Fludarabine and Radiation Therapy in Treating Patients Who Are Undergoing Donor Stem Cell Transplant for Chronic Phase or Accelerated Phase Chronic Myelogenous Leukemia

DISEASE CHARACTERISTICS:

* Diagnosis of Philadelphia chromosome-positive (Ph+) chronic myelogenous leukemia, meeting 1 of the following criteria:

  * Chronic phase

    * Ph+ by cytogenetics or fluorescent in situ hybridization (FISH) assay
  * Accelerated phase, meeting any of the following criteria:

    * More than 10% but \< 30% myeloblasts and promyelocytes in marrow or peripheral blood
    * Any additional clonal cytogenetic abnormalities
    * Increasing splenomegaly
    * Extramedullary tumor
    * WBC, platelet count, or hematocrit perturbations not controlled by therapy with hydroxyurea, interferon, or imatinib mesylate
    * Persistent unexplained fever or bone pain
* Less than 5% blasts in the marrow at time of transplantation
* Not eligible for OR refused conventional myeloablative allogeneic stem cell transplantation
* Failed OR suboptimal response to prior imatinib mesylate, as defined by 1 of the following:

  * Absence of complete hematologic response after \> 3 months of treatment with imatinib mesylate
  * Absence of cytogenetic response, as defined by 1 of the following:

    * Absence of any cytogenetic response (\< 95% Ph+ or BCR/ABL+ cells by cytogenetic or FISH analysis, respectively) after 6 months of treatment with imatinib mesylate
    * Absence of major cytogenetic response (\< 35% Ph+ or BCR/ABL+ cells by cytogenetic or FISH analysis, respectively) after 1 year of treatment with imatinib mesylate
    * Absence of complete cytogenetic response (no Ph+ cells by cytogenetic analysis OR BCR/ABL+ cells within normal limits by FISH analysis) after 18 months of treatment with imatinib mesylate
  * Hematologic evidence of disease progression
  * Cytogenetic evidence of disease progression

    * Increase in Ph+ cells or BCR/ABL+ cells by \> 20% with at least 1 month between sequential testing
  * Molecular evidence of disease progression

    * More than 10-fold increase in BCR/ABL mRNA levels by quantitative polymerase chain reaction (Q-PCR) with at least 1 month between 2 sequential tests
  * Experienced adverse events during treatment with imatinib mesylate that precluded further administration of the drug
* No CNS disease refractory to intrathecal chemotherapy
* HLA identical related donor available

  * Phenotypically matched at HLA-A, -B, -C, DRQ1, and DBQ1
* No presence of circulating leukemic blasts by standard pathology

PATIENT CHARACTERISTICS:

Age

* Any age

Performance status

* Karnofsky 70-100% OR
* Lansky 70-100%

Life expectancy

* Not specified

Hematopoietic

* See Disease Characteristics

Hepatic

* No fulminant liver failure
* No cirrhosis of the liver with evidence of portal hypertension or bridging fibrosis
* No alcoholic hepatitis
* No esophageal varices
* No history of bleeding esophageal varices
* No hepatic encephalopathy
* No uncorrectable hepatic synthetic dysfunction evidenced by prolongation of PT
* No ascites related to portal hypertension
* No bacterial or fungal liver abscess
* No biliary obstruction
* No chronic viral hepatitis AND bilirubin \> 3 mg/dL
* No symptomatic biliary disease

Renal

* Renal failure allowed

Cardiovascular

* No symptomatic coronary artery disease
* Ejection fraction ≥ 35%
* No other cardiac failure requiring therapy
* No poorly controlled hypertension (blood pressure ≥ 150/90 mm Hg) on standard medication

Pulmonary

* DLCO ≥ 30%
* Total lung capacity ≥ 30%
* FEV\_1 ≥ 30%
* No requirement for continuous supplementary oxygen
* No fungal pneumonia with radiological progression after treatment with amphotericin or mold-active azoles for \> 1 month

Other

* Not pregnant or nursing
* Fertile patients must use effective barrier contraception during and for 12 months after completion of study treatment
* HIV negative
* No other disease that severely limits life expectancy
* No other active malignancy except localized nonmelanoma skin cancer
* No nonhematologic malignancy within the past 5 years that is currently in complete remission and has a \> 20% risk of disease recurrence except for nonmelanoma skin cancer
* No systemic uncontrolled infection
* No active bacterial or fungal infection unresponsive to medical therapy

PRIOR CONCURRENT THERAPY:

Biologic therapy

* See Disease Characteristics

Chemotherapy

* See Disease Characteristics

Endocrine therapy

* Not specified

Radiotherapy

* Not specified

Surgery

* Not specified

Other

* At least 48 hours since prior imatinib mesylate