What is Bone Marrow Transplant ?
A special type of therapy for those patients who are suffering from certain diseases or cancers is known as bone marrow transplant (BMT). Bone marrow transplant, also known as hematopoietic stem cell transplant or stem cell transplant, includes taking of cells that can be found in the stem cells (bone marrow). These cells are filtered and are then given back to either other person or to the donor (patient). The aim of BMT (bone marrow transplant) is to transfer healthy bone marrow cells in a patient when their unhealthy bone marrow has been treated for destroying the abnormal cells. Following are the diseases that can be successfully treated by BMT that include –
- Some solid tumor cancers
- Multiple myeloma
- Severe aplastic anemia
- Immune deficiency disorders
Requirement of a Bone Marrow Transplant
A bone marrow transplant is required when high doses of radiation therapy or chemotherapy treatment has damaged the bone marrow stem cells. BMT may also be required when a disease has destroyed the bone marrow. A BMT is used for –
- Replacing of a bone marrow with a genetically healthy functioning bone marrow. This is done for preventing more damage from a genetic disease process such as adrenoleukodystrophy and Hurler’s syndrome.
- Replacing of non-functioning and diseased bone marrow with a healthy functioning bone marrow. This is done in specific conditions like sickle cell anemia, leukemia and aplastic anemia.
- Replacing the bone marrow for restoring its normal functioning after being given high-doses of radiation therapy and chemotherapy for treating a disease. This procedure is known by the name of rescue for conditions like neuroblastoma and lymphoma.
- Regenerating a new immune system that will help to fight off other cancers that are not destroyed by the radiation therapy or chemotherapy used in the transplant, or residual or existing leukemia.
Different Types of Bone Marrow Transplants
A number of bone marrow transplants are there that primarily depends on the donor that include –
- Allogeneic Bone Marrow Transplant : This implant requires a genetic type of the donor similar to the patient. The stem cells are then taken by apheresis or bone marrow harvest from a genetically-matched donor. This generally involves a sister or brother. Some of the other donors are-
- Unrelated Bone Marrow Transplants : An unrelated donor provides genetically matched stem cells or marrow. National bone marrow registries can provide these types of donor.
- A Parent : When the genetic match is minimally identical to the recipient and a parent is the donor then it is known as a haploid-identical match.
- Umbilical Cord Blood Transplant : Right away after the delivery of an infant, the stem cells are then taken from an umbilical cord. They then reproduce into functioning and mature blood cells that more effective as compared to those stem cells taken from the bone marrow of other adult or child.
- Autologous Bone Marrow Transplant : A patient is itself a donor. In this transplant, stem cells are taken from a patient by apheresis or bone marrow harvest. These cells are then given back to a patient after they have been frozen. Rescue is the name given to this process.
When do people need stem cell transplants?
A bone marrow transplant is required for certain reasons. A normal bone marrow transplant can be provided to those –
- Patients who are suffering from a genetic disease that may affect different body organs.
- Patients whose bone marrow has been damaged by radiation therapy and chemotherapy for treating cancer.
- Patients whose bone marrow stem cells are defective or abnormal.
- Patients who are relatively in good health in spite of their associated condition.
Bone Marrow Transplant Procedure
A bone marrow transplant depends on following conditions such as a patient’s ability to tolerate certain medications, the type of transplant and the disease that requires a transplant. The procedure includes the following –
- The preparation of a bone marrow transplant involves high doses of radiation therapy and/or chemotherapy. This is required for treating a specific disease and also to create a sufficient room in the bone marrow for the new cells to develop. Myeloablative or ablative is the name given to this therapy due to its effect on the bone marrow. Majority of blood cells in the body are produced by the bone marrow. The marrow becomes empty when the ablative or Myeloablative therapy stops the cell production. The new stem cells require an empty marrow so that they can grow and simultaneously establish themselves as new blood cell production system.
- The marrow transplant is given from the central venous catheter in the bloodstream after administering radiation therapy and/or chemotherapy. This process is not considered as a surgical procedure. The stem cells start to grow into healthy blood cells by making their way into the bone marrow.
- A supportive care is offered after the transplant for preventing complications, infections and side effects. This care involves providing a clean environment, frequent blood tests, and daily weigh-ins, strict measurement of fluid input and output, and monitoring of vital signs.