Bone marrow is a soft and spongy material found in the center of long and large flat bones in the human body. It is composed of red and yellow bone marrow, which is packed with a vital cell called "stem cell," which produces haemoglobin, white blood cells, and platelets continuously throughout the life span.
Bone marrow transplantation (BMT) is a modality of treatment where the defective bone marrow is replaced with healthy stem cells. BMT is a medical procedure performed by a team of doctors and nurses in a specialized unit called the "Bone Marrow Transplantation Unit (BMTU)". It is not a surgical procedure.
The two terms "bone marrow transplant" and "stem cell transplant" are synonymous and are used interchangeably. "Hematopoietic stem cell transplant" is the most accepted terminology.
The Reason for Bone Marrow Transplantation
There are numerous types of stem cell transplants available, depending on the type of donor and the extent of the match.
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Autologous stem cell transplant
The child is his or her own donor in an autologous stem cell transplant. This is the preferred type of treatment for relapsed lymphoma and a few refractory solid tumours. Visit Manipal Hospitals for Bone Marrow Transplant Treatment in Yeshwanthpur.
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Allogenic stem cell transplant
Allogenic stem cell transplants use stem cells from another healthy person. This is the preferred type in bone marrow failure diseases, disorders of the immune system, and blood cancers.
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Umbilical cord blood transplant
Stem cells are taken from the umbilical cord soon after birth and preserved.
In certain conditions, BMT is the only curative treatment available. The diseases include:
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Aplastic anaemia (bone marrow failure).
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Primary immune deficiency (disorder of the immune system).
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Genetic diseases such as thalassemia and sickle cell disease (disorders where haemoglobin synthesis is affected).
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Relapsed or refractory leukaemia (blood cancer) and lymphoma (cancer of the lymphatic system).
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High-risk solid tumours like neuroblastoma (cancer of the Adrenal gland).
Steps in Bone Marrow Transplantation
The transplantation procedure is divided into 3 stages/phases:
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Preparatory Phase
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A healthy suitable donor is identified with a similar genetic (HLA) type. It can be a relative (sibling or parent) or an unrelated donor.
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Collection of stem cells from donor: The stem cells can be collected from blood similar to a simple blood donation called “Apheresis” or a “bone marrow harvest procedure”. To know more about the procedure, consult with the specialists in Yeshwanthpur.
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The patient is admitted to a specialized unit called Bone Marrow Transplant Unit (BMTU) which is a sterile zone of isolation which is “HEPA” (high-efficiency particulate absorption) filtered room where the patient will undergo treatment.
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Stem cell infusion and Engraftment
The stem cells collected from the donor is infused into patients similar to a blood transfusion under monitoring, These stem cells will become functional blood cells in due course
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Post-transplant Phase
It consists of meticulous follow-up of a patient to prevent complications like infections, etc
Complications might happen during and after stem cell transplant:
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Infections
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Graft dysfunction
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Graft-versus-host disease (GVHD) where there is abnormal immune response from donor stem cells.
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Blood transfusions
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Others like pain, mouth sores, diarrhea, vomiting, and weight loss or gain.
The Success of BMT
The success of BMT depends on the medical condition being treated, the type of transplantation, the experience of the treating team, and the facilities at the hospital. The success rate in treating conditions such as aplastic anaemia and thalassemia is as high as 80–95% of the time. In high-risk cancers, the success rate is often 60–65%.