Standard-of-Care Reduced-Intensity Conditioning (RIC) With 200 Versus 400 cGy of Total Body Irradiation (TBI) in Patients With Acute Leukemia Undergoing First Allogeneic Blood or Marrow Transplantation (BMT)

Inclusion criteria

• ✓. Age ≥ 0 years
• ✓. Patients with a diagnosis of acute myeloid leukemia (AML), acute lymphoblastic leukemia or lymphoma (ALL), or acute leukemia of mixed or ambiguous lineage per the 2022 World Health Organization classifications,75,76 with \< 5% blasts on bone marrow morphologic analysis performed within 30 days of planned conditioning initiation
• ✓. AML is generally defined as ≥ 20% myeloid blasts identified in the peripheral blood and/or bone marrow. Myeloid sarcoma is also recognized as an AML-defining entity. Situations in which AML can be diagnosed without a specific blast threshold met nor myeloid sarcoma present are when fusions involving RUNX1::RUNX1T1, CBFB::MYH11, DEK:NUP214, or RBM15::MRTFA are present; rearrangements involving KMT2A, MECOM, or NUP98 exist; or there is a mutation in NPM1.
• ✓. B- or T-ALL is defined as the presence of lymphoid blasts identified in the peripheral blood and/or bone marrow with no specific blast threshold needed (acute lymphoblastic leukemia) or the presence of a lymphatic-based collection of lymphoblasts (acute lymphoblastic lymphoma).
• ✓. Acute leukemia of mixed or ambiguous lineage is defined as mixed or ambiguous lineage blasts identified in the peripheral blood and/or bone marrow or the presence of a lymphatic-based collection (lymphoma) of mixed or ambiguous lineage blasts. A specific blast threshold does not need to be met.
• ✓. Patients with a documented diagnosis of myeloproliferative neoplasm (MPN), myelodysplastic syndrome or neoplasm (MDS), and/or MDS/MPN-overlap prior to diagnosis of acute leukemia may be included for randomization in this clinical trial so long as the patient has received at least 4 cycles of DNA methyltransferase inhibitor (e.g., azacitidine, decitabine, decitabine/cedazuradine (Inqovi), and/or any other agent that works via this mechanism) or at least one cycle of induction chemotherapy. A list of antecedent diagnoses per the World Health Organization 2022 classification of hematolymphoid tumors that pertain to this inclusion criterion are listed below 75