Melphalan and Stem Cell Transplant Before Total-Body Irradiation and Donor Stem Cell Transplant in Treating Patients With Stage I-III Multiple Myeloma

Inclusion Criteria: * Meet Salmon and Durie criteria for initial diagnosis of multiple myeloma; transplant will be offered to patients with stage II or III multiple myeloma (MM) at diagnosis or have received chemotherapy and/or radiation therapy for progressive MM after initial diagnosis of stage I disease * The patient must have the capacity to give informed consent * Have received at least 4 cycles of conventional dose chemotherapy for MM * DONOR: HLA genotypically identical sibling * DONOR: Donor must consent to filgrastim (G-CSF) administration and leukapheresis for both peripheral blood stem cell (PBSC) allograft and subsequent DLI * DONOR: Donor must have adequate veins for leukapheresis or agree to placement of central venous catheter (femoral, subclavian) * DONOR: Age \< 75, older donors may be considered after consultation by Psychological Consultation Center (PCC) Exclusion Criteria: * Karnofsky score less than 60, unless due solely to myeloma * Left ventricular ejection fraction less than 40% * Bilirubin greater than 2 X the upper limit of normal * Serum glutamic pyruvic transaminase (SGPT) and serum glutamic oxaloacetic transaminase (SGOT) \> 2 X the upper limit of normal * Diffusion lung capacity of carbon monoxide (DLCO) \< 50% (corrected) or receiving continuous supplemental oxygen * Patients with poorly controlled hypertension * Pregnancy * Seropositive for the human immunodeficiency virus * Fertile men or women unwilling to use contraceptive techniques during and for 12 months following treatment * Creatinine clearance \< 40 cc/min at the time of initial autografting evaluation * Prior autograft (can be treated on alternative protocol) * DONOR: Identical twin * DONOR: Age less than 12 years * DONOR: Pregnancy * DONOR: Infection with human immunodeficiency virus (HIV) * DONOR: Inability to achieve adequate venous access * DONOR: Known allergy to G-CSF * DONOR: Current serious systemic illness * DONOR: Failure to meet Fred Hutchinson Cancer Research Center (FHCRC) criteria for stem cell donation as described in the standard practice guidelines of the institution