Bone Marrow (Stem Cell) Transplant

What is a bone marrow transplant?

A bone marrow transplant is also known as a stem cell transplant or hematopoietic stem cell transplant. It is a medical procedure to replace bone marrow that has been damaged by disease, infection or chemotherapy.

Bone marrow is the spongy, fatty tