What is Bone Marrow Transplant? How is a Bone Marrow Transplant Performed?

What is Bone Marrow Transplantation?

A bone marrow transplant, also known as a stem cell transplant, is a procedure in which healthy blood-forming stem cells, either from the person themselves or from a donor, are injected into the body to replace bone marrow that is unable to produce enough healthy blood cells. In this way, new red blood cells, white blood cells and platelets are produced and the immune system becomes functional again.

Bone marrow transplantation is a treatment method that can be applied in both adult and pediatric bone marrow transplant centers and varies according to age groups. In adult centers, diseases such as leukemia, lymphoma, and multiple myeloma are mostly treated; in pediatric centers, congenital bone marrow deficiencies, immune system disorders, and hereditary metabolic diseases are treated.

Why is Bone Marrow Transplant Performed?

A bone marrow transplant is done to restore blood cell production by replacing damaged or non-functioning bone marrow with healthy stem cells. The procedure is used in the treatment of diseases such as leukemia, lymphoma, aplastic anemia, hereditary blood and immune disorders, and to repair the marrow after high-dose cancer treatment.

Reasons for bone marrow transplantation include:

• Treating bone marrow failure (e.g., aplastic anemia)
• Rebuilding bone marrow after high-dose cancer therapy
• Treating cancers such as leukemia, lymphoma, and multiple myeloma
• Correcting inherited blood disorders such as thalassemia, sickle cell anemia, and Fanconi anemia
• Treating immune system disorders (e.g., SCID, Wiskott–Aldrich syndrome)
• Treating some metabolic or autoimmune diseases
• Taking advantage of the "graft-versus-tumor" effect of donor cells against tumors in allogeneic transplantation

What are the Types of Bone Marrow Transplantation?

Types of bone marrow transplantation include:There are autologous transplants using the patient's own cells, allogeneic transplants using cells from a compatible donor, syngeneic transplants from a twin with a perfect genetic match, transplants from umbilical cord blood, and haploidentical transplants from partially compatible relatives.

The types of bone marrow transplants are as follows:

• Autologous Transplant
• Allogeneic Transplant
• Syngeneic Transplant
• Umbilical Cord Blood Transplant
• Haploidentical Transplant

Autologous Transplant

In an autologous transplant, the patient's own stem cells are used. First, the stem cells are collected and frozen. The patient then receives high-dose chemotherapy or radiotherapy. Following these treatments, the patient's own stem cells are reintroduced to the bone marrow, "rescuing" it and starting to produce new blood cells.

Allogeneic Transplant

In an allogeneic transplant, stem cells are collected from a compatible donor. The donor is usually a sibling, relative, or a suitable person from the international donor pool. Thanks to this method, the patient not only receives new blood cells, but also a “graft-versus-tumor” effect can be created against diseased cells through the immune system of the donor cells.

Syngeneic Transplantation

Syngeneic transplantation is a special procedure that can only be performed between identical twins. Since the genetic structure is completely identical, there is almost no risk of tissue incompatibility or immune system conflict. However, this method is very rarely applied because the appropriate condition can only be met in twin siblings.

Umbilical Cord Blood Transplantation

Umbilical cord blood transplantation uses stem cells collected from the umbilical cord after birth. Because these cells are younger and immature, the adaptation criteria are more flexible. However, the engraftment process, that is, settling into the bone marrow, may be longer. It is a method frequently used especially in pediatric patients.

Haploidentical Transplant

A haploidentical transplant is performed using stem cells taken from a semi-compatible first-degree relative (mother, father, child, or sibling). It provides an important alternative when a fully compatible donor cannot be found or when urgent transplantation is required. Thanks to modern immunological treatments, the success rate of such transplants is gradually increasing.

Before a Bone Marrow Transplant

Before a bone marrow transplant, the patient undergoes chemotherapy or radiotherapy to cleanse the existing bone marrow and provide a suitable environment for the establishment of new stem cells.

How is a Bone Marrow Transplant Performed?

A bone marrow transplant begins with the collection of healthy stem cells from a suitable donor or from the patient herself. Stem cells are obtained from the donor's bone marrow using a needle or by withdrawing them from the bloodstream with a special device. The collected stem cells are transferred through a catheter placed in a vein in the patient's neck, in a process similar to a blood transfusion. After these stem cells enter the bloodstream, they reach the bone marrow and begin to produce healthy blood cells.

In Which Diseases Is Bone Marrow Transplant Used?

Bone marrow transplantation is usually used in the treatment of cancer, blood diseases and some genetic disorders. Major areas of application include conditions such as leukemia, lymphoma, multiple myeloma, aplastic anemia, and sickle cell disease. Additionally, bone marrow transplantation may be a treatment option for some immune system disorders. This transplant is done to help the body produce healthy blood cells and rebuild the immune system.

