Myeloablative Allo HSCT With Related or Unrelated Donor for Heme Disorders

This is a Phase II study of allogeneic hematopoietic stem cell transplant (HCT) using a myeloablative preparative regimen (of either total body irradiation (TBI); or, fludarabine/busulfan for patients unable to receive further radiation). followed by a post-transplant graft-versus-host disease (GVHD) prophylaxis regimen of post-transplant cyclophosphamide (PTCy), tacrolimus (Tac), and mycophenolate mofetil (MMF).

-Inclusion Criteria: * Age: ≤ 60 years of age * Performance Status: Karnofsky ≥ 70%, Lansky play score ≥ 70 * Consent: Voluntary written consent (adult or legally authorized representative; or parental/guardian) * Adequate Organ Function: * Renal: Creatinine \95% on room air * Cardiac: Absence of decompensated congestive heart failure, or uncontrolled arrhythmia and left ventricular ejection fraction \> 45%. For children not able to cooperate with MUGA or echocardiography, such should be clearly stated in the physician's documentation * HIV Status: HIV infection with undetectable viral load. All HIV+ patients must be evaluated by Infectious Disease (ID) and a HIV management plan establish prior to transplantation Other Inclusion Criteria: * Women of child bearing potential and sexually active males with partners of child bearing potential must agree to use adequate birth control for the duration of treatment. * Donor Availability: Patients considered for transplantation must have a sufficient graft as based on current criteria of the University of Minnesota Blood and Marrow Transplantation Program * Eligible Diseases and Status: Patients are eligible unless their treatment is to be guided by a higher priority protocol. * Acute Leukemias: Must be in remission by morphology (≤5% blasts). Also a small percentage of blasts that is equivocal between marrow regeneration vs. early relapse are acceptable provided there are no associated cytogenetic markers consistent with relapse. * Acute Myeloid Leukemia (AML) and related precursor neoplasms: 2nd or greater complete remission (CR); first complete remission (CR1) in patients \> 60 years old; CR1 in ≤ 60 years old that is NOT considered as favorable-risk. * Favorable risk AML is defined as having one of the following: * t(8,21) without cKIT mutation * inv(16) or t(16;16) without cKIT mutation * Normal karyotype with mutated NPM1 and wild type FLT-ITD * Normal karyotype with double mutated CEBPA * Acute prolymphocytic leukemia (APL) in first molecular remission at the end of consolidation * Very high risk pediatric patients with AML: Patients \10% lymphoblasts in bone marrow on Day 14 of induction therapy) * Evidence of persistent immonophenotypic or molecular minimal residual disease (MRD) at the end of induction and consolidation therapy * Very high risk pediatric patients with ALL: patients \ CR/\> PR: Patients in CR/PR with initial short remission (\