Stem Cell Transplantation

Stem cell transplantation is a treatment method that involves transferring healthy stem cells to replace damaged or non-functional ones. Before the procedure, high-dose chemotherapy or radiotherapy may be administered to prepare the body for the transplant. The transplanted stem cells travel through the bloodstream and settle in the bone marrow, where they begin to multiply and produce healthy blood cells. The success of the transplantation process is closely monitored through daily blood counts.

What Are Stem Cells?

Stem cells are unique cells in the body with the potential to transform into different types of specialized cells. They serve as the body’s natural repair system, helping to regenerate and replace damaged tissues. There are two main types of stem cells: embryonic stem cells and adult stem cells. Unlike other cells, stem cells have the ability to develop into muscle cells, blood cells, or even brain cells, depending on the body’s needs.

What Is Stem Cell Transplantation?

Stem cell transplantation is a medical procedure performed when the bone marrow, responsible for producing blood cells, loses its function. In this process, healthy stem cells are delivered to the patient through intravenous infusion. It is commonly used in the treatment of conditions such as leukemia, lymphoma, and certain types of bone marrow failure. The transplant helps rebuild the immune system by restoring the body’s ability to produce healthy blood cells.
Stem cell transplantation can be categorized as either autologous (using the patient’s own stem cells) or allogeneic (using stem cells from a compatible donor). After the procedure, daily blood counts are monitored closely to evaluate the effectiveness of the transplant.

Who Can Benefit from Stem Cell Transplantation?

Stem cell transplantation can be applied to individuals with blood disorders or weakened immune systems. However, it is only suitable for patients who meet specific clinical criteria. The following patient groups may benefit from stem cell transplantation:

• Patients with blood cancers such as leukemia, lymphoma, and multiple myeloma
• Individuals with bone marrow failure, including aplastic anemia
• Patients with thalassemia or other inherited metabolic disorders
• Those who have developed bone marrow damage due to prior chemotherapy or radiotherapy

To be eligible for stem cell transplantation, a patient’s overall health status, age, presence of comorbidities, and tissue compatibility are carefully evaluated. The treatment plan is then tailored to meet the individual’s specific medical needs.

What Are the Types of Stem Cell Transplantation?

The types of stem cell transplantation may vary depending on the patient’s medical needs, the nature of the disease, and overall health status. The success rate of transplantation is closely linked to selecting the most appropriate method. Therefore, determining the optimal approach requires a thorough evaluation by medical specialists.
Stem cell transplants are generally classified into four main categories based on the source and method of application:

Autologous Stem Cell Transplantation

In autologous transplantation, a patient’s own healthy stem cells are collected and frozen. After receiving high-dose chemotherapy or radiotherapy, the preserved stem cells are reinfused. This method is commonly used in cancers such as multiple myeloma and lymphoma.

Allogeneic Stem Cell Transplantation

Allogeneic transplantation involves transferring stem cells from a donor who is a close tissue match to the recipient. It is widely used in conditions such as leukemia and bone marrow failure, with the aim of reestablishing a functioning immune system.

Haploidentical Transplantation

Haploidentical transplantation is a subtype of allogeneic transplant, where the donor is a partial genetic match (typically 50%). Parents or children are often considered as suitable donors. This option expands donor availability for patients in need.

Umbilical Cord Blood Transplantation

This method uses stem cells derived from cord blood collected immediately after birth. It is particularly effective for pediatric patients. Although it has lower requirements for tissue compatibility and carries a reduced infection risk, the recovery process may be slower compared to other transplant types.

How Are Stem Cells Collected and Applied?

Before a stem cell transplant can take place, stem cells must be collected safely from a suitable source. Once harvested, they are preserved under appropriate conditions and administered to the patient at the right time. The method of application varies depending on the patient’s needs and the origin of the stem cells.
Stem cells are typically obtained from three main sources:

Peripheral Blood (Circulatory System)

One of the most commonly used methods involves peripheral blood. Donors receive growth factor injections to stimulate the movement of stem cells from the bone marrow into the bloodstream. The blood is then drawn through a process called apheresis, which separates the stem cells from other blood components.

Bone Marrow

Stem cells can also be collected directly from the donor’s pelvic bone through aspiration. This method is often preferred for pediatric patients and in certain specific clinical cases.

Umbilical Cord Blood

Cord blood, collected from the umbilical cord immediately after birth, is rich in stem cells. These cells are cryopreserved in laboratory conditions and are commonly used for transplants, especially in children.

In Which Diseases Is Stem Cell Transplantation Used?

Stem cell transplantation is a medical procedure used when the bone marrow loses its ability to produce healthy blood cells. This intervention helps to restore normal blood cell production by introducing healthy stem cells into the body. Particularly effective in treating blood-related and immune system disorders, stem cell transplantation can be applied in both adults and children with significant success.
The main conditions treated with stem cell transplantation include:

• Leukemia
• Lymphoma
• Aplastic anemia
• Sickle cell anemia
• Thalassemia (Mediterranean anemia)
• Myelodysplastic syndrome
• Multiple myeloma
• Neuroblastoma and certain pediatric cancers
• Advanced-stage immune deficiencies
• Specific genetic and metabolic disorders

Frequently Asked Questions About Stem Cell Treatment

What are the side effects of stem cell transplantation?

Potential side effects following stem cell transplantation may include body aches, gastrointestinal issues, loss of appetite, altered taste perception, skin changes, and hair loss. The severity and duration of these effects can vary depending on the patient’s overall condition and the type of transplant received.

Who is not eligible for stem cell transplantation?

Stem cell transplantation is only performed after comprehensive medical evaluation and diagnostic testing. It is generally not recommended during pregnancy or breastfeeding, as the safety of stem cell therapy in these periods has not been clearly established.

How long does stem cell transplantation take?

The stem cell transplant process typically lasts between 7 and 10 days. This period includes a preparatory regimen, usually followed by the transplantation procedure on the second or third day. The stem cells are infused into the patient through a previously placed central line or a newly accessed vein.