute Lymphoblastic Leukemia

DISEASE CHARACTERISTICS:

* Newly diagnosed acute lymphoblastic leukemia (ALL), meeting the following criteria:

  * FAB L1 or L2 morphology (any immunophenotype) and acute leukemias of ambiguous lineage (including biphenotypic or bilineal acute lymphoblastic leukemia)

    * Patients with mature B-cell acute lymphoblastic leukemia (B-ALL) (FAB L3 morphology and immunophenotypical mature B phenotype or B-ALL with documented presence of karyotype t(8;14), t(2;8) t(8;22) or breakpoints as in mature B-ALL) are excluded from this study
* Patients must also meet the following criteria for participating in individual translational research (TR) project:

  * TR 1 project (MRD prognostic significance in small ALL subgroups):

    * All patients, categorized according to response to pre-phase (\< or \> 1,000 peripheral blasts/mm³ at day 8) and minimal-residual disease (MRD) level at end of the induction therapy
    * iAmp(21q) detected at presentation
    * Hypodiploidy detected at presentation by karyotype and/or fluorescence in situ hybridization (FISH) and/or DNA index
  * TR 2 project (miRNAs expression in pediatric ALL):

    * Initially, average-risk 1 (AR1) patients
    * In a second stage, the analysis might be extended to low-risk patients that still show treatment failure and high-risk ALL patients
  * TR 3 project (Prognostic value of newly described mutations in childhood B-ALL)

    * Initially, only B-cell precursor ALL patients
  * TR 4 project (Pharmacogenetics of the response to prephase and induction therapy):

    * All ALL patients
  * TR 5 project (Clinical significance of genetic abnormalities in childhood T-ALL) :

    * All patients with T-cell ALL, as defined by expression of T-cell surface antigens
  * TR 6 project (RAS pathway activation in childhood B-ALL):

    * All patients with B-lineage ALL
* Patients with Philadelphia-chromosome positive ALL (documented presence of t(9;22)(q34;q11) and/or of the BCR/ABL fusion transcript) are eligible
* Scheduled to receive therapy as per institutional standard practice and have not started therapy (except for a maximum of 7 days of systemic corticosteroids prior to diagnosis)
* May only be registered to this study once

PATIENT CHARACTERISTICS:

* No psychological, familial, sociological, or geographical condition potentially hampering participation in the study protocol and follow-up schedule
* Patients with Down syndrome are eligible

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics