Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed light-chain deposition disease based on the following
criteria:

- Deposition of granular material containing free light-chain (FLC)
immunoglobulins that did not bind Congo red

- Evidence of a plasma cell dyscrasia, as defined by any of the following:

- Monoclonal gammopathy in the serum or urine by immunofixation
electrophoresis

- Clonal plasmacytosis on bone marrow biopsy by IHC

- Elevated serum levels of FLC

- No overt multiple myeloma, as defined by any of the following:

- Greater than 30% bone marrow plasmacytosis

- Extensive (i.e., > 2) lytic lesions

- Hypercalcemia

- Patients may enroll after stem cell collection (SCC) if all prestudy requirements are
completed prior to starting SCC (i.e., ≥ 2.5 x 10^6 cells available for
transplantation)

PATIENT CHARACTERISTICS:

- Performance status 0-2

- LVEF ≥ 45% within the past 90 days

- No myocardial infarction, congestive heart failure, or arrhythmia refractory to
therapy within the past 6 months

- No prior malignancy except adequately treated basal cell or squamous cell skin
cancer, carcinoma in situ of the cervix, adequately treated stage I or II cancer from
which the patient is currently in complete response, or any other cancer from which
the patient has been disease-free for the past 5 years

- No HIV positivity

- DLCO ≥ 50%

PRIOR CONCURRENT THERAPY:

- Prior chemotherapy with alkylating agent allowed provided there is no evidence of
myelodysplastic syndromes

- Prior total dose of melphalan < 300 mg

- More than 4 weeks since prior cytotoxic therapy and recovered