Autologous Hematopoietic Cell Transplantation, or Auto HCT, is a medical treatment using a patient’s own healthy blood-forming stem cells. These cells are collected and stored before the patient receives high-dose chemotherapy. After the intensive treatment is complete, the stored stem cells are returned to the patient’s body to help it recover its ability to produce blood cells.
Medical Conditions Treated with Auto HCT
Auto HCT serves as a rescue mission for the bone marrow. The goal of high-dose chemotherapy is to destroy cancer cells, but this powerful treatment also eliminates healthy stem cells in the bone marrow. The transplant itself does not directly fight the cancer; instead, it replenishes the bone marrow, allowing it to heal and resume producing blood cells.
This approach is most commonly used for specific types of blood cancers, including multiple myeloma and various forms of lymphoma. It may also be considered for certain solid tumors like germ cell tumors. The term “autologous” specifies that the stem cells are the patient’s own, which differs from an allogeneic transplant that uses cells from a donor. Using the patient’s own cells avoids complications like graft-versus-host disease.
The Auto HCT Procedure
The first step is preparing and collecting the stem cells. To increase the number of stem cells circulating in the bloodstream, patients receive injections of a growth-factor drug. This medication stimulates the bone marrow to overproduce stem cells and release them into the blood in a process called mobilization.
Once enough stem cells are circulating, they are collected through a procedure called apheresis. Similar to donating blood, this process involves drawing blood and passing it through a machine. The machine separates the hematopoietic stem cells, and the remaining blood is returned to the body. This collection may be repeated over a few days to gather enough cells, which are then cryopreserved, or frozen.
Following the collection and storage of the stem cells, the patient begins the conditioning regimen. This phase consists of receiving high-dose chemotherapy, sometimes combined with radiation therapy. The specific drugs and duration of the conditioning phase are determined by the type of cancer being treated and the patient’s overall health.
The final step is the stem cell infusion, often called “Day Zero” of the transplant. The previously collected and frozen stem cells are thawed and infused back into the patient’s bloodstream, much like a standard blood transfusion. These infused stem cells then travel through the bloodstream to the bone marrow, where they will begin rebuilding the blood supply.
The Engraftment and Recovery Period
After the stem cell infusion, the patient is closely monitored in the hospital while awaiting a process called engraftment. Engraftment is when the infused stem cells settle into the bone marrow and start to produce new blood cells, including red blood cells, platelets, and white blood cells. This phase takes about two to three weeks to begin.
Before engraftment is complete, the patient is particularly vulnerable. The high-dose chemotherapy depletes the body’s white blood cells, a condition known as neutropenia, which increases the risk of infection. Patients are monitored for signs of infection, and the hospital environment is controlled to minimize exposure.
Other side effects from the conditioning regimen are managed during this in-hospital stay. Mucositis, which causes painful sores in the mouth and throat, is a frequent issue that can affect eating and drinking. Nausea and significant fatigue are also expected as the body recovers. Medical teams provide supportive care to manage these symptoms until the new stem cells take hold.
Life After Transplant
Returning home after the transplant marks the beginning of a longer-term recovery phase. The immune system, which is severely weakened by the treatment, recovers slowly over a period that can last from several months to more than a year. During this time, patients remain at a higher risk for infections and are often advised to take precautions, such as avoiding large crowds and practicing diligent hand hygiene.
Follow-up care is a constant for the months and years following an auto HCT. Regular appointments with the medical team are necessary to monitor blood counts and ensure the bone marrow is functioning correctly. These visits also serve to watch for any signs of cancer recurrence, which remains a risk. The transplant is a method to allow for higher doses of chemotherapy, not a guarantee that all cancer cells have been eliminated.
Long-term management also involves monitoring for potential late effects of the treatment. The intensive chemotherapy can lead to issues that appear months or years later, such as chronic fatigue, thyroid problems, or an increased risk of developing secondary cancers. The follow-up care plan is designed to detect and manage these potential complications early.