Chemotherapy and Peripheral Stem Cell Transplantation in Treating Patients With Multiple Myeloma

DISEASE CHARACTERISTICS: * Diagnosis of multiple myeloma meeting 1 of the following criteria: * Bone marrow plasmacytosis with at least 10% plasma cells * Sheets of plasma cells * Biopsy-proven plasmacytoma * Meets at least 1 of the following criteria: * Presence of myeloma (M)-protein in the serum * Presence of M-protein in the urine * Radiographic evidence of osteolytic lesions * Generalized osteoporosis allowed if at least 20% plasma cells in bone marrow * No non-secretory myeloma * Prior M-protein in serum or urine allowed provided patient is now in complete remission * Must be receiving conventional-dose chemotherapy as initial therapy or as salvage therapy * Must have HLA-A, -B, and -DR genotypically identical sibling donor PATIENT CHARACTERISTICS: Age: * 18 to 70 Performance status: * ECOG 0-2 Life expectancy: * Not specified Hematopoietic: * See Disease Characteristics Hepatic: * AST no greater than 3 times upper limit of normal * Bilirubin less than 2.0 mg/dL Renal: * Not specified Cardiovascular: * LVEF greater than 40% at rest if symptomatic cardiac disease is present Pulmonary: * DLCO greater than 50% of predicted (corrected for hemoglobin) if symptomatic pulmonary disease is present Other: * Not pregnant or nursing * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: * No prior autologous or allogeneic peripheral blood stem cell or bone marrow transplantation Chemotherapy: *…