Donor Stem Cell Transplant in Treating Patients With Hematologic Cancer or Other Diseases

Inclusion Criteria: * Histologically confirmed hematological disease, including any of the following: * Chronic lymphocytic leukemia * Absolute lymphocytosis \> 5,000/µL * Morphologically mature lymphocytes with \< 55% prolymphocytes * Lymphocyte phenotype with expression of CD19 and CD5 * Absence of CD23 expression allowed provided disease is morphologically distinguished from mantle cell lymphoma * Prolymphocytic leukemia * Absolute lymphocytosis \> 5,000/µL * Morphologically mature lymphocytes with \> 55% prolymphocytes * Non-Hodgkin's or Hodgkin's lymphoma * Any WHO classification histologic subtype * Diagnosis by core biopsy allowed provided there is adequate tissue for diagnosis and immunophenotyping * Diagnosis by bone marrow biopsy not acceptable for follicular lymphomas * Multiple myeloma * Has received ≥ 1 prior treatment regimen * Has a partial response or greater by the Blade Criteria * Patients who achieved complete remission are eligible * Acute myeloid leukemia * Documented control (i.e., \< 10% bone marrow blasts and no circulating blasts) * Myelodysplastic syndromes * Documented disease as defined by WHO or French-American-British Cooperative group criteria * Chronic myelogenous leukemia * Patients with atypical chronic myelogenous leukemia (i.e., absent Philadelphia chromosome) are eligible * Polycythemia vera * Documented disease as defined by WHO criteria (i.e., A1 + A…