Treatments vary depending on the specific type of myeloma, and other factors such as the patient’s age, overall health and prior therapy.
Chemotherapy is considered first-line treatment for myeloma. Because myeloma is a cancer of the blood and bone marrow, surgery is not an option. Chemotherapy is known as a “systemic” treatment (delivered throughout the body). Powerful drugs are needed to destroy myeloma cells. These may be given by mouth, or intravenously through an IV or catheter.
Chemotherapy is usually given in cycles. Some drugs for myeloma are given daily, with each month considered a full cycle. Others are given intermittently over a three-week period. There is usually a rest period between cycles to allow the patient’s blood cell counts to recover.
Treatment for myeloma involves combinations of agents such as Revlimid, thalidomide, Doxil (a new form of doxorubicin encapsulated in long-circulating Stealth liposomes) and Velcade, traditional agents such as melphalan and prednesone are also used.
Stem Cell Transplantation
Hematopoietic cell transplantation (HCT) and peripheral blood stem cell transplantation (PBSCT) use stem cells (immature blood cells) as part of the treatment of a bone marrow disorder. Because myeloma is a bone marrow disorder, stem cell transplantation offers a way to attack the disease at its root.
Transplant procedures include intensive chemotherapy with or without radiation therapy, first to ablate (destroy) the cancer cells, followed by an infusion of healthy new cells.
Studies have shown that stem cell transplantation with high-dose chemotherapy increases response rate and survival in myeloma patients compared with traditionalchemotherapy alone.
Autologous Stem Cell Transplantation
In autologous (self) transplants, a patient’s own stem cells are collected and frozen ahead of time. Typically, stem cells are collected from peripheral blood. After the cells have been stored, intensive chemotherapy and/or radiation treatments are given to destroy any cancer cells remaining in the body. Then, the healthy stem cells are infused back into the patient.
As these new stem cells grow, they restore the body's own blood cells. This type of procedure is commonly used for patients with myeloma after a few months of “induction” (initial) chemotherapy.
In some situations, an allogeneic transplant strategy is preferred, especially if the autologous transplant fails to control the disease. Allogeneic transplants use stem cells from a matched donor. Sometimes, a sibling is an ideal donor but, in many cases, a matched unrelated donor with a similar genetic type as the patient will be used.
Researchers now understand that the new immune system carried within the transplanted donor stem cells may help fight the cancer. This is known as the “graft-versus-tumor” effect, and is important in transplants for myeloma.
Ways to reduce allogeneic transplant-related complications are being studied, including less intensive "non-myeloablative" strategies (“mini-HCT” or “mini transplant”). These have a reduced risk of side effects because the initial chemotherapy or radiation doses are much lower. The success of this kind of transplant depends in part on the graft-versus-tumor effect of the donor stem cells.
Radiation therapy uses high-energy X-rays or other types of radiation to kill cancer cells or keep them from growing. As part of a transplant regimen for myeloma, traditional external beam radiation was found to be inferior to chemotherapy alone due to the radiation’s toxicity. However, newer, less toxic radiation technologies may be more effective, and are being explored in clinical trials.
City of Hope was the first to use the helical TomoTherapy System in myeloma transplant treatments. This system combines radiation delivery with real-time imaging, allowing doctors to create a higher energy dose that targets bone marrow more precisely. The system reduces unwanted exposure of normal tissues and may reduce potential complications. In some cases, solitary plasmocytomas may be treated by radiation alone.