A bone marrow transplant is performed by replacing the destroyed or damaged bone marrow with a new healthier bone marrow or stem cells.
Bone marrow is the spongy soft, fatty tissue present inside the bones. Bone marrow is responsible for the production of blood cells in the body. Stem cells are immature cells that are present inside the bone marrow that produce all types of different blood cells.
Being a complicated procedure, the risks involved in it are also severe which makes it a quite expensive treatment. The affordable cost of Bone marrow treatment in India brings a flow of international patients in the country.
This article focuses on describing different techniques that are used in bone marrow treatment in India.
Types of Bone Marrow Transplant
Patients might receive chemotherapy, radiotherapy or both before bone marrow transplant for managing or preparing them for the transplantation. This is usually done in two ways:
Ablative (myeloablative) treatment – uses high-dosage of chemotherapy or radiation therapy or both for killing cancer cells in the patient’s blood. These therapies also kill the remaining healthy cells present in the bone marrow, allowing new stem cells to grow inside the bone marrow.
Reduced intensity treatment aka mini-transplant – uses low-doses of radiation therapy and chemotherapy before the transplant. This is usually used for treating older patients, or patients with severe health complications.
There are ways in which bone marrow is retrieved for transplantation:
Autologous bone marrow transplantation – The word ‘auto’ means self. The stem cells are extracted from the patients before they are put radiation or chemotherapy, which are stored safely inside a freezer. Once the therapy cycles are complete, patients stem cells are inserted back inside the patient’s body for making healthy blood cells. This procedure is known as rescue transplant.
Allogeneic bone marrow transplant – ‘allo’ means other. In this treatment, the stem cells of another person (donor) are replaced with the damaged cells of the patient. The genes of the donor need to match with the patient. Several special tests are performed for ensuring that the donor is a good match for the patient. Usually, the patient’s sibling (brother/sister) is a good match. Sometimes parents, children, or other relatives can also be good matches. Unrelated donors, who are a good match can also be found through national bone marrow registries.
Umbilical-cord blood transplant – (a type of allogeneic transplantation) In this transplantation technique a newborn baby’s stem cells are removed from his/her umbilical cord right after his/her birth. These stem cells are stored until they are required for a transplant. The blood cells in the Umbilical cord are very immature, so usually, perfect matching is not necessary to implant them. However, due to the small ratio or number of stem cells in the umbilical cord, blood count can take very longto recover.
The stem cell transplant is performed after radiotherapy and chemotherapy cycles are complete. The stem cells are launched into the patient’s bloodstream using a central venous catheter (tube-like equipment) using a process which is similar to blood transfusion. The stem cells then travel through the blood slowly into the bone marrow. In most cases, surgery is not required for a Stem cell transplant.
There are two ways in which Donor stem cells is collected:
Bone marrow harvest – This technique requires a minor surgery which is performed under general anaesthesia so that the donor sleeps through the procedure without feeling any pain. Donor’s bone marrow is extracted from the back of both their hip bones. The amount of bone marrow removed during the harvest will depend on the patient’s weight who is receiving it.
Leukapheresis – In this technique, the donor is given shots of drugs that push stem cells to move into the blood from the bone marrow. Once a sufficient amount of stem cells start floating in the blood, a leukapheresis is performed. The donor’s blood is collected from their body using an IV line. Then the white blood cells containing the stem cells are separated from the blood in a machine and inserted inside the patient. Later, red blood cells can be returned inside the donor’s body.
Why is Bone Marrow Transplant performed?
A bone marrow transplant is used for removing damaged bone marrow by chemotherapy or radiation therapy, and then replacing it with healthy bone marrow or stem cells. Oncologists believe white cells can be helpful in attacking remaining cancer cells just like they fight viruses and infections.
A health care provider might recommend patients to undergo a bone marrow transplant if they have:
Any type of Cancer, including lymphoma, leukaemia, multiple myeloma or myelodysplasia.
The following diseases can affect the production of bone marrow/ stem cells:
Severe Immune System Illnesses
Sickle Cell Anemia