Marrow Transplant

Bone Marrow Transplantation: Types, Procedure, and Donor Requirements

Bone marrow transplantation (also referred to as stem cell transplantation) is a life-saving medical procedure that plays a vital role in the treatment of hematological diseases, including both cancerous and non-cancerous blood disorders. Thanks to advancements in medical technologies, stem cells can now be obtained not only from the bone marrow, but also from peripheral blood and umbilical cord blood, enhancing the effectiveness of treatments.

What Is Bone Marrow Transplantation?

This elite therapeutic method involves the infusion of healthy stem cells into a patient whose bone marrow is not functioning properly. Depending on the source of the stem cells, the procedure is classified into:

• Bone Marrow Transplantation
• Peripheral Blood Stem Cell Transplantation
• Cord Blood Transplantation

If the patient’s own stem cells are used, it is called autologous stem cell transplantation. When stem cells are collected from a genetically compatible healthy donor, the procedure is termed allogeneic stem cell transplantation. Each type comes with its own application techniques and potential risks. Over 4,000 stem cell transplants are performed annually in our country alone.

Which Diseases Are Treated With Bone Marrow Transplants?

Stem cell transplantation is primarily used in treating blood cancers such as leukemias, lymphomas, and multiple myeloma. It is also effective in treating conditions such as:

• Bone marrow failure syndromes
• Inherited diseases like thalassemia
• Certain solid organ cancers
• Immune system disorders

Autologous Stem Cell Transplantation

In autologous transplantation, stem cells are harvested from the patient before high-dose chemotherapy and/or radiotherapy. These treatments aim to eliminate the cancer cells. After treatment, the patient’s own previously collected stem cells are reinfused to help the bone marrow recover and regenerate healthy blood cells.

Allogeneic Stem Cell Transplantation

Unlike autologous transplantation, allogeneic stem cell transplantation involves the use of stem cells from a compatible donor. After high-dose chemotherapy or radiation destroys the diseased bone marrow, healthy stem cells from the donor are transplanted to replace the patient’s damaged or destroyed marrow. This method offers an additional therapeutic effect known as the “graft-versus-tumor” effect, where donor cells help attack any remaining cancer cells.

Who Can Be a Bone Marrow Donor?

A common misconception is that the blood types of the donor and recipient must match. However, bone marrow transplants can be performed between people with different blood groups. The critical factor is HLA tissue compatibility—the closer the tissue match, the higher the chances of a successful transplantation and fewer complications such as rejection or graft-versus-host disease.

How Are Bone Marrow Stem Cells Collected?

Bone marrow harvesting is typically carried out under general anesthesia in a sterile operating room environment. Using specialized needles, doctors access the pelvic bone and draw marrow into syringes. After being processed and filtered, the collected stem cells are intravenously infused into the patient.

Bone marrow transplantation represents a powerful treatment option that continues to evolve, offering hope and extended survival to patients with a wide range of life-threatening diseases.