Treatment of Myeloma in Patients <= 65 Years Old With Response >= 50% After HSC Autotransplant by Allogenic Transplant Genoidentical or Phenoidentical After Reduced Intensity Conditioning

Donor mobilization : Donor will be mobilized with G-CSF (Granocyte) sub-cutaneous 10 µg/kg/day during 5 to 6 days. Hematopoïetic Stem Cell Harvest: By 1, 2, or 3 aphaeresis, a number of 4 x 106 cellules CD34+ /kg is required. If the CD34+ \>= 2 and \ 1/32. Transplant : HSC at D0 • 3 months after Transplantation : Disease Evaluation : * If CR : Supervision. Then if progression: 4 cycles of Bortezomib. * If no CR : Bortezomib (4 cycles) • Evaluation after Bortezomib cycles * If CR : Supervision. Then, if progression and no GvHD : DLI If no RC and no GVHD : DLI