Comparison of Two Salvage Chemotherapy Regimens Before Autologous Stem Cell Transplantation With or Without Maintenance Rituximab in Treating Patients With Relapsed or Refractory Aggressive Non-Hodgkin's Lymphoma

OBJECTIVES:

Salvage therapy

Primary

- Compare the response rate and transplantation rate in patients with relapsed or
refractory aggressive non-Hodgkin's lymphoma when treated with salvage chemotherapy
comprising dexamethasone, cisplatin, and gemcitabine with or without rituximab vs a
standard platinum-based regimen (dexamethasone, cisplatin, and high-dose cytarabine with
or without rituximab).

- To compare the transplantation rates of the two protocol salvage regimens.

Secondary

- Compare the event-free and overall survival of patients treated with these regimens.

- Compare the success rate of these regimens, in terms of getting patients to autologous
stem cell transplantation and successful mobilization after high-dose chemotherapy.

- Compare the quality of life of patients treated with these salvage regimens.

- Compare the toxic effects of these salvage regimens in these patients.

- Compare resource utilization for patients treated with these salvage regimens.

- Compare relative medical and societal costs of these salvage regimens with outcomes in
these patients.

Maintenance therapy

Primary

- Compare the 2-year event-free survival of patients with CD20+ B-cell lymphoma treated
with maintenance rituximab after these salvage regimens and autologous stem cell
transplantation to those patients who received no further treatment.

Secondary

- Compare the 2-year survival of patients treated with or without maintenance rituximab.

- Compare the toxic effects of rituximab vs observation alone in these patients.

OUTLINE: This is a randomized, multicenter study. For salvage therapy, patients are
stratified according to participating center, International Prognostic Index score at
relapse/study entry (0 or 1 vs 2 vs ≥ 3), immunophenotype (B cell vs T cell), response to or
response duration after initial chemotherapy (no response or progressive disease vs > 1 year
vs ≤ 1 year), and prior rituximab (yes vs no). For maintenance therapy, patients are
stratified according to participating center, salvage therapy treatment randomization (with
or without rituximab, cisplatin, dexamethasone, and gemcitabine vs with or without rituximab,
cisplatin, dexamethasone, and cytarabine), response to salvage therapy (complete response
[CR] and CR unconfirmed [CRu] vs partial response [PR] vs stable disease [SD]), and prior
rituximab (yes vs no).

- Salvage therapy: Patients are randomized to 1 of 2 treatment arms.

- Arm I: Patients receive cisplatin IV over 60 minutes on day 1, dexamethasone IV or
orally on days 1-4, and gemcitabine IV over 30 minutes on days 1 and 8. Patients
with CD20+ B cell lymphoma receive rituximab IV over 1.5-6 hours on day 1.

- Arm II: Patients receive cisplatin IV over 24 hours on day 1, dexamethasone as in
arm I, and cytarabine IV over 3 hours every 12 hours for a total of 2 doses on day
2. Patients with CD20+ B cell lymphoma receive rituximab IV over 1.5-6 hours on day
1.

In both arms, treatment repeats every 21 days for at least 2 courses in the absence of
disease progression or unacceptable toxicity.

Patients are reassessed after 2 courses. Patients with progressive disease are removed from
study. Patients with a CR, CRu, or PR proceed to autologous stem cell transplantation (ASCT).
Patients with SD may proceed to ASCT or receive 1 additional course of salvage therapy at the
discretion of the investigator. Patients receiving an additional course of salvage therapy
are then reassessed after the completion of therapy. Patients with progressive disease are
removed from study. Patients with a PR proceed to ASCT. Patients with SD may proceed to ASCT
or be followed off study at the discretion of the investigator.

- ASCT: Responding patients (or those with stable disease, if that is the center's
policy)undergo mobilization, stem cell harvest, and subsequent ASCT. Patients with CD20+
B-cell disease are randomized to maintenance therapy or observation.

- Maintenance therapy: Patients are randomized to 1 of 2 treatment arms.

- Arm I: Beginning on day 28 posttransplantation, patients receive rituximab IV once
every 2 months for 6 doses (a total of 12 months) in the absence of disease
progression or unacceptable toxicity.

- Arm II: Patients undergo observation only. Quality of life is assessed at baseline,
days 1 and 10 of course 2, day 1 of course 3 (if given), on the last day of salvage
therapy (or the first day of mobilization, if given), and at 1 month
posttransplantation.

