Fludarabine Phosphate, Busulfan, Anti-thymocyte Globulin, and Total-Body Irradiation before Donor Stem Cell Transplant in Treating Younger Patients with Leukemia

Inclusion Criteria

• Acute myelogenous leukemia (AML) at the following stages: * High risk first complete remission (CR1), defined as: ** Having preceding myelodysplasia (MDS) ** High risk cytogenetics (high-risk cytogenetics: del (5q) –5, -7, abn (3q), t (6;9) complex karyotype (>= 5 abnormalities) with any minimal residual disease (MRD) status ** Requiring >= 2 cycles chemotherapy to obtain complete response (CR) ** High allelic ratio fms-related tyrosine kinase 3 (FLT3)/internal tandem duplications positive (ITD+) ** Standard risk cytogenetics with positive MRD at end of induction * Second or greater CR * First relapse with < 25% blasts in bone marrow
• Patients with therapy-related AML whose prior malignancy has been in remission for at least 12 months
• Acute lymphocytic leukemia (ALL) at the following stages: * High risk first remission, defined as: ** Philadelphia chromosome positive (Ph+) ALL; or ** Mixed lineage leukemia (MLL) rearrangement with slow early response [defined as having M2 (5-25% blasts) or M3 (> 25% blasts on bone marrow examination on day 14 of induction therapy); or ** Hypodiploidy (< 44 chromosomes or deoxyribonucleic acid [DNA] index < 0.81); or ** End of induction M3 bone marrow; or ** End of induction M2 marrow or MRD > 1% with M2-3 marrow or MRD > 1% at day 42 ** High-risk infant ALL defined as age < 6 months at diagnosis with MLL (11q23) translocation * High risk second remission, defined as: ** Bone marrow relapse < 36 months from induction; or > 36 months (mths) if a matched sibling donor is available ** T-lineage relapse at any time; or, ** Very early isolated central nervous system (CNS) relapse (< 18 months from diagnosis); or ** Slow reinduction (M2-3 at Day 28) after relapse at any time * Any third or subsequent CR
• Biphenotypic or undifferentiated leukemia in any CR or if in 1st relapse must have < 25% blasts in bone marrow (BM)
• MDS at any stage; prior therapies allowed
• Chronic myelogenous leukemia (CML) in chronic or accelerated phase; prior therapies allowed
• All patients with evidence of CNS leukemia must be treated and be in CNS CR to be eligible for study
• The donor and the patient and/or the patient’s legally authorized guardian must acknowledge in writing that consent to become a study subject has been obtained in accordance with the institutional policy approved by the United States (U.S.) Department of Health and Human Services
• Serum creatinine < 2x normal, or creatinine clearance (as determined by the Schwartz formula Cockcroft and Gault) > 40ml/min/m^2 or 70ml/min
• Total bilirubin =< 2x normal
• Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) =< 4x normal
• Shortening fraction > 24% by echocardiogram, or ejection fraction > 30% by radionuclide angiogram
• Diffusing capacity of the lungs for carbon monoxide (DLCO) > 60% by pulmonary function test
• Forced expiratory volume in 1 second (FEV1) > 60% by pulmonary function test
• Forced vital capacity (FVC) > 60% by pulmonary function test
• For children who are uncooperative for pulmonary function tests and have no evidence of dyspnea at rest or exercise intolerance, pulse oximetry > 94% on room air is considered acceptable, with a normal chest X-ray
• Adequate performance status; Lansky score >= 60% for children < 16 years of age, or Karnofsky score >= 60% for those > 16 years of age
• Venous access: a double lumen central vascular access device or its equivalent and an additional peripherally inserted central catheter (PICC) line will be required for all patients entered on protocol
• Women of childbearing potential and sexually active males should use effective contraception while on study

Exclusion Criteria

• Inability to give informed consent or assent
• Inability to obtain a suitable donor
• Patient who is human immunodeficiency virus (HIV)-positive
• Patient who has active Hepatitis B
• Patient who is pregnant
• Patient who is otherwise considered unsuitable for transplant at the discretion of the principal investigator