Donor Stem Cell Transplant After Conditioning Therapy in Treating Patients With Hematologic Cancer, Recurrent or Metastatic Solid Tumor, or Other Disease

DISEASE CHARACTERISTICS:

* Diagnosis of 1 of the following:

  * High-risk acute leukemia, including any of the following:

    * Refractory acute leukemia
    * Acute leukemia beyond first remission
    * Acute leukemia in first remission with poor prognostic features (e.g., chromosomal changes suggesting poor prognosis)
  * Chronic myelogenous leukemia in second chronic, accelerated, or blastic phase
  * Severe aplastic anemia that is not responsive to immunosuppressive therapy
  * Myelodysplastic syndromes, including any of the following:

    * Refractory anemia (RA) or RA with ringed sideroblasts with severe cytopenia
    * RA with excess blasts (RAEB)
    * RAEB in transformation
    * Chronic myelomonocytic leukemia
  * Refractory or relapsed non-Hodgkin or Hodgkin lymphoma
  * Multiple myeloma
  * Biopsy proven measurable solid tumor meeting 1 of the following criteria:

    * Recurrent disease after primary treatment and deemed incurable to standard treatment
    * Metastatic disease for which no known standard therapy that is potentially curative or definitely capable of extending life expectancy exists
* Must have a related HLA-haploidentical mismatched (3/6 or fewer loci) donor available

PATIENT CHARACTERISTICS:

* Karnofsky performance status 70-100%
* Bilirubin \< 2.0 mg/dL
* AST \< 3 times upper limit of normal
* Creatinine \< 2.0 mg/dL
* Ejection fraction \> 40% by MUGA

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics