Allogeneic Stem Cell Transplantation
This type of treatment, in which stem cells obtained from a donor are given to the patient by IV infusion, is the best-known and only potentially curative option for patients with myelodysplastic syndromes.
In an allogeneic transplant, the stem cells are obtained from a donor whose cells are compatible with those of the patient, usually either a brother or sister, or an unrelated donor. The cells are then infused into the patient after he or she is given very strong doses of chemotherapy, either with or without radiation therapy. This is called the “conditioning regimen.” The conditioning regimen not only destroys the abnormal cells in the bone marrow, it also destroys normal, healthy cells. Additionally, it weakens the immune system so that the body does not kill the transplanted blood stem cells.
High-dose chemotherapy can cause very bad side effects, and not all patients can tolerate it. Since allogeneic stem cell transplantation is a high-risk procedure, this treatment is mainly considered for
- Patients younger than age 60
- Patients up to age 75 who are in otherwise good health
- Patients who are in either the IPSS intermediate –2 or the IPSS high-risk category, or who have therapy-related (secondary) MDS (see International Prognostic Scoring System)
- Patients who have a human leukocyte-associated antigen (HLA)-matched stem cell donor (sibling or unrelated match).
Allogeneic stem cell transplants may also be considered for select lower-risk MDS patients with severe cytopenia. Autologous transplantation, using the patient’s own stem cells, is used in some other diseases but is not used in MDS since the patient’s own stem cells are abnormal because of the disease.
Graft Versus Host Disease. A serious risk of allogeneic stem cell transplantation is graft versus host disease(GVHD), which develops if the donor's immune cells attack your normal tissue. GVHD's effects can range from minor to life threatening.
Reduced-Intensity Allogeneic Stem Cell Transplantation
Patients who can't tolerate allogeneic transplantation with high-intensity chemotherapy may be eligible for reduced-intensity stem cell transplantation (sometimes called nonmyeloablative transplant).
With this type of transplant, patients receive lower doses of chemotherapy drugs and/or radiation. They receive immunosuppressive drugs to prevent rejection of the graft (donated cells) so that the donor's immune cells can attack cancer cells. This attack is called the graft-versus-tumor (GVT) effect
Studies are researching the use of this type of transplant in older adults who have relapsed and/or who have refractory disease. Reduced-intensity stem cell transplantation is usually used for patients who are older than 55 years.
Related Links
- Stem Cell Transplantation
- Managing Side Effects
- Download or order The Leukemia & Lymphoma Society's free booklets