Bone marrow transplant is a procedure that implants stem cells that make healthy blood into the body to replace damaged or diseased bone marrow. In cases where the bone marrow does not work or cannot produce enough healthy blood cells, a bone marrow transplant is required. Bone marrow transplants are of two types, autologous and allogeneic. Transplants using cells from the human body are called autologous transplants, and transplants from a donor or donor are called allogeneic transplants.
Autologous stem cell transplant
Autologous stem cell transplant uses healthy blood stem cells in the body to replace the diseased or damaged bone marrow. During stem cell transplantation, using cells from one's own body has some advantages over using stem cells from another person. For example; In autologous stem cell transplants, there is no incompatibility problem between the transplanted cells and the body's own cells.
Autologous bone marrow transplantation may only be an option if the body is producing enough healthy bone marrow cells. These cells can be collected, frozen and stored for later use. Autologous stem cell transplants are often used in people who need high doses of chemotherapy and radiation. Autologous stem cell transplantation helps replace damaged bone marrow.
Autologous stem cell transplant is mostly used to treat the following conditions:
• Hodgkin lymphoma
• Myeloma
• Non-Hodgkin lymphoma
• Plasma cell disorders
• Allogeneic stem cell transplant
• Allogeneic stem cell transplant uses healthy "blood stem cells" from a donor to replace diseased or damaged bone marrow. Allogeneic stem cell transplant is also called allogeneic bone marrow transplant.
• Donor; It could be a family member, acquaintance or a stranger.
Cells used in allogeneic stem cell transplantation can be collected from different regions as follows:
• From donor's blood
• Bone marrow within the donor's hipbone
• From donated umbilical cord blood
Before allogeneic stem cell transplantation is performed, high doses of chemotherapy or radiation therapy are taken to destroy diseased cells and prepare the body for donor cells. An allogeneic stem cell transplant may be an option for people with a variety of diseases, including:
• Acute leukemia
• Adrenoleukodystrophy
• Extreme anemia
• Bone marrow failure syndromes
• Chronic leukemia
• Hemoglobinopathies
• Hodgkin lymphoma
• Immune deficiencies
• Inborn errors of metabolism
• Multiple myeloma
• Myelodysplastic syndromes
• Neuroblastoma
• Non-Hodgkin lymphoma
• Plasma cell disorders
• POEMS syndrome
• Primary amyloidosis
PRETRANSPLANT TESTS AND PROCEDURES
Before a bone marrow transplant, a series of tests and procedures are performed to evaluate the general health of the patient and to make sure he is physically ready for the transplant. The assessment can take a few days or longer. Apart from this, a surgeon or radiologist inserts a long, thin tube (intravenous catheter) into a large vein in the chest or neck. The catheter usually stays in place for the duration of the treatment. The transplant team will use this catheter to deliver the transplanted stem cells, medications, and blood products into the body.
STEM CELL COLLECTION FOR AUTOLOGICAL TRANSMISSION
If a transplant using one's own cells (autologous transplant) is planned, a procedure called apheresis is used to collect blood stem cells. Before apheresis, growth factor injections are administered daily to increase stem cell production and transport the stem cells to the circulating blood so that they can be collected.
During apheresis, blood is taken from a vein and circulated in a special machine. The machine divides the blood into different parts, including stem cells. Stem cells are collected and frozen for use during transplantation. The remaining blood is sent back to the body.
COLLECTION OF STEM CELLS FOR ALLOGENIC TRANSMISSION
In a transplant that uses stem cells from a donor (allogeneic transplant), a suitable donor is searched for and, when found, procedures for stem cell harvesting are performed. Stem cells can come from the donor's blood or bone marrow. The transplant team decides which one is better based on the patient's condition.
Another type of allogeneic transplant uses stem cells from umbilical cords (cord blood transplant). Mothers can choose to donate their umbilical cord after the birth of their baby. The blood from these cords is frozen and stored in the cord blood bank until a bone marrow transplant is required.
PREPARATION OR CONDITIONING PROCESS
After the pre-transplant tests and procedures are completed, a process known as the conditioning regimen is started. During conditioning, chemotherapy or radiation is applied to ensure:
• Destroying cancerous cells
• Suppressing the immune system
• Preparing the bone marrow for new stem cells
The conditioning regime to be taken; It depends on a number of factors such as illness, general health and the type of transplant planned.
What happens during a bone marrow transplant?
Bone marrow transplant takes place after completing the conditioning process. On the day of transplant, stem cells are given to the body through the catheter. The transplant is painless and the patient is not put to sleep during the procedure.
After a bone marrow transplant
When new stem cells enter the body, they travel from the blood to the bone marrow. Over time, they multiply and begin to make new, healthy blood cells. While it usually takes a few weeks for the number of blood cells in the body to return to normal, it may take longer in some people.
It is important to closely monitor the patient's condition in the days and weeks after having a bone marrow transplant. For this, some blood and similar tests can be applied to the patient. Complications such as nausea and diarrhea may be observed and medication may be required to cure them.
After a bone marrow transplant, close medical care is required. If infection or other complications occur, it may be necessary to stay in the hospital for several days, or sometimes longer.
Until the bone marrow begins to produce enough healthy cells on its own, the patient may require periodic transfusions of red blood cells and platelets.
Even months or years after the transplant, patients may be at a higher risk of infection or other complications. Periodic lifelong follow-up appointments are required to monitor late complications.
Things to watch out for after transplant
If the bone marrow transplant uses stem cells from a donor (allogeneic transplant), doctors may prescribe medications that reduce the immune system's reaction (immunosuppressive drugs) to prevent Graft-versus-Host Disease (GVHD). It takes time for the immune system to recover after transplantation. During this time, medications may also be given to prevent infections.
After a bone marrow transplant, dietary adjustments may be necessary to stay healthy and prevent excessive weight gain. The nutritionist (dietician) and other members of the transplant team work with the patient to create a healthy eating plan that meets needs and complements their lifestyle. Some of the suggestions may include:
• Following food safety instructions to prevent foodborne infections
• Eating a wide variety of healthy foods, including vegetables; fruits; whole grains; lean meat, poultry and fish; legumes; and healthy oils like olive oil
• Limiting salt intake
• Restricting alcohol
• Avoiding grapefruit and grapefruit juice because of its effects on a group of immunosuppressive drugs (calcineurin inhibitors)
• Regular physical activity after bone marrow transplant; It helps to control weight, strengthen bones, increase stamina, strengthen muscles and keep the heart healthy.
It is even more important to take steps to prevent cancer after a transplant. It is important not to smoke, to use sunscreen when you are out, and to have cancer screenings recommended by the doctor.
Bone marrow transplant results
Bone marrow transplants can cure some diseases and put others into remission. Some people complete a bone marrow transplant with few side effects and complications. Others face numerous tough challenges, both in the short and long term. The severity of side effects and the success of the transplant vary from person to person and can sometimes be difficult to predict before transplant.
It can be discouraging if significant difficulties arise during the transplant process. However, it can sometimes be helpful to remember that there are many people who have had a very difficult time during the transplant process but ultimately have successful transplants and are returning to normal activities with a good quality of life.