This study investigates a new type of radiation therapy called total marrow irradiation (TMI) for patients undergoing allogeneic hematopoietic stem cell transplantation (Allo-HSCT). It aims to find the most effective dose of TMI when used with a chemotherapy drug called fludarabine. This combination is used to prepare patients for the transplant.
Participants in this study will receive TMI instead of the traditional total body irradiation (TBI). The study will assess whether TMI can reduce side effects by delivering less radiation to vulnerable organs. Participants will not be compensated for their involvement.
- Who can participate: Patients with Acute Myeloid Leukemia (AML) or Acute Lymphocytic Leukemia (ALL) not in complete remission, or with Myelodysplasia, may participate. Exclusion criteria include active infections, HIV positivity, pregnancy, previous radiation therapy, or stem cell transplantation.
- Study details: Participants will receive total marrow irradiation (TMI) along with chemotherapy to prepare for stem cell transplantation. A placebo is not used in this study.

