RATIONALE: Monoclonal antibodies, such as alemtuzumab, can locate tumor cells and either kill them or deliver tumor-killing substances to them without harming normal cells.

PURPOSE: This phase II trial is studying how well alemtuzumab works in treating patients with Waldenstrom's macroglobulinemia.

OBJECTIVES:

• Determine the objective response in patients with Waldenstrom's macroglobulinemia treated with alemtuzumab.
• Determine the time to treatment failure in patients treated with this drug.
• Determine the toxicity of this drug in these patients.

OUTLINE: This is a multicenter study.

Patients receive alemtuzumab IV over 2 hours on days 1, 3, and 5 of weeks 1-6 (course 1) in the absence of disease progression or unacceptable toxicity. Patients with a complete response undergo observation. Patients with stable disease or a minor or partial response receive an additional course of alemtuzumab, administered as in course 1, on weeks 7-12.

Patients are followed every 6 months for 2 years.

PROJECTED ACCRUAL: A total of 13-27 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Diagnosis of Waldenstrom's macroglobulinemia (lymphoplasmacytic lymphoma)

  • Immunoglobulin (Ig) M, IgG, and IgA paraprotein
  • Measurable monoclonal paraprotein

• Failed at least 1 prior first-line therapy (alkylator agent, nucleoside analogue, or rituximab)

• CD52-positive tumor determined by either bone marrow immunohistochemistry or flow cytometry

PATIENT CHARACTERISTICS:

Age

• Over 18

Performance status

• ECOG 0-2

Life expectancy

• At least 6 months

Hematopoietic

• Absolute neutrophil count ≥ 500/mm^3
• Platelet count ≥ 25,000/mm^3

Hepatic

• SGOT ≤ 2.5 times upper limit of normal (ULN)
• Bilirubin ≤ 2.5 times ULN

Renal

• Creatinine ≤ 2.5 mg/dL (> 2.5 mg/dL allowed if due to disease)

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective double-method contraception during and for 6 months after study participation
• No serious comorbid disease
• No uncontrolled bacterial, fungal, or viral infection
• No other active malignancy

PRIOR CONCURRENT THERAPY:

Biologic therapy

• See Disease Characteristics
• No prior alemtuzumab
• More than 3 months since other prior monoclonal antibody therapy

Chemotherapy

• See Disease Characteristics
• More than 21 days since prior chemotherapy

Endocrine therapy

• More than 21 days since prior steroid therapy

Radiotherapy

• More than 21 days since prior radiotherapy

Surgery

• Not specified