• Overall response rate (complete or partial) at 12 months [ Designated as safety issue: No ]
  

• Response [ Designated as safety issue: No ]
  
• Toxicity [ Designated as safety issue: Yes ]
  
• Time to progression (TTP) [ Designated as safety issue: No ]
  
• Time to best response [ Designated as safety issue: No ]
  

OBJECTIVES:

Primary

• To determine the response rate (overall and complete) after extended induction therapy comprising epratuzumab and rituximab in patients with previously untreated CD20+ follicular non-Hodgkin lymphoma (NHL).
• To determine the time to progression after extended induction therapy comprising epratuzumab and rituximab in patients with previously untreated CD20+ follicular NHL.

Secondary

• To determine the toxicity profile of epratuzumab and rituximab in patients with previously untreated CD20+ follicular NHL.
• To establish whether the therapeutic effects of the combination of epratuzumab and rituximab are sufficiently promising to warrant evaluation in a subsequent randomized trial (in comparison to rituximab alone).
• To determine the relationship between the change in fludeoxyglucose F 18 uptake early after epratuzumab and rituximab treatment with response rate and time to progression.

OUTLINE:

• Induction therapy (month 1): Patients receive epratuzumab IV over 5-30 minutes on days 1, 8, 15, and 22 and rituximab IV on days 3, 8, 15, and 22 in the absence of disease progression or unacceptable toxicity.
• Extended induction therapy (months 3, 5, 7, and 9): Patients receive epratuzumab IV over 5-30 minutes followed by rituximab IV in weeks 12, 20, 28, and 36 in the absence of disease progression or unacceptable toxicity.

Patients receive fludeoxyglucose F 18 (FDG) subcutaneously and undergo positron emission tomography at baseline and after induction therapy to assess the degree of FDG uptake.

After completion of study treatment, patients are followed every 4 months for 2 years then every 6 months for up to 10 years.

DISEASE CHARACTERISTICS:

• Histologically* confirmed follicular non-Hodgkin lymphoma (NHL)

  • Previously untreated disease
  • WHO classification grade 1, 2, or 3a (> 15 centroblasts per high power field with centrocytes present) that is stage III, IV, or bulky (i.e., single mass ≥ 7 cm in any unidimensional measurement) stage II disease NOTE: *Bone marrow biopsies as the sole means of diagnosis are not acceptable, but they may be submitted in conjunction with nodal biopsies; fine-needle aspirates are not acceptable for diagnosis
• Confirmed CD20 antigen expression by flow cytometry or immunohistochemistry

• Measurable disease by physical examination or imaging studies

  • Any tumor mass > 1 cm is acceptable

  • No nonmeasurable disease only, including any of the following:

    • Bone lesions
    • Ascites
    • Pleural/pericardial effusion
    • Lymphangitis cutis/pulmonis
    • Bone marrow (involvement by NHL should be noted)
• No known CNS involvement by lymphoma
• Required to participate in companion FDG-PET imaging study CALGB 580701

PATIENT CHARACTERISTICS:

• ECOG performance status ≤ 2
• Absolute neutrophil count ≥ 1,000/μL
• Platelet count ≥ 50,000/μL

• Patients with HIV infection are eligible provided they meet the following criteria:

  • No evidence of coinfection with hepatitis B or C
  • CD4+ cell count ≥ 400/mm^3
  • No evidence of resistant strains of HIV
  • If not on anti-HIV therapy, HIV viral load < 10,000 copies HIV RNA/mL
  • If on anti-HIV therapy, HIV viral load < 50 copies HIV RNA/mL
  • No history of AIDS-defining conditions
• Not pregnant or nursing
• Fertile patients must use effective contraception during and for 3 months after completion of study therapy
• No known Human Anti-Chimeric Antibody (HACA)-positivity

PRIOR CONCURRENT THERAPY:

• No prior therapy for NHL including chemotherapy, radiotherapy, or immunotherapy (e.g., monoclonal antibody-based therapy)
• More than 2 weeks since prior corticosteroids except for maintenance therapy for non-malignant disease

• No concurrent dexamethasone or other steroids as antiemetics except for the following circumstances:

  • Treatment of acute infusion reactions according to institutional procedures
• No concurrent hormonal therapy except steroids for adrenal failure OR hormones for non-disease-related conditions (e.g., insulin for diabetes)
• No other concurrent chemotherapeutic agents