Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically proven, newly diagnosed multiple myeloma Eligible
if pancytopenia related to multiple myeloma At least 50% plasma cells in the bone marrow
OR Splenomegaly OR Plasma cell leukemia No solitary extramedullary plasmacytoma or plasma
cell dyscrasia

PATIENT CHARACTERISTICS: Age: Not specified Performance status: ECOG 0-2 Life expectancy:
At least 3 months Hematopoietic: If less than 50% plasma cells in bone marrow: WBC at
least 2,500/mm3 OR Absolute neutrophil count at least 1,000/mm3 (greater than 500/mm3 if
platelet count at least 75,000/mm3) Platelet count greater than 45,000/mm3
(thrombocytopenia related to idiopathic thrombocytopenic purpura or vitamin B12 or folate
deficiency allowed) Hepatic: Bilirubin no greater than 2 times upper limit of normal (ULN)
ALT or AST less than 2 times ULN (if greater than one third of liver involved, then no
greater than 5 times ULN) No severe hepatic disease Renal: Creatinine no greater than 2.0
mg/dL Other: No severe infection requiring intravenous antibiotics Not pregnant or nursing
Fertile patients must use effective contraception No prior malignancy within 5 years
except for treated basal cell or squamous cell skin cancer, or carcinoma in situ of the
cervix No Type I hypersensitivity or anaphylactic reactions to murine proteins or to any
component of rituximab

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior bone marrow transplantation
Concurrent sargramostim (GM-CSF) allowed for severe, symptomatic neutropenia Chemotherapy:
At least 4 weeks since investigational drugs Endocrine therapy: Not specified
Radiotherapy: Not specified Surgery: Not specified Other: No concurrent use of
investigational drugs or devices Concurrent epoetin alfa allowed for anemia Plasmapheresis
allowed at study onset to treat renal failure