Inclusion Criteria:

- Histologically confirmed and immunophenotypically (CD20)-positive lymphoma at
original diagnosis, progression, or relapse

- Refractory to conventional therapy

- First recurrent/refractory CD20-positive non-Hodgkin's lymphoma (NHL) allowed if
ineligible for or refused regimens with known curative potential (high-dose
chemotherapy plus bone marrow transplantation) (if available)

- Second or third progression and/or recurrence of NHL

- Second or third relapse/refractory CD20-positive Hodgkin's lymphoma

- CD20-positive, post-transplantation lymphoproliferative lymphoma that is
medically refractory (decreased immunosuppression) to rituximab and/or
chemotherapy

- Medically refractory, HIV-associated, CD20-positive NHL

- Recurrent/refractory CD20-positive lymphoblastic lymphoma

- Autologous peripheral blood stem cells (PBSC) collected, selected for a minimum of 2
x 10^6 CD34-positive cells per kg, and cryopreserved before study entry

- Meets one of the following criteria for bone marrow reserve:

- Good marrow reserve, defined by both of the following:

- No prior myeloablative stem cell transplantation (SCT)

- No prior extensive radiotherapy, defined by any of the following:

- Prior total body irradiation

- Prior radiotherapy dose of 3,600 cGy or more to cranio-spinal axis

- Prior radiotherapy to 50% or more of bone marrow

- Poor marrow reserve, defined by either or both of the following:

- Prior myeloablative SCT

- Prior extensive radiotherapy

- Performance status - Lansky 50-100% (age 10 and under)

- Performance status - Karnofsky 50-100% (age 11 to 21)

- At least 2 months

- Absolute neutrophil count ≥ 1,000/mm^3

- Platelet count ≥ 100,000/mm^3 for patients with poor marrow reserve (transfusion
independent)

- Platelet count ≥ 150,000 for patients with good marrow reserve (transfusion
independent)

- Hemoglobin ≥ 8.0 g/dL (transfusion allowed)

- Bilirubin ≤ 1.5 times upper limit of normal (ULN)

- ALT ≤ 5 times ULN

- Albumin ≥ 2 g/dL

- Creatinine normal

- Creatinine clearance or glomerular filtration rate ≥ 70 mL/min

- Shortening fraction ≥ 27% by echocardiogram

- Ejection fraction ≥ 50% by MUGA

- No dyspnea at rest

- No exercise intolerance

- Oxygen saturation (SpO_2) > 94% by pulse oximetry (if there is a clinical indication
for SpO_2 assessment)

- Not pregnant or nursing

- Negative pregnancy test

- No documented infection that is unresponsive to appropriate antibiotic, antiviral,
or antifungal therapy

- No grade 2 or greater CNS toxicity

- Seizure disorder allowed if well controlled and on anticonvulsants

- See Disease Characteristics

- Recovered from prior immunotherapy

- At least 1 week since prior antineoplastic biologic agents

- Prior SCT allowed if the following criteria are met:

- At least 60 days since prior SCT

- Full hematopoietic reconstitution post-SCT

- No evidence of active acute or chronic graft-versus-host disease if post- allogeneic
SCT

- No concurrent sargramostim (GM-CSF)

- See Disease Characteristics

- At least 3 weeks since prior myelosuppressive chemotherapy (4 weeks for nitrosourea)
and recovered

- See Disease Characteristics

- Recovered from prior radiotherapy

- No concurrent medications that would interact with the study drug