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Bone marrow transplant also known as stem cell transplant is a type of treatment for certain kinds of cancer. Bone marrow is a liquid tissue with a spongy-texture in the center of the bones. Its primary function is to produce blood cells that circulate in the body. Pelvic bone or hip bones have the highest number of bone marrow and stem cells. This is why most bone marrow transplantations are done by retrieving cells from the pelvic bone. The amount of bone marrow has to be sufficient to acquire a good number of healthy stem cells. Stem cells are white blood cells, red blood cells and platelets that are young or immature. Hematopoietic stem cells are young cells that have not been completely developed. Although these cells grow out to be the same, they can turn into any type of blood cell once matured. The type of cell it will mature into varies on the needs of the body when the cell is developing.
Stem cells are commonly found in the bone marrow. It is the place where they would divide themselves to produce new blood cells. After the blood cells have matured, they will leave the bone marrow and enter the bloodstream. When a few amount of immature stem cells enter the bloodstream, they are known as peripheral blood stem cells. Bone marrow transplantation is the infusion of healthy stem cells that are forming blood into the body to replace the bone marrow that have stopped the production of sufficient healthy blood cells.
The treatment is used to safely replace or recover the bone marrow that has been damaged from high dosage of chemotherapy or radiotherapy. It can also replace bone marrow that no longer functions properly with new stem cells. Bone marrow transplantation also provides new stem cells that can damage cancer cells.
Transplantation of stem cells are used to replace cells in the bone marrow that have been damaged by cancer or chemotherapy or radiotherapy that have been given to the patient for cancer treatment.
Bone marrow transplantation is often a choice for treatment in patients with cancer such as leukemia, lymphoma or multiple myeloma. The types of transplantations vary on the kind and severity of the disease.
The followings are the different types of bone marrow transplants:
- Autologous bone marrow transplant is when the patient is the donor. The stem cells will be collected by bone marrow harvest or apheresis which is a process of peripheral blood stem cells collection. The stem cells will be taken frozen, and infused back to the patient’s body after intensive treatment.
- Allogeneic bone marrow transplant is when the donor has the same type of genes as the patient. It could be from a brother or a sister. Other donors for this type of bone marrow transplants include:
- A parent. When the donor is the parent and is genetically matched or half identical to the recipient is called a haploid-identical match. This type of transplantation is rare.
- Unrelated bone marrow transplants (UBMT or MUD for matched unrelated donor) is genetically matched bone marrow with an unrelated donor.
- Umbilical cord blood transplant is when stem cells are collected from an umbilical cord after the birth of a baby. Those stem cells will mature into blood cells that would function faster and more effectively than stem cells taken from bone marrow of another child or adult. These stem cells are tested, counted, and freeze until they are required for transplantation.
To determine if bone marrow transplantation is a proper treatment option for the patient, consulting the doctor about the symptoms and potential health risks of each individual is an essential part of the treatment plan. As researchers are constantly discovering more data about bone marrow transplantation and other cancer treatments, recommendations may change.