Treatment of Newly Diagnosed Acute Lymphoblastic Leukemia in Children and Adolescents

Inclusion Criteria:

1. Confirmed diagnosis of acute lymphoblastic leukemia. Diagnosis should be made by bone marrow aspirate or biopsy demonstrating ≥ 25% involvement by lymphoblasts, with flow cytometry or immunohistochemistry confirming B-precursor or T-ALL phenotype.

   \-- For patients with circulating blasts in the peripheral blood, flow cytometry confirmation of B-ALL or T-ALL phenotype is sufficient for registration onto the study. Bone marrow aspirate and/or biopsy should be performed as soon as feasible, preferably prior to the initiation of any therapy.
2. Prior Therapy: No prior therapy is allowed except for the following:

   * Corticosteroids: Short courses of corticosteroid (defined as ≤ 7 days of corticosteroids within the 4-weeks preceding registration) are allowed prior to registration.

     \--- Participants who have been on corticosteroids chronically (defined as more than 7 days of corticosteroids within the 4-weeks preceding registration or more than 28 days of corticosteroids over the preceding 6 months) are not eligible.
   * IT cytarabine: A single dose of intrathecal cytarabine (at the time of the diagnostic lumbar puncture) is allowed prior to registration. If patient has received IT cytarabine prior to registration, Day 1 IT cytarabine should not be administered.
   * Emergent Radiation Therapy: Emergent radiation to the mediastinum or other life-threatening masses is allowed prior to registration.
3. Age: 365 days to \< 22 years
4. Direct bilirubin \< 1.4 mg/dL (23.9 micromoles/L).
5. Ability of parent or guardian to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

1. Mature B-cell (Burkitt's) ALL (defined by the presence of surface immunoglobulin and/or the t(8;14)(q24;q32), t(8;22), or t(2;8) translocation and/or c-myc-gene rearrangement).
2. World Health Organization diagnostic criteria of mixed phenotype acute leukemia (MPAL) or leukemia of ambiguous lineage
3. Any chemotherapy or radiotherapy for previous malignancy are not eligible.
4. Treatment in past with any anti-neoplastic agent, including methotrexate, 6-mercaptopurine, 6-thioguanine, vincristine cyclophosphamide, cytarabine (except for IT cytarabine), or any anthracycline, for any reason (eg, rheumatologic or autoimmune condition).
5. Currently receiving any investigational agents.
6. Known HIV-positivity
7. Uncontrolled intercurrent illness including, but not limited to ongoing infection with vital sign instability (hypotension, respiratory insufficiency), life-threatening acute tumor lysis syndrome (eg, with renal failure), symptomatic congestive heart failure, cardiac arrhythmia, intracranial or other uncontrolled bleeding, or psychiatric illness/social situations that would limit compliance with study requirements.
8. Pregnant women are excluded from this study because many of the agents used on this protocol have potential for teratogenic and/or abortifacient effects. Because there is an unknown but potential risk of adverse events in nursing infants secondary to treatment of the mother with these chemotherapy agents, breastfeeding should be discontinued if the mother is enrolled.
9. History of a previous malignancy. Exception: Individuals with a previous malignancy treated with surgery only (no chemotherapy or radiotherapy) more than 5 years prior to registration may be enrolled.