An allogeneic stem cell transplant is a procedure in which a patient receives healthy stem cells from a donor. Either blood or bone marrow is collected from the donor and then passed through a machine that separates the stem cells. The patient then receives the stem cells through a central venous catheter (central line).
Why is allogeneic hematopoietic stem cell transplantation used?
An allogeneic bone marrow transplant may be used to treat types of lymphoma, leukemia, multiple myeloma and myelodysplastic syndrome, as well as other disorders. Conditions such as these affect the blood and/or bone marrow, so they can’t be treated by surgically removing a tumor, as may be the case with other cancers. Instead, systemic treatments (treatments that affect the whole body) like chemotherapy are typically the primary treatment.
When high doses of chemo (and sometimes radiation therapy) are used to destroy the cancer cells, it also destroys the healthy stem cells in the bone marrow. This is why an allogeneic bone marrow transplant would be used—to replace the stem cells that were lost. The donated stem cells find their way to the patient’s bone marrow, where they grow and develop healthy blood cells.
Allogeneic cell transplantation vs. autologous cell transplantation
There are two main types of stem cell transplants—allogeneic transplants and autologous transplants—and the difference between the two lies in who is donating the stem cells. As was noted above, during an allogeneic stem cell transplant, the patient receives stem cells from a donor. During an autologous stem cell transplant, the patient receives their own stem cells (the patient’s stem cells are removed and frozen before he or she undergoes chemotherapy and/or radiation therapy, and then thawed and returned once those other treatments are complete).
Each type of stem cell transplant offers its own set of risks and benefits. Although autologous transplants are less likely to be rejected by the patient’s body, there’s still a chance that the transplant will fail. There’s also a risk that cancer cells will be collected from the patient's body along with the stem cells, then returned to their body once the patient has already undergone chemotherapy and/or radiation therapy.
Conversely, while allogeneic stem cell transplants are more likely to get rejected or in rare cases cause an infection, they’re also more likely to help destroy any cancerous cells that are still present after chemotherapy and/or radiation therapy (commonly referred to as the graft-versus-cancer or graft-versus-tumor effect). Plus, if the patient requires additional stem cells, the donor may be able to make another donation.
What you can expect
At Moffitt Cancer Center, the multispecialty team within our Blood and Marrow Transplant and Cellular Immunotherapy Program collaborate to ensure each patient receives an individualized treatment plan that’s tailored to his or her needs. If an allogeneic transplant is recommended as part of your treatment, the first step involves finding a donor. An allogeneic stem cell transplant requires that someone donate marrow or blood stem cells for you. The donor may be:
- A close relative, such as a sibling or parent
- An anonymous volunteer donor from the National Marrow Donor Program ("Be The Match")
While an appropriate match is being found, you will receive conditioning to prepare for the transplant. Chemotherapy or immunotherapy may be used to help prepare your body to receive the healthy stem cells.
Patients undergoing an allogeneic transplant will be admitted to our specialized blood and bone marrow transplant inpatient unit to receive their preparative chemotherapy and transplant. Patients may remain in the hospital for several days to weeks and will be closely monitored by our medical team until it is safe for the patient to be discharged to an outpatient setting. Upon discharge, patients who have received an allogeneic bone marrow transplant are required to remain close to Moffitt for follow-up care, which is provided in our outpatient clinic and treatment center. Moffitt’s transplant program has several options for local lodging; you can discuss this with your assigned social worker.
What bone marrow donors can expect
While bone marrow is being collected, the donor will most likely be under general anesthesia. A provider will insert a hollow needle into the donation site (commonly the hip bone) to extract the marrow. Once the procedure is complete, the donor will likely continue to experience pain and tenderness at the donation site for about a week.
Allogeneic stem cell transplant precautions
The allogeneic stem cell transplant process begins by finding a matching donor. If you’ve been told that you need to undergo a transplant, you may have had friends and family members offer to donate their stem cells to you. While that is certainly a generous offer, it’s critical that a patient and their donor have closely matched human leukocyte antigens (HLA). In many cases, siblings who share both parents will be the best match. However, it’s also possible for another family member or even an unrelated volunteer to be a match.
If a patient and their donor are a close match, the patient will have less of a risk of developing graft-versus-host disease (GVHD). This condition occurs when the donor’s stem cells view the patient’s body as foreign, and as a result, begin attacking the patient’s organs and tissues as part of an immune response. There are two types of GVHD: acute and chronic. Some of the symptoms common to both types include:
- A skin rash
- Yellowing of the skin and/or eyes (jaundice)
- Loss of appetite
- Blood test results indicating abnormal liver function
GVHD is a serious condition that has the potential to become life-threatening. With that being said, this condition is generally treatable, often using immunosuppressive medication.
For more information on receiving an allogeneic stem cell transplant at Moffitt, call 1-888-663-3488 or complete a new patient registration form online. We stand apart from other cancer centers due to our remarkably fast response time—once you reach out, you can expect to be connected to a cancer expert within one day. This is faster than the turnaround times offered by every other cancer hospital in the country.