Acute Myelogenous Leukemia and Stem Cell Transplant
Marrow or blood cell transplants can treat acute myelogenous leukemia (AML) by transplanting healthy blood-producing cells into the patient's marrow. The three sources of blood-forming cells now being used for transplants are bone marrow, circulating blood (also known as peripheral blood) and umbilical cord blood.
The cells used for transplant can be the patient's own healthy cells (autologous transplant), or they can be collected from a compatible donor (allogeneic transplant). SCT is used more frequently than bone marrow transplant because of shortened recovery times and possible decreased risk of infection.
Click here to see frequently asked questions about blood and marrow.
Autologous Transplant
Cells are collected from the donor and usually frozen.
After the patient has received high-dose chemotherapy and/or radiation therapy, the cells are put back into the patient. Autologous transplant patients avoid graft-versus-host disease, which can be a serious side effect of an allogeneic transplant.
Allogeneic Transplant
Allogeneic transplants are more common because relapse is more common after autologous transplants.
The cells from allogeneic donors are rarely frozen; instead, they are usually infused into the patient within 24 hours of being collected
Allogeneic transplant require a donor that is either related (usually a sibling) or unrelated to the patient.
Patient thinking about an allogeneic transplant, the first thing a doctor does is to tissue type (glossary)the patient's family. If no matching family member is found, the patient's doctor can search the National Marrow Donor Program's Registry of more than 5 million potential donors or cord blood units for a match.
Graft-versus-host disease
Some allogeneic transplant recipients may get graft-versus-host disease (GVHD). In GVHD, the patient's new immune system -- created by the cells from the donor -- attacks the patient's body.
There are two types of GVHD: acute, when symptoms appear soon after transplant, and chronic, when symptoms develop slowly and may linger for months or years. Although GVHD can be very serious, doctors watch transplant recipients closely for signs of GVHD and can usually control GVHD with drugs.
Stem Cell Transplantation Facts
SCT allows the use of very high doses of chemotherapy while preserving the blood-producing stem cells.
The type of stem cell transplantation and the timing are determined after comprehensive analysis of
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the subtype of AML
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patient age and performance status
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cytogenetics
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availability of appropriate stem cells
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as well as other factors.
Usually around 14-21 days after the graft infusion, the stem cells begin making white blood counts (WBCs), platelets, and red blood counts (RBCs).
Stem Cell Transplantation Risks
Patients with core-binding factor AML are unlikely to relapse with chemotherapy alone therefore the risk of SCT in first complete remission is difficult to justify.
In contrast, very young patients(e.g. < age 18) have such a low-risk of transplant-related mortality that an allogeneic SCT in first complete remission is very reasonable.
For the remaining (the majority of patients), the outcome is dictated more by the characteristics of the AML (e.g. the cytogenetics ) than by the treatment (SCT or not).
One new approach to SCT is called “mini allogeneic stem cell transplantation”. The doses of chemotherapy are significantly lower than with a standard allogeneic SCT, with reliance placed on the ability of the graft to kill AML cells (“graft-vs-leukemia”).
Mini SCT is feasible in patients who have been considered ill-suited for SCT because of age (60 years or older) or problems such as ongoing infection.
Click here for a list of clinical trials for stem cell transplantation nationwide.
Click here for a list of treatment centers.
Sources
* MediFocus Guide from Medifocus.com, Inc.
* National Marrow Donor Program, www.marrow.org