Myeloablative Hematopoietic Progenitor Cell Transplantation (HPCT) for Pediatric Malignancies

"Total Body Irradiation (TBI) 1200 cGy will be given on days -8,-7,-6 and -5 in eight sessions, delivering 150cGy in each session.~Etoposide 1000 mg/m2 as a 24 hour continuous infusion started on day -4.~Cyclophosphamide 60 mg/kg/day IV given over 1 hour daily on days -3, -2."

"Busulfan administration:~* For children \>/= 4 years of age, Busulfan 0.8 mg/kg/dose will be given every 6 hours over days -8,-7, -6, and -5 for a total of 16 doses.~* For children \< 4 years of age, Busulfan 1 mg/kg/dose will be given every 6 hours over days -8, -7, -6, -5 for a total of 16 doses.~* Pharmacokinetic analysis will guide dose modifications targeted to receive an average AUC of 800-1200 microMols\*min for the 16 doses.~Lorazepam (0.05 mg/kg) IV will be administered one half hour before the initial dose of Busulfan is given and every 6 hours through day -4.~Etoposide 1000 mg/m2 as a 24 hour continuous infusion started on day -4.~Cyclophosphamide 60 mg/kg/day IV given over 1 hour daily on days -3 and -2."

Hematopoietic progenitor cells (HPCs) will be infused on day 0. Source of cells may be bone marrow, peripheral blood cells, or cord blood units, from matched related or unrelated donors.

"Patients with prior CNS disease over the age of 1 year will be treated with 600 cGy of cranial irradiation in addition to 1200 cGy of TBI.~Patients diagnosed with ALL with CNS disease (at the time of diagnosis or relapse) \< 1 year of age will receive CNS treatment as Intrathecal Methotrexate as follows:~* Infants ≤ 1 year of age at the time of Intrathecal Therapy will receive a dosing of 7.5 mg once a month for 6 months after transplant beginning at day +30 with an adequate white count~* Children 1-2 years of age at the time of Intrathecal Therapy will receive 8 mg once a month for 6 months after transplant beginning at day +30 with an adequate white count"