- Myeloablative preparative regimen (i.e., >= TBI 12.0 Gy, >= busulfan (BU) 8.0 mg/kg PO, >= BU 6.4 mg/kg intravenously (IV), >= treosulfan 42 g/m^2 IV) according to investigational study or standard treatment plan; other "myeloablative" preparative regimens are acceptable as long as they are approved by the principal investigator or designee