DISEASE CHARACTERISTICS:

• Diagnosis of intermediate or advanced multiple myeloma meeting criteria for at least 1 of the following:

  • Intermediate- to high-M-component production rates (immunoglobulin [Ig]G > 5 g/dL or IgA > 3 g/dL or urine M component > 4 g/24 hours)
  • More than one osteolytic bone lesion or radiographic evidence of diffuse osteoporosis
  • β-2 microglobulin > 3
  • Nonsecretory myeloma if bone marrow plasmacytosis is greater than 30%
• Must have undergone autologous peripheral blood stem cell transplantation within the past 3-4 months

PATIENT CHARACTERISTICS:

Age

• 18 to 69

Performance status

• Not specified

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,000/mm^3
• Platelet count ≥ 30,000/mm^3

Hepatic

• SGOT or SGPT ≤ 300 IU
• Bilirubin ≤ 2 mg/dL

Renal

• Creatinine ≤ 2.0 mg/dL OR
• Creatinine clearance ≥ 30 mL/min

Cardiovascular

• No concurrent major cardiac disease that would preclude study participation

Pulmonary

• No concurrent major pulmonary disease that would preclude study participation

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No peripheral neuropathy ≥ grade 2
• No history of hypersensitivity to bortezomib, boron, or mannitol
• No concurrent major gastrointestinal or bladder disease that would preclude study participation
• No concurrent major neurologic or psychiatric disease that would preclude study participation
• No dementia or significantly altered mental status that would preclude giving informed consent

PRIOR CONCURRENT THERAPY:

Biologic therapy

• See Disease Characteristics
• No prior interferon post-transplantation
• No prior thalidomide post-transplantation

Chemotherapy

• No prior chemotherapy post-transplantation

Endocrine therapy

• Not specified

Radiotherapy

• No prior radiotherapy post-transplantation

Surgery

• Not specified

Other

• No prior investigational therapy post-transplantation
• No prior bortezomib
• No prior therapy for myeloma post-transplantation
• No other concurrent anti-myeloma therapy
• No other concurrent investigational therapy