| The two primary types of BMT are autologous and allogeneic. Both are preceded by high-dose chemotherapy and/or radiation, which destroy not only the cancerous cells in your body, but healthy cells as well. You will be in the hospital during this time, to ensure that you are not exposed to possible infection. Then, during the transplant procedure, you’ll receive healthy cells from the donor (either your own previously harvested cells or another person’s cells), which make their way to your bone marrow and start producing new blood cells. |
Related Health Info 
Bone Marrow Aspiration & Biopsy
Allogeneic Stem Cell Transplant
Autologous Stem Cell Transplant
|
Autologous
In an autologous transplant, you are both the donor and the recipient. Stem cells from either your bone marrow or circulating (peripheral) blood are collected and stored in a frozen state. Following chemotherapy and/or radiation, your thawed stem cells will be re-infused into your blood stream.
The advantage of an autologous transplant is that you receive your own stem cells and they won’t be rejected by your body as a foreign substance. On the other hand, a possible disadvantage is that some cancer cells may be harvested along with the stem cells and then put back into your body. In a process called “purging,” your doctor may treat the cells first with anticancer drugs or other therapies to reduce the number of cancerous cells that may be present.
Allogeneic
An allogeneic BMT uses another person as your stem cell donor. This person must be a close tissue match to you. In a Related Allogeneic transplant, the donor is a relative, usually your brother or sister. If the donor is unrelated, it is called a Matched Unrelated Allogeneic BMT. There is a national registry of more than five million potential donors in the National Marrow Donor Program that your doctor will consult as your case is evaluated.
An advantage of allogeneic stem cell transplant is that the donor stem cells are free of cancer and they produce their own immune cells, which may help destroy any cancer cells that remain after your high-dose therapy. However, in some cases the donor’s stem cells will create new immune cells that attack the recipient’s body, a condition known as graft versus host disease (GVHD). There is also a small risk of certain infections from the donor cells.
Reduced Intensity (Mini Transplant)
Also known as mini transplants, reduced intensity transplants use lower dosages of chemotherapy and/or radiation than those given to patients who undergo a standard stem cell transplant. The infusion of stem cells remains the same.
Reduced intensity transplants are usually recommended for older patients (above age 60), who can’t tolerate the toxicity of standard chemotherapy and/or radiation. This treatment may not work well for patients with a lot of disease present at the time of transplant.
Cord Stem Cell
In the last two decades, physicians have investigated the use of stem cells from newborn babies’ umbilical cords and placentas. The advantage of this procedure is that it provides a high concentration of hematologic stem cells that are still immature in their immune capabilities. This means that they haven’t been around long enough to develop reactions against foreign invaders and therefore there is less likelihood that the stem cells will react against the recipient’s cells.
The good news is that cord stem cells might be used even if they aren’t a perfect match, since there is less chance of rejection with these immune-immature cells. However, the downside is that one umbilical cord and placenta contain a small volume of stem cells – only enough to transplant a child or very small adult.
In efforts to extend this therapy to adults, physicians are now using stem cells harvested from two cords, rather than just one. UCSD is utilizing this new technique as part of a multicenter clinical trial to follow the results of this therapy.
Additional, innovative techniques
With continuing research and clinical trials, new therapies are in development. One that UCSD is investigating involves a procedure called haploid identical transplant. Haploid, which means half, refers to your donor. For example, each of your parents have passed on one set of chromosomes to you and, therefore, will be haplo-identical to you for transplantation antigens. A brother or sister may also be haplo-identifcal to you if you share one of the sets of chromosomes from your parents. And, your child will be haplo-identical to you.
Now, researchers and physicians have developed strategies – currently in clinical trials – to alter the immune responsiveness to these half-matches. Check with UCSD’s clinical trials office to see if one of these trials is available for you.