Bone marrow is the spongy tissue found in the center (medullary cavities) of bones that is responsible for producing red blood cells, white blood cells and platelets. As such, healthy bone marrow is essential to sustain life. Sometimes, diseases such as cancer can affect the bone marrow, preventing it from making these essential cells. In these instances, a bone marrow transplant may be necessary.
What are the types of bone marrow transplants?
There are three types of blood and bone marrow transplants – autologous, in which the stem cells are taken from the patient’s own blood; allogeneic, in which the stem cells are collected from a donor; or syngeneic, in which the stem cells are obtained from an identical twin.
Autologous stem cell transplants are commonly used to treat several kinds of blood cancer. In an autologous transplant, the donor is the patient himself or herself. The stem cells, which are harvested from the bone marrow and/or bloodstream, are typically collected from the patient when his or her disease is in remission, or at least in a more stable condition. Approximately one week before the transplant is to take place, the patient is given high-dose chemotherapy and sometimes radiation therapy to prepare his or her body for the transplant and destroy any lingering cancer cells (conditioning therapy). Finally, the stem cells are reintroduced to the patient via a central line.
Often recommended for patients with leukemia, allogeneic stem cell transplants involve collecting healthy stem cells from a donor who is a genetic match to the patient (often a sibling). This is similar to a syngeneic transplant, though the donor does not have to be an identical twin. Extensive DNA testing with any potential donor is required to ensure that the donor’s stem cells and white blood cells will be an appropriate match for the patient. With siblings, the chance is higher that the human leukocyte antigen (HLA) will match than with unrelated donors. However, if the transplant recipient does not have a sibling (or does not match with his or her siblings), stem cells from an unrelated donor may be utilized.
Sometimes, a patient and donor are not an identical match, but a transplant is still the best treatment option for the patient. To prepare for the transplant, the patient will first receive high doses of chemotherapy and radiation therapy. Then, the donor’s stem cells and white blood cells are infused through a vein, similar to a blood transfusion.
What does a bone marrow transplant treat?
Bone marrow transplants are a common form of treatment for patients with a number of different conditions. For instance, patients with the following conditions may benefit from a stem cell transplant:
- Leukemia (acute or chronic)
- Lymphoma (Hodgkin or non-Hodgkin)
- Multiple myeloma
- Multiple sclerosis
- Myelodysplastic syndromes
- Myeloproliferative neoplasms
- Paroxysmal nocturnal hemoglobinuria (PNH)
- Primary amyloidosis
- Severe anaplastic anemia (SAA)
- Testicular cancer
- Waldenstrom’s macroglobulinemia
- Essential thrombocytosis (ET)
- Ewing’s sarcoma
While a blood and bone marrow transplant is commonly used to treat individuals with these conditions, this procedure is not right for everyone. To determine if a transplant is the best option for any particular patient, the specifics of his or her case will be closely reviewed by the patient’s treatment team.
How do you prepare for a bone marrow transplant?
There are a number of steps that must be taken to prepare a patient for a bone marrow transplant. First, a series of tests must be administered to determine if the patient is healthy enough to undergo the transplant. A catheter (central line) may also be inserted into a vein in the chest, where it will remain for the duration of the transplant. After these initial procedures are completed, conditioning will begin. This involves receiving high doses of chemotherapy and possibly radiation therapy to destroy lingering cancer cells and suppress the immune system to prepare the body for the transplant. This process typically takes several days, though the dosage and duration of the conditioning therapies will depend on several factors unique to the patient. After conditioning has been completed, the patient is ready to receive the stem cell transplant.
Moffitt Cancer Center’s approach to a blood & bone marrow transplant
At Moffitt Cancer Center, we understand that a blood and bone marrow transplant is a complicated procedure that requires a great deal of commitment on the part of a patient and his or her caregiver. As a result, we’re here to provide comprehensive support to all of our transplant recipients, every step of the way.
To determine whether or not a patient is a good candidate for a bone marrow transplant, Moffitt’s transplant team will evaluate his or her age, individual care needs and medical history. During this process, we will also consider the various transplant techniques to determine which will be most beneficial to the patient.
If the patient requires an allogeneic transplant but does not have a sibling who is able to be the donor, Moffitt can search for a suitable volunteer donor through the National Marrow Donor Program. Currently, more than half of our allogeneic transplants are arranged with a volunteer donor, although an HLA match must still be obtained. Moffitt will also screen potential donors to ensure they are able to tolerate a stem cell harvest and that they do not have any active infections or other complications that might negatively impact their ability to donate.
When a patient is approved for a blood or bone marrow transplant procedure, Moffitt’s experienced physicians, nurses, lab technicians, transplant coordinators, dietitians and other medical professionals will work together to provide individualized guidance at every phase of the transplant process. This approach helps us achieve the most positive outcomes possible, while helping to enhance each patient’s quality of life.