Bone marrow transplantation is used in the following areas:

• Acute and chronic leukemia,
• Lymphoma (Hodgkin's and non-Hodgkin's lymphomas),
• Multiple myeloma,
• Aplastic anemia,
• Thalassemia (Mediterranean anemia),
• Sickle cell anemia,
• Myelodysplastic syndrome (MDS),
• Immunodeficiency diseases,
• Some inherited metabolic diseases.
• Autoimmune diseases (in treatment-resistant cases).

Why is Bone Marrow Transplant Performed?

Bone marrow transplantation is performed to restore the body's function when it is unable to produce healthy blood cells. For example, when the bone marrow is damaged or loses its function due to cancer types such as leukemia, lymphoma, aplastic anemia, multiple myeloma, or genetic blood diseases, this problem is tried to be resolved by transplanting healthy stem cells. The transplant replenishes the patient's blood cells, strengthening the immune system, increasing the ability to fight infections and supporting the production of healthy blood cells.

Reasons for bone marrow transplantation include:

• To regenerate healthy cells after cancer treatment,
• To replace diseased cells in blood cancers such as leukemia,
• To support treatment in cancers such as lymphoma and multiple myeloma,
• To treat conditions involving insufficient blood cell production, such as aplastic anemia,
• To alleviate the symptoms of inherited blood disorders such as sickle cell anemia,
• To replace missing healthy blood cells in genetic diseases such as thalassemia,
• To strengthen the immune system in cases of advanced immunodeficiency,
• To repair damage to the immune system caused by chemotherapy or radiation therapy,
• To rebuild the immune system in some autoimmune diseases,
• To correct cell disorders such as myelodysplastic syndrome (MDS).

How Many Days Does It Take for a Bone Marrow Donor to Recover?

The healing process of the marrow donor begins after the bone marrow is collected. Before a bone marrow transplant, the donor usually undergoes a series of medical tests and is evaluated for general health. Usually, results from blood tests, imaging tests, and a physical exam determine whether a person is suitable for a transplant. The recovery time of the marrow donor depends on the results of the tests and the plan determined for the transplant.

The Recovery Process

The most significant step in the recovery process for a bone marrow donor is the collection of bone marrow. The marrow collection procedure is usually performed under general anesthesia or sedation and usually takes several hours. During the procedure, bone marrow samples are usually taken from the patient's pelvis (hip bone) area. This procedure is generally minimally invasive, and post-surgical recovery time is usually quick.

The marrow donor begins the recovery process immediately after the bone marrow collection procedure. The patient usually regains consciousness within a few hours after the procedure and may be kept under observation for a few hours in the hospital. The healing process can often be aided by medications such as painkillers or anti-inflammatory drugs. Rest and avoidance of certain activities may also be recommended to speed up the healing process.

During the recovery process, symptoms may occur after the bone marrow collection procedure. These symptoms may include mild pain, swelling, or tenderness. These symptoms usually subside within a few days and are considered part of the healing process.

The healing process also depends on the general health of the marrow donor. Some people may experience mild side effects related to the bone marrow collection procedure, which may last longer. These may include fatigue, headache, or mild fever. Such side effects usually go away on their own within a few days.

However, if any complications occur, the marrow donor should consult their doctor. In rare cases, serious complications can occur after bone marrow collection. In this case, the marrow donor may require further medical intervention.

Can a person who donates marrow donate again?

It is possible for a marrow donor to donate his or her marrow again, but the frequency and conditions of this donation are subject to certain protocols. The marrow donation process is generally evaluated based on a person's health status, age, gender, and suitability to be a donor.

Before the marrow donor can donate again, his/her health condition is first evaluated. People who are healthy and willing to donate again can donate their marrow again after a certain period of time. However, this period is usually several years and may be done at certain intervals to protect the donor.

Another factor that influences whether a donor will donate marrow again is whether the donor's previous donation was accepted by the recipient. If the previous transplant to the donor was successful and the recipient needs a new transplant, the same donor can donate his or her marrow again.

However, the process of donating marrow again may be different from the process of donating it for the first time. For example, before donating marrow again, the donor's health status is re-evaluated and necessary tests are performed.

The possibility of a marrow donor donating again raises awareness about the importance and impact of being a donor. Marrow donation is a form of kindness and support that can save lives or improve the quality of life. Therefore, the value and importance of giving should be emphasized and encouraged in society.

Possible Risks of Bone Marrow Transplantation

Bone marrow transplantation is a medical procedure that carries certain risks. However, these risks are generally low and successful outcomes are achieved in many patients. During bone marrow transplantation, some risks and complications may arise. Some of these include nausea, vomiting, fever and fatigue. Serious risks include immune system problems, blood clots, and serious infections.

