Stem cell transplant after high-dose chemotherapy is the most common treatment for people when first diagnosed with multiple myeloma. The purpose of a stem cell transplant in multiple myeloma is to replace cancerous bone marrow cells with stem cells that will form healthy bone marrow. Stem cell transplants take place after the cancerous cells of the bone marrow have been destroyed with chemotherapy, radiation, or a combination of the two.
The majority of people with multiple myeloma receive an autologous stem cell transplant. In an autologous stem cell transplant, the stem cells are harvested from the person’s own body. Autologous transplants are preferable in most cases because they will not attack the body. The risk with autologous stem cell transplants is that the peripheral blood stem cells may be contaminated with myeloma cells, which may contribute to a later relapse. Autologous stem cell transplants cannot cure myeloma.
Less commonly, an allogeneic stem cell transplant may be considered. In an allogeneic transplant, stem cells are harvested from a donor who is usually a sibling or other close blood relative of the recipient. Allogeneic transplants can cure myeloma in some cases, but they carry a high risk of severe side effects and death.
In the past, cells for transplant were taken from bone marrow. For this reason, some people still refer to stem cell transplants as bone marrow transplants. However, blood is now the most common source for hematopoietic (blood cell producing) stem cells for transplant in cases of multiple myeloma. Stem cells sourced from the blood may be referred to as peripheral blood stem cells.
Eligibility criteria for stem cell transplants varies between countries and individual hospitals. In general, people may be considered ineligible for stem cell transplants if they are over 77 years of age, have cirrhosis of the liver, or have heart disease or another condition severe enough to limit their ability to perform self-care and participate in normal daily activities.
What does it involve?
Most people with multiple myeloma undergo a course of chemotherapy, radiation, or both prior to receiving a stem cell transplant.
Peripheral blood stem cells are harvested before chemotherapy or early in the cycle of chemotherapy, and before radiation. The cells are then stored frozen until they are needed for the autologous stem cell transplant.
Stem cell transplants may be administered early – as soon as 24 hours after chemotherapy is complete – or reserved for later use until a relapse occurs. Doctors may advise early or delayed stem cell transplant based on many factors. People with multiple myeloma that is considered high-risk based on genetic studies are usually encouraged to undergo early stem cell transplant. Those whose myeloma is considered lower-risk may receive early stem cell transplant or be advised to reserve transplant in case of a relapse. Some people with myeloma receive two separate autologous stem cell transplants – known as double or tandem transplants – six to 12 months apart. Studies indicate that tandem transplants can provide greater benefits to some people with myeloma but may also cause more intense side effects.
The process of receiving a stem cell transplant is similar to receiving a blood transfusion. Stem cell transplants for multiple myeloma may be administered on an outpatient or inpatient basis. Between 30 and 40 percent of people with myeloma undergo outpatient stem cell transplants, undergoing daily monitoring for side effects. The majority of people will be admitted to the hospital during the stem cell transplant process. Those admitted to the hospital for stem cell transplant can expect to stay two to three weeks during recovery.
During the first weeks of recovery from stem cell transplant, people with myeloma may receive antibiotics and antiviral or antifungal medications to help protect them against infection. They may also require transfusions of red blood cells or platelets (cell fragments involved in the clotting process) to replace those destroyed by chemotherapy. Those who have undergone stem cell transplant for multiple myeloma are often given Erythropoietin (EPO), a hormone that encourages and speeds the growth of blood cells.
After receiving a stem cell transplant, people with multiple myeloma will receive two to three years of maintenance medications to sustain the treatment response.
Stem cell transplant can extend survival in people diagnosed with multiple myeloma.
In a study published in 2018 involving more than 13,000 people with multiple myeloma, median survival among participants who received autologous stem cell transplants was approximately 73 months. Those who did not receive stem cell transplants had a median survival of about 50 months. In other words, autologous stem cell transplants were shown to decrease the risk of death from multiple myeloma by nearly 20 percent.
In a study published in 2016, rates of relapse after autologous stem cell transplant for multiple myeloma were evaluated in 975 people. Researchers followed up with participants around 54 months after transplant. During that time, 273 (28 percent) of the participants experienced a myeloma relapse. The median time between transplant and relapse was 20 months.
Short-term side effects of stem cell transplant can include fatigue, headaches, fever and chills, nausea, vomiting, diarrhea, loss of appetite, weight loss, trouble sleeping, and skin rashes. Some people develop mucositis, inflammation of the digestive tract that can cause pain and make it difficult to eat. Some side effects, such as nausea, can be eased with other medications. Fatigue may be longer-lasting, persisting beyond the immediate recovery period. It may take months to fully recover after receiving a stem cell transplant.
In some people, myeloma fails to respond to stem cell transplant and begins to progress soon after the transplant.
For more details about this treatment, visit:
Stem Cell Transplant for Multiple Myeloma – American Cancer Society
Stem Cell Transplants – Multiple Myeloma Research Foundation
Stem Cell Transplant for Multiple Myeloma – Memoral Sloan Kettering Cancer Center
Stem cell transplants extend life for multiple myeloma patients – UC Davis Health
What are the Side Effects of a Stem Cell Transplant? – Dana-Farber Cancer Institute
Autologous hematopoietic cell transplantation in multiple myeloma – UpToDate
Patterns of Relapse Among Myeloma Patients Post-Autologous Stem Cell Transplant – Blood