Multiple myeloma is a cancer affecting plasma cells, a type of white blood cell in the bone marrow. For eligible patients, autologous stem cell transplantation is a treatment that allows for more intensive therapy to improve outcomes. The procedure is a multistep process designed to help the body recover after receiving high-dose chemotherapy. It involves collecting a patient’s own stem cells, which are reinfused after the intensive treatment phase to replenish the bone marrow with healthy, blood-producing cells.
Understanding Autotransplantation for Multiple Myeloma
Autologous stem cell transplantation (ASCT) enables the administration of high-dose chemotherapy to eliminate more myeloma cells than standard doses can. The patient’s previously collected stem cells are then reinfused to rescue the bone marrow from this intense treatment. This procedure is not a cure for multiple myeloma, but a strategy to induce a deeper and more durable remission. By reducing the cancer cell population, the goal is to prolong the period before the disease progresses.
ASCT is a standard component of care for many eligible patients, following an initial round of induction therapy. The use of a patient’s own cells distinguishes this from an allogeneic transplant, which uses stem cells from a donor. An autologous transplant is the standard approach for multiple myeloma because it avoids the risk of graft-versus-host disease, a complication where donor immune cells attack the patient’s tissues.
Goals of Autotransplantation in Multiple Myeloma Treatment
The primary objective of autotransplantation is to decrease the number of cancerous plasma cells in the bone marrow, surpassing what can be accomplished with initial therapies alone. The procedure is designed to improve the depth of remission, with the intent of achieving a complete response (CR) or a very good partial response (VGPR).
Another aim is achieving minimal residual disease (MRD) negative status, where no cancer cells are detected with highly sensitive tests. This status is associated with better long-term outcomes and can translate into longer periods without disease recurrence. These goals contribute to prolonging both progression-free survival (PFS) and overall survival (OS). While autotransplantation has shown a clear benefit in extending PFS, its impact on OS is part of ongoing study. The procedure is often followed by maintenance therapy to help sustain the remission.
The Autotransplantation Procedure Steps
The autotransplantation process begins with a thorough eligibility assessment. This evaluation considers several factors to determine if a patient is fit enough to tolerate the intensive nature of the procedure. These factors include:
- A patient’s age and general health
- The function of major organs like the heart and kidneys
- How the myeloma has responded to initial treatments
The second step is stem cell mobilization and collection, a process known as apheresis. Patients receive injections of a growth factor drug, such as granulocyte-colony stimulating factor (G-CSF), to encourage stem cells to move from the bone marrow into the bloodstream. Once a sufficient number of stem cells are circulating, they are collected from the blood using an apheresis machine and are then cryopreserved until needed.
Following cell collection, the patient undergoes a conditioning regimen. This involves receiving high-dose chemotherapy, with melphalan being a common agent for multiple myeloma. This treatment is administered to eradicate remaining myeloma cells but also destroys healthy blood-forming cells in the bone marrow.
A day or two after conditioning is complete, the cryopreserved stem cells are thawed and reinfused into the patient’s bloodstream through an intravenous line. The infused stem cells then travel back to the bone marrow to begin the process of engraftment.
Engraftment is the final phase, where the transplanted stem cells settle in the bone marrow and start producing new blood cells, including white blood cells, red blood cells, and platelets. This recovery of blood counts is monitored through daily blood tests and takes about 10 to 16 days.
Post-Transplant Recovery and Monitoring
The immediate post-transplant period requires careful management within a hospital setting for about two to three weeks. During this time, patients are observed as their blood counts drop to very low levels from the conditioning chemotherapy. This phase carries a high risk of infection, and supportive care measures are actively employed.
Common acute side effects from the high-dose chemotherapy include nausea, fatigue, hair loss, and mucositis, which is inflammation of the digestive tract lining. To manage these effects, patients may receive anti-nausea medications, nutritional support, and pain relief. Prophylactic antibiotics are often given to prevent infections, and blood or platelet transfusions may be necessary.
Healthcare teams monitor for engraftment by tracking the recovery of blood cell counts daily. Once the absolute neutrophil count reaches a safe, sustained level and the patient can manage food, drink, and oral medications, they can be discharged. The recovery process continues at home and can take several months.
Upon returning home, patients have frequent follow-up appointments to monitor their recovery and myeloma status. These check-ups, initially weekly, become less frequent over time. Many patients begin maintenance therapy with medications like lenalidomide after they have recovered from the transplant to help prolong remission.
Outcomes and Long-Term Considerations
Outcomes following an autologous stem cell transplant can vary among individuals. A primary goal is to achieve a deep and lasting remission, and studies show that about 50-60% of patients may achieve this. The duration of remission is influenced by factors like the genetic features of the myeloma and the patient’s response to initial induction therapy.
While the procedure can lead to long periods of disease control, relapse is a possibility. The median overall survival for patients after a transplant is approximately five to ten years, though ongoing advancements continue to improve these statistics. For some patients with high-risk disease, a second autotransplant may be considered.
Long-term side effects can occur. Persistent fatigue is common and can last for several months after the procedure. There is also a small risk of developing secondary cancers, such as myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML), years after the transplant due to the high-dose chemotherapy.
The transplant can improve quality of life by controlling myeloma symptoms, but managing the long-term physical and emotional aspects of recovery requires ongoing attention. Lifelong follow-up care is necessary to monitor for potential late effects and disease recurrence, ensuring any changes are addressed promptly.