Inclusion Criteria

DISEASE CHARACTERISTICS:

- Undergoing allogeneic hematopoietic stem cell transplantation* from a major
histocompatability complex (MHC)-identical related donor for 1 of the following:

- Primary refractory acute myelogenous leukemia (AML) or acute lymphoblastic
leukemia (ALL)

- AML or ALL beyond first remission

- Therapy-related AML at any stage

- Philadelphia chromosome (bcr-abl)-positive p190-positive ALL at any stage

- Acute leukemia at any stage arising from myelodysplastic syndromes or
myeloproliferative disorders, including any of the following:

- Chronic myelomonocytic leukemia

- Chronic myelogenous leukemia

- Polycythemia vera

- Essential thrombocytosis

- Agnogenic myeloid metaplasia with myelofibrosis

- Refractory anemia with excess blasts

- Refractory anemia with excess blasts in transformation NOTE: *Patients must be
enrolled on study prior to undergoing transplantation

- Relapsed disease post-transplantation, as evidenced by 1 of the following criteria:

- Morphologic relapse, as defined by 1 or more of the following:

- Peripheral blasts in the absence of growth factor therapy

- Bone marrow blasts > 5% of nucleated cells

- Extramedullary chloroma or granulocytic sarcoma

- Flow cytometric relapse, as defined by the appearance of cells with abnormal
immunophenotype consistent with leukemia relapse in the peripheral blood or bone
marrow (detected before transplantation)

- Cytogenetic relapse, as defined by the appearance in 1 or more metaphases from
bone marrow or peripheral blood cells of either a non-constitutional cytogenetic
abnormality detected in at least 1 cytogenetic study performed before
transplantation OR a new abnormality known to be associated with leukemia

- Molecular relapse, as defined by 1 of the following:

- 1 or more positive polymerase chain reaction (PCR) assays for clonotypic
immunoglobulin heavy chain or T-cell receptor gene rearrangement in
patients transplanted for B- or T-cell ALL respectively

- 1 or more positive post-transplantation reverse transcription PCR assays
for p190 BCR-ABL mRNA fusion transcripts in patients transplanted for
Philadelphia chromosome-positive p190-positive ALL

- No grade III or IV acute graft-versus-host disease (GVHD)**

- No extensive chronic GVHD** NOTE: **At time of post-transplant relapse

PATIENT CHARACTERISTICS:

Age

- 14 and over (patients < 14 years of age may be eligible if they are deemed to be of
sufficient height and weight by the pediatric attending physician)

Performance status

- Karnofsky 60-100% (at time of post-transplant relapse)

Life expectancy

- Not specified

Hematopoietic

- Not specified

Hepatic

- Not specified

Renal

- Not specified

Other

- No preexisting major nonhematopoietic organ toxicity ≥ grade 3 (at time of
post-transplant relapse)

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- Not specified

Endocrine therapy

- Concurrent immunosuppressive steroid therapy for GVHD allowed provided both of the
following are true:

- Able to taper steroid dose to < 0.5 mg/kg/day

- No increase of > 1 grade in acute GVHD OR progression of chronic GVHD within 14
days after dose change

Radiotherapy

- Not specified

Surgery

- Not specified