Umbilical Cord Blood (UCB) Transplantation in Pediatric Patients With High Risk Leukemia and Myelodysplasia

Inclusion Criteria:

Patients must be up to 21 years of age

Patients cannot receive total body irradiation (TBI) because of:

Young age - < 2 years at diagnosis of leukemia resulting in an age < 4 years at transplantation (due to risk of severe growth retardation and brain damage).
Inability to tolerate TBI because of prior radiation or organ toxicity.
Refractory/multiply relapsed leukemia, for which a traditional TBI/cyclophosphamide regimen would unlikely lead to a successful outcome.
Patients must have a partially human leukocyte antigen (HLA)-matched UCB unit. Unit must be HLA-matched minimally at 4 of 6 HLA-A and B (at intermediate resolution by molecular typing) and DRB1 (at high resolution by molecular typing) loci with the patient. The unit must deliver a pre-cryopreserved nucleated cell dose of at least 2.5 x 10^7 per kilogram.

Acute myelogenous leukemia (AML) at the following stages:

High risk first complete remission (CR1), defined as:

Having preceding myelodysplasia (MDS)
High risk cytogenetics (High-risk cytogenetics: del (5q) -5, -7, abn (3q), t (6;9) complex karyotype (>= 5 abnormalities)
Requiring > 2 cycles chemotherapy to obtain CR;
Second or greater CR.
First relapse with < 25% blasts in bone marrow.
Patients with therapy-related AML whose prior malignancy has been in remission for at least 12 months.
Acute lymphocytic leukemia (ALL) at the following stages:

High risk first remission, defined as:

Ph+ ALL; or,
Myeloid/lymphoid leukemia (MLL) rearrangement with slow early response [defined as having M2 (5-25% blasts) or M3 (>25% blasts on bone marrow examination on Day 14 of induction therapy)]; or,
Hypodiploidy (< 44 chromosomes or DNA index < 0.81); or,
End of induction M3 bone marrow; or,
End of induction M2 with M2-3 at Day 42.

High risk second remission, defined as:

Bone marrow relapse < 36 months from induction; or,
T-lineage relapse at any time; or,
Very early isolated central nervous system (CNS) relapse (6 months from diagnosis); or,
Slow reinduction (M2-3 at Day 28) after relapse at any time.
Any third or subsequent CR.
Biphenotypic or undifferentiated leukemia in any CR or if in 1st relapse must have < 25% blasts in bone marrow (BM).
MDS at any stage.
Chronic myelogenous leukemia (CML) in chronic or accelerated phase.
All patients with evidence of CNS leukemia must be treated and be in CNS CR to be eligible for study.
Patients ≥ 16 years old must have a Karnofsky score ≥ 70% and patients < 16 years old must have a Lansky score ≥ 70%.
Signed informed consent.

Patients with adequate physical function as measured by:

Cardiac: Left ventricular ejection fraction at rest must be > 40%, or shortening fraction > 26%
Hepatic: Bilirubin ≤ 2.5 mg/dL; and alanine transaminase (ALT), aspartate transaminase (AST) and Alkaline Phosphatase ≤ 5 x upper limit of normal (ULN)
Renal: Serum creatinine within normal range for age, or if serum creatinine outside normal range for age, then renal function (creatinine clearance or GFR) > 70 mL/min/1.73 m2.
Pulmonary: Diffusing capacity of the lungs for carbon monoxide (DLCO), Forced expiratory volume in 1 second (FEV1), Forced vital capacity (FVC) (diffusion capacity) > 50% of predicted (corrected for hemoglobin); if unable to perform pulmonary function tests, then O2 saturation > 92% of room air.

Exclusion Criteria:

Pregnant (B-positive HCG) or breastfeeding.
Evidence of HIV infection or HIV positive serology.
Current uncontrolled bacterial, viral or fungal infection (currently taking medication and progression of clinical symptoms).
Autologous transplant < 6 months prior to enrollment.
Prior autologous transplant for the disease for which the UCB transplant will be performed.
Allogeneic hematopoietic stem cell transplant < 6 months prior to enrollment.
Active malignancy other than the one for which the UCB transplant is being performed within 12 months of enrollment
Active CNS leukemia.
Requirement of supplemental oxygen.
HLA-matched related donor able to donate.