Chemotherapy, Total-Body Irradiation, Rituximab, and Donor Stem Cell Transplant in Treating Patients With B-Cell Non-Hodgkin's Lymphoma or Chronic Lymphocytic Leukemia

DISEASE CHARACTERISTICS:

- Diagnosis of 1 of the following:

- CD20-positive aggressive B-cell non-Hodgkin's lymphoma (NHL), including any of
the following subtypes:

- Diffuse large cell lymphoma*, meeting 1 of the following criteria:

- Relapsed disease after initial therapy, but failed to mobilize or had
bone marrow involvement and therefore is not suitable for an autologous
stem cell transplantation

- High-intermediate- or high-risk second-line, age-adjusted International
Prognostic Index score and in second complete remission (CR) or partial
remission (PR) after autologous stem cell transplantation

- Failed prior autologous stem cell transplantation and in PR or better
after salvage chemotherapy

- Large cell transformation of indolent NHL or chronic lymphocytic leukemia
(CLL), meeting the following criteria:

- In CR or PR of the large cell component of disease after salvage
chemotherapy or autologous stem cell transplantation

- Mantle cell lymphoma*, meeting 1 of the following criteria:

- High-risk disease (e.g., p53 positivity) and in first CR or PR after
initial therapy

- Relapsed disease after initial therapy and in second or third CR or PR
after salvage chemotherapy NOTE: *No progressive disease at allograft
work-up

- CD20-positive indolent NHL (e.g., follicular lymphoma, small cell lymphoma, or
marginal zone NHL) OR CLL

- Second or subsequent progression (pre-allograft cytoreduction necessary, but
CR or PR not required)

- Relapsed disease must be biopsy-proven

- Must have received pre-allograft salvage chemotherapy, including 1 of the following:

- Single autologous stem cell transplantation using high-dose chemotherapy
conditioning within the past 120 days

- At least 2 courses of intensive combination chemotherapy (e.g., RICE [rituximab,
ifosfamide, carboplatin, etoposide]), according to diagnosis, within the past 80
days

- CLL patients who have received CAMPATH do not have to receive pre-allograft
salvage chemotherapy

- HLA-compatible related or unrelated donor available

- HLA-matched ≥ 9/10 of the A, B, C, DRB1, and DQB1 loci, as tested by high
resolution typing

- One allele mismatch allowed

PATIENT CHARACTERISTICS:

- Karnofsky performance status 70-100%

- Creatinine < 1.2 mg/mL OR creatinine clearance ≥ 50 mL/min

- Bilirubin < 2.5 mg/dL

- AST and ALT ≤ 3 times upper limit of normal (unless benign congenital
hyperbilirubinemia is present)

- Spirometry and corrected DLCO ≥ 50% of normal

- LVEF ≥ 40%

- Albumin ≥ 2.5 g/dL

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No active uncontrolled infection, including active infection with Aspergillus or other
mold

- No HIV infection

- No hepatitis B antibody or antigen positivity

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior allogeneic transplantation