Possible risks of bone marrow transplantation include:

• Nausea
• Vomiting
• Fever
• Fatigue
• Immune system problems
• Blood clots
• Serious infections
• The body's rejection of new cells

Frequently Asked Questions About Bone Marrow Transplantation

What are stem cells?

A stem cell is a special type of cell that has the ability to transform into all types of cells in the body and renew itself. These cells can differentiate into various cells such as blood, muscle, nerve and skin cells when necessary, and thus play an important role in the repair of damaged tissues in the body. Stem cells are found especially densely in bone marrow, cord blood and some tissues and are used as a promising treatment option in medical treatments, especially for blood diseases, immune system problems and tissue damage.

What is bone marrow?

Bone marrow is a soft, spongy tissue found inside bones. Bone marrow, the center of blood cell production, produces red blood cells, white blood cells and platelets, which are vital for the body. There are two types of bone marrow: red bone marrow (hematopoietic) and yellow bone marrow (stromal). Red bone marrow is responsible for the production of blood cells, while yellow bone marrow (stromal) consists mostly of fat cells and serves as an energy storage facility. It is necessary for the healthy functioning of the bone marrow, immune system and blood circulation.

Where is bone marrow located?

Bone marrow is a soft tissue found in the spongy tissue inside bones. The large bones of the body, especially the hipbone, spine, sternum, ribs, and femur, contain large amounts of bone marrow. This tissue is vital as it is where blood cells are produced and ensures the formation of red and white blood cells and platelets.

What are the benefits of bone marrow transplantation?

A bone marrow transplant replaces damaged or dysfunctional bone marrow with healthy stem cells, restarting the body's production of new blood cells. This procedure is used to treat serious diseases that affect the bone marrow, such as leukemia, lymphoma, and other blood or immune system diseases. Thanks to healthy stem cells, the body can better defend against infections, blood cells are produced at normal levels and the patient's overall quality of life improves.

What is done before bone marrow transplant?

Before the bone marrow transplant, drug treatments such as chemotherapy and sometimes radiotherapy are used to destroy the patient's damaged or abnormal stem cells. These treatments increase the success of the transplant by preparing the patient's bone marrow for the placement of new, healthy stem cells. It also suppresses the immune system, reducing the risk of the body rejecting the transplanted cells.

What happens after bone marrow transplant?

Although patients generally do well after a bone marrow transplant, they may experience various side effects during the first 30 days. These side effects are carefully monitored by the doctor and medication support is provided to reduce them. The transplanted stem cells reach the bone marrow shortly after the procedure and begin producing new blood cells and rebuilding the immune system. After the transplant, the medical team regularly monitors the patient's blood values, performs necessary checks, and supports the treatment process.

Are there any side effects of bone marrow transplantation?

Bone marrow transplantation may cause some side effects. In the first period after transplantation, the risk of infection increases in patients, and digestive system problems such as nausea, vomiting, diarrhea, and mouth sores may occur. Additionally, side effects such as skin rashes, hair loss, and fatigue may also occur. With allogeneic transplants, a condition called graft-versus-host disease (GVHD) can develop when the immune system rejects the transplanted cells. Side effects are monitored under physician supervision and managed with medication when necessary.

What is the generation process in bone marrow transplantation?

The generation process in bone marrow transplantation includes the stages of cell proliferation and the creation of functional tissues. In the first-generation process, healthy cells grown in a laboratory environment are placed into diseased tissues, thus enabling the production of blood cells and the reconstruction of the immune system. The second-generation procedure utilizes biomaterials. These biomaterials with a three-dimensional structure act as a framework that supports tissue and cell formation. Biomaterials provide a homogeneous distribution of cells and offer a dissolution property compatible with the host tissue. These two stages support tissue regeneration, increasing the success of bone marrow transplantation.

Are bone marrow transplantation and stem cell transplantation the same?

The terms bone marrow transplant and stem cell transplant are often used interchangeably, but they do not mean exactly the same thing. Bone marrow transplantation refers to the transplantation of stem cells directly from the bone marrow. Stem cell transplantation is a broader term that includes the transplantation of stem cells from different sources, namely bone marrow, blood circulation (peripheral stem cells) or cord blood, into the patient. Nowadays, stem cell transplants are more commonly performed, especially via peripheral stem cell transplantation, because this method is less invasive.

Can stem cells be taken from someone else in a bone marrow transplant?

Yes, stem cells can be taken from someone else. Stem cell transplantation can be performed with stem cells taken from a compatible donor, a semi-compatible donor, or directly from the patient herself. Compatible donors are usually family members or compatible donors who have passed compatibility tests, but stem cell transplantation can also be performed from partially compatible donors if necessary.