Helical Tomotherapy, Fludarabine Phosphate, and Melphalan Followed By Allo-HSCT in Hematological Malignancies

Inclusion Criteria: * Recipient, or recipient's parents, or recipient's legal guardians must have signed a voluntary, informed consent in accordance with institutional and federal guidelines * Must have histopathologically confirmed diagnosis in one of the followed categories: * AML * MDS with intermediate or high-risk disease * ALL * Children and adults at any age with significant morbidity, as determined by the primary bone marrow transplant (BMT) doctor (MD), and approved by the principal investigator (PI) * Able to lie supine in a full body cast for approximately 30 minutes, the anticipated duration of each treatment session; for younger patients deep conscious sedation may be required * Performance status evaluated by Zubrod or Karnofsky (KPS) Performance Scales in patients \> 16 years or Lanksy Performance Scale in children =\< 16 years must have a score \>= 70% * Adequate cardiac function: cardiac ejection fraction \> 50% by multi gated acquisition scan (MUGA) scan and/or by echocardiogram * Adequate pulmonary function: adults (older than 16 years): diffusing capacity of carbon monoxide (DLCO) \> 50%; for young children in whom pulmonary function tests (PFT) are not applicable: assessment by a pediatrician or pulmonary consult * Adequate renal function as demonstrated by: creatinine clearance or glomerular filtration rate (GFR) \> 60 cc/min (24 hour urine collection) * Serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT)…