Inclusion Criteria

DISEASE CHARACTERISTICS: Multiple myeloma confirmed by bone marrow plasmacytosis and with
measurable M-component in the serum or urine by immunoelectrophoresis or immunofixation No
Stage I myeloma No smoldering multiple myeloma Refractory to or in first relapse following
an initial response to VAD (vincristine/doxorubicin/dexamethasone), with relapse defined
as any of the following: 50% increase above the lowest remission level of serum or urine
M-protein while on therapy 25-50% increase above the lowest remission level of serum or
urine M-protein associated with either: Hypercalcemia (greater than 11 mg/dl) Hb decrease
of 2 g/dl attributable to increasing marrow plasmacytosis Appearance of new lytic lesions
Calcium no greater than 11 mg/dl No myeloma meningitis No plasma cell leukemia

PATIENT CHARACTERISTICS: Age: 18 to 65 Performance status: ECOG 0-2 Hematopoietic: WBC
greater than 500 (after G-CSF) Platelets greater than 25,000 Hepatic: Bilirubin no greater
than 2.0 mg/dl Renal: Creatinine no greater than 2.0 mg/dl Cardiovascular: No NYHA class
II-IV disease Pulmonary: DLCO at least 50% of predicted FVC at least 75% of predicted FEV1
at least 60% of predicted Other: No uncontrolled infection No active fungal infection No
fever No prior malignancy within 5 years except: Basal cell skin cancer In situ carcinoma
of the cervix No pregnant or nursing women

PRIOR CONCURRENT THERAPY: Biologic therapy: Prior biological response modifiers allowed
Chemotherapy: No time limit between cytotoxic therapy and protocol treatment Prior
cumulative melphalan dose less than 300 mg Endocrine therapy: Corticosteroids for
hypercalcemia allowed Radiotherapy: Prior radiotherapy allowed Prior pelvic radiotherapy
allowed, but patients with such therapy are unlikely to have adequate PBSC harvested
Surgery: Not specified