2011
Maria Corriveau
Final Paper
12/5/2011
2011
Maria Corriveau
Final Paper
12/5/2011

Autologous peripheral blood stem cell transplantation for acute myeloid leukemia: an innovate technique
Autologous peripheral blood stem cell transplantation for acute myeloid leukemia: an innovate technique

Autologous peripheral blood stem cell transplantation for acute myeloid leukemia: an innovate technique

1. Principle of the technique
Bone marrow transplantation and peripheral blood stem cell transplantation are procedures that help to restore those stem cells that have been destroyed while going through radiation and/or chemotherapy. There are different types of transplantation: autologous, syngeneic, and allogeneic. Autologous transplantation is defined as the transplantation of owns stem cells. Syngeneic transplantation is when patients received stem cells from an identical twin. Lastly, allogeneic transplantation is when patients received stem cells from a sibling, or a parent, or other individuals not related to the patient as long compatibility is present.
Autologous bone marrow transplantation is a technique that was developed for patients with acute myeloid leukemia (AML) as an alternative to allogeneic stem cell transplantation. However, this technique was not very successful. Autologous bone marrow transplantation has been associated with prolonged marrow aplasia resulting in toxicity and mortality. After the failure of this technique, researchers found that they could use another method for transplantation: peripheral blood stem cell transplantation.
In this technique, hematopoietic growth factors offered the possibility of using peripheral blood instead of marrow for autologous transplantation. This technique offered the advantages of a faster engraftment and accelerated recovery compared to bone marrow stem cell transplantation. Peripheral Blood stem cell transplantation showed a more rapid returned of circulating cells that the ones observed in autologous bone marrow transplantation. 2. How it differs from current laboratory procedures
For over forty years, a classic method used for treatment to patient with acute myeloid leukemia was the extraction of hematopoietic stem cells from the bone marrow. This method was usually done by puncturing a bone (usually the hipbone) and drawing marrow with a syringe. Meanwhile, there is another method that is nowadays used: Peripheral blood cells transplantation. This method offers physicians the capability of harvesting cells from peripheral, circulating blood. This method is less invasive and painful.
During the last ten years, there has been research done, and it has been observed that researchers now can redirect marrow cells to circulating blood by injecting the donor with cytokine such as granulocyte-colony stimulating hormone. This allows physicians to insert a tube intravenously into donor’s vein allowing passage of blood through a filter, removing CD34 white blood cells, and returning red blood cells to the donor.
Nowadays, the majority of transplantations have been white blood cells extracted from peripheral circulation rather than bone marrow. This technique differs from bone marrow technique by the advantages it offers. This technique is easier, minimal pain is observed, no anesthesia is required, and no hospital stays. And the most important, it yields better cells for transplantation. 3. Clinical benefits for the patient
Hematopoietic stem cell transplantation offers patients to treat against the following conditions: 1. Patients undergoing autologous transplantation: * Multiple Myeloma * Non-Hodgkin lymphoma * Hodgkin disease * Acute Myeloid leukemia * Neuroblastomas * Autoimmune disorders * Germ cell tumors
For patients with acute myeloid leukemia, the treatment of choice is hematopoietic stem cell transplantation because is the only curative option for patients with primary refractory or relapse acute myeloid leukemia.
The benefits this technique provides to the donor and patient are: minimal to no pain, easier, no anesthesia necessary, and no hospital stay versus the anesthesia needed for bone puncture, and the need for hospital stay. Also, there is a less usage of antibiotics, and a lower transfusion requirement.
Other benefits observed when using peripheral blood stem cell transplantation are: earlier hematopoietic recovery and lower morbidity, greater cost-effectiveness when compared to bone marrow stem cell transplantation. A retro study conducted showed that peripheral blood stem cell transplantation was at least twenty-one percent less costly when compared to bone marrow transplantation. Also, this technique also aids in obtaining larger amounts of stem cells which offers a more viable option in the treatment for malignancies.
This technique not only offers curative benefits but it also offers less costly care.

4. Laboratory personnel considerations
Stem cell transplant laboratory personnel are responsible for processing, storage, and transplantation. When cells are collected, a sterile container must be used. Then cells are washed with a cold solution ((Medium-199), this solution contains heparin, donor plasma, and dimethyl sulfoxide). Then centrifugation is required. All steps must be done under very sterile conditions. After washed, cells are mixed gently in a blood bag and placed in an ice bag.
Other considerations that stem cell transplant laboratory personnel must be aware of when transfusing cells to a patient are: the side effects of the treatment, such as nausea, vomiting, diarrhea, fatigue, malaise, hair loss, and anorexia. 5. The future of this technique in hematology and laboratory practice.
There is a need for improvement while harvesting cells and growing cells. If improvement is met, then an increased safety while transplantation. This would help in better treatment for the patient. Also, once stem cell transplantation becomes a routine of treatment, researchers expect a decrease in contamination with tumor cells.
Also, researchers expect to have a decrease intensity of conditioning that would improve safety and increase applicability for allografts. Researchers hope to increase a higher cure rate.
Some of the probable future developments with this technique would be: 1. The growth of stem cells in the laboratory using cord blood that can be beneficial for adults with acute myeloid leukemia. 2. The need for improve techniques that would allow better autologous transplantation without the contamination of tumor cells due to this type of stem cell transplantation. 3. Increase used of donor not matched for HLA type. This is necessary when there is no relative donor. This would give more opportunities to survival. 4. Tumor specific vaccines to boots patient’s immune response to tumor cells 5. Less intensive chemotherapy. 6. Expansion of mini-transplantation using donor lymphocytes to clean up contamination with tumor cells. 7. Incorporation of new generation hematopoietic growth factors such as FLT3-ligand thrombopoietin. 8. Remission stabilization that would create much better condition and better leukemia control.