Patients who undergo ASCT are followed at months 1, 3, 7, 13, 19, and 25 and then annually
thereafter. Patients who complete salvage therapy, but do not undergo ASCT are followed at
months 4, 8, 14, 20, and 26 and then annually thereafter. Patients who relapse or progress
are followed every 6 months until 25 months from ASCT or 26 months from completion of salvage
therapy and then annually thereafter.

PROJECTED ACCRUAL: A total of 637 patients will be accrued for this study within 3-4 years
for the first randomization, and 240 transplanted CD20+ patients will be needed for the
second randomization.

DISEASE CHARACTERISTICS:

- Histologically confirmed aggressive non-Hodgkin's lymphoma of 1 of the following
subtypes:

- Diffuse large cell lymphoma (includes primary mediastinal B-cell lymphoma and
T-cell-rich B-cell lymphoma)

- Prior indolent lymphoma (e.g., follicular center cell lymphoma; marginal zone
lymphoma, including extranodal mucosa-associated lymphoid tissue [MALT] lymphoma;
and lymphoplasmacytoid lymphoma) with transformation to diffuse large B-cell
lymphoma at relapse

- Must be histologically confirmed

- No transformed lymphoma at diagnosis with subsequent indolent histology
without transformation at relapse

- Peripheral T-cell lymphoma

- Anaplastic large cell lymphoma

- Small noncleaved Burkitt-like lymphoma

- T-cell or B-cell lineage confirmed by immunohistochemistry

- Clinically or radiologically documented disease meeting either of the following
criteria:

- Measurable disease, defined as at least 1 bidimensionally measurable site of
disease using clinical exam, CT scan, or MRI

- Lymph nodes must be > 1.5 cm by physical exam or CT scan

- Other non-nodal lesions must be ≥ 1.0 cm by physical exam, CT scan, or MRI

- Bone lesions are not considered measurable

- Evaluable disease, defined as only nonmeasurable disease, including any of the
following:

- Marrow infiltration

- Cytology-confirmed ascites or effusions

- Bony involvement

- Enlarged liver or spleen

- Unidimensionally measurable intrathoracic or abdominal masses

- Previously treated with 1, and only 1, chemotherapy regimen including an anthracycline
and excluding cisplatin, cytarabine, and gemcitabine

- No uncontrolled CNS involvement by lymphoma

- No CNS disease at time of relapse

- CNS disease diagnosed at initial presentation allowed provided a complete
response for CNS disease was achieved and maintained

PATIENT CHARACTERISTICS:

Age

- 16 to 65

Performance status

- ECOG 0-3

Life expectancy

- At least 12 weeks

Hematopoietic

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

- Platelet count ≥ 75,000/mm^3

Hepatic

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

- AST or ALT ≤ 2.5 times ULN (5 times ULN if liver involvement with lymphoma)

- Hepatitis B status known (for patients with a history of hepatitis B or who are at
high risk of hepatitis B infection)

Renal

- Creatinine ≤ 1.5 times ULN

Cardiovascular

- No significant cardiac dysfunction or cardiovascular disease

Other

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- Willing to complete quality of life questionnaires

- HIV negative

- No active, uncontrolled bacterial, fungal, or viral infection

- No other malignancy within the past 5 years except adequately treated basal cell skin
cancer or carcinoma in situ of the cervix

- No other concurrent serious illness or medical condition that would preclude study
participation

PRIOR CONCURRENT THERAPY:

Biologic therapy

- See Chemotherapy

- Prior rituximab allowed

Chemotherapy

- See Disease Characteristics

- At least 4 weeks since prior IV chemotherapy

- No prior high-dose chemotherapy with stem cell transplantation

Endocrine therapy

- No concurrent corticosteroids except for physiologic replacement

Radiotherapy

- At least 4 weeks since prior radiotherapy and recovered

- Exceptions may be made for low-dose, non-myelosuppressive radiotherapy

- No prior radiotherapy to more than 25% of functioning bone marrow

- Involved-field radiotherapy may be given to areas of bulky disease at relapse (≥ 5 cm)
after stem cell transplantation, according to the center's policy

Surgery

- At least 2 weeks since prior major surgery

Other

- No other concurrent anticancer therapy

- No other concurrent experimental agents