Targeted Marrow Irradiation, Fludarabine Phosphate, and Busulfan Before Donor Progenitor Cell Transplant in Treating Patients With Hematologic Malignancies

This phase I trial studies the side effects and best dose of targeted marrow irradiation when given with fludarabine phosphate and busulfan before donor progenitor cell transplant in treating patients with hematologic malignancies. Targeted marrow irradiation is a type of specialized radiation therapy that delivers a high dose of radiation directly to the cancer cells, which may kill more cancer cells and cause less damage to normal cells. Giving targeted marrow irradiation and chemotherapy drugs, such as fludarabine phosphate and busulfan, before a donor progenitor cell transplant may help stop the growth of cancer cells. It may also stop the patient's immune system from rejecting the donor's progenitor cells. When the healthy progenitor cells from a donor are infused into the patient they may help the patient's bone marrow make progenitor cells, red blood cells, white blood cells, and platelets.