• To optimize dosing of E. coli L-asparaginase during the intensification period [ Time Frame: 5 years ] [ Designated as safety issue: No ]
  
• To determine the side effects of prednisone versus dexamethasone. [ Time Frame: 5 years ] [ Designated as safety issue: Yes ]
  

• To compare randomized treatment groups using health-related, quality-of-life analysis [ Time Frame: 5 years ] [ Designated as safety issue: No ]
  

Drug: prednisone
Induction Phase: Given orally or intravenously Days 0-28 Intensification Phase: Given orally Days 1-5 of each cycle Continuation Phase: Given orally Days 1-5 of each cycle
Drug: dexamethasone
Intensification Phase: Given orally days 1-5 of each cycle Continuation Phase: Given orally days 1-5 pf each cycle
Drug: doxorubicin
Induction Phase: Intravenously on Days 0,1 Intensification Phase: Intravenously on Day 1 of each cycle
Drug: E. coli asparaginase
Intensification Phase: In the muscle weekly. Dose will vary
Drug: vincristine
Induction: Intravenously on days 0, 7, 14, 21 MLL Intensification Phase: Intravenously on Days 1, 8, 15, 22 CNS Therapy: Intravenously on Day 1 Intensification Phase: Intravenously on day 1 of each cycle Continuation Phase: Intravenously on Day 1 of each cycle
Drug: methotrexate
Induction: Intravenously on Day 2 MLL Intensification: Intravenously on Days 1, 8 Intensification: (when doxorubicin completed) Intravenously or into the muscle weekly Continuation: Intravenously or into the muscle weekly
Drug: Leucovorin
Induction Phase: Intravenously or orally begins 36 hours after methotrexate MLL Intensification: Intravenously or orally begins 36 hours after methotrexate
Drug: Asparaginase
Induction: Into the muscle on Day 4 MLL Intensification: Into the muscle on Days 16, 23
Drug: cytarabine
Induction: Intrathecal on Days 0, 14, 28 MLL Intensification: Intravenously on Days 15, 16, 22, 23
Drug: Methotrexate/Hydrocortisone
Induction: Intrathecal on Days 14, 28 MLL Intensification: Intrathecal on Days 2,9

• Children with acute lymphoblastic leukemia are treated somewhat differently depending on the relative risk of the leukemia recurring. Patients will be separated into "Standard Risk" and "High Risk".
• The treatment program for both groups is separated into 4 phases. The phases of treatment are induction, central nervous system (CNS) therapy, intensification and continuation.
• The induction phase of therapy lasts for about one month and its purpose is to kill all detectable leukemia cells. Patients in both groups will receive the following medication: prednisone, vincristine, doxorubicin, methotrexate, leucovorin, asparaginase, cytarabine (ARA-C), and hydrocortisone.

Patients in the "Hight Risk" group will also receive dexrazoxane.

• Patients whose leukemia is found to have a specific genetic abnormality involving a gene on chromosome 11 (known as MLL gene) will have a MLL intensification phase which begins after complete remission and lasts about 1 month. The drugs involved in MLL intensification are: vincristine, methotrexate, leucovorin, hydrocortisone, cytarabine and L-asparaginase.
• CNS therapy begins immediately after the end of induction therapy, after remission is documented. This phase of treatment should last 3 weeks and includes a series of spinal taps with the instillation of anti-leukemia drugs. Four spinal taps will be performed over a two-week period. Both groups will receive vincristine, 6-mercaptopurine and methotrexate/cytarabine/hydrocortisone. Patients in the "High Risk" group will also receive doxorubicin with dexrazoxane.
• Radiation therapy will also be delivered to patients in the "High Risk" group during the CNS therapy phase. Radiation will be given in 8 daily treatments. The total dose of radiation used during this study is lower than what has been used in the past to help reduce side effects without increasing the risk of relapse.
• The intensification phase begins after the CNS therapy ends and lasts for 30 weeks. This phase is intended to further reduce the number of leukemia cells in the body and consists of cycles of chemotherapy repeated every three weeks with weekly shots of asparaginase. The drugs administered to both groups during this phase are: prednisone or dexamethasone, vincristine,6-mercaptopurine, methotrexate, E. coli asparaginase and cytarabine. Patients in the "High Risk" group will also receive doxorubicin and dexrazoxane.
• The continuation phase begins after the completion of the intensification phase and the goal is to eradicate all leukemia from the body. It consists of cycles of chemotherapy repeated every 3 weeks and is continued until the patient has been in remission for 2 years. The drugs administered during this phase are vincristine, prednisone or dexamethasone, 6-mercaptopurine, methotrexate and cytarabine.
• During this trial there are two randomizations, each is between the "standard" treatment and the "investigational" treatment.

One randomization involves the drug E. coli L-asparaginase and two ways of dosing this drug. One way is to give the same standard dose of the drug that has been administered for years. The other way is to start with a lower dose and measure the amount of the drug in the blood every 3 weeks adjusting the dose as necessary. The goal of doing this is to maintain adequate drug levels with lower doses in the hope the it may reduce some side effects of the drug.

• The second randomization involves the drugs prednisone and dexamethasone. Both drugs have been used in the past to help treat ALL but it is not known if there is a difference between the two drugs, especially in terms of side effects. Patients will be randomized to either receive dexamethasone or prednisone.
• Throughout the study blood tests, urine tests, spinal taps, and bone marrow tests will be performed to monitor the disease status, side effects from medications and other complications from therapy.
• Quality of life questionnaires will also be performed by the patient (if older than 8), parent and patient's clinician.