From the UpToDate article on multiple myeloma:
In most people, chemotherapy partially controls multiple myeloma; rarely, chemotherapy leads to complete remission.
Also:
Transplantation, when successful, prolongs survival, leads to a remission, and, infrequently, cures multiple myeloma. However, transplantation has several limitations. The high-dose chemotherapy given before transplantation usually fails to kill all of the plasma cells, allowing the condition to relapse after transplantation. Such treatment also puts the patient at risk for serious infections and bleeding, which can be fatal.
UpToDate is used by 700,000+ physicians worldwide; it's not alternative medicine. Thus, if even mainstream medicine recognizes the relative ineffectiveness of chemo and transplantation for multiple myeloma, why do they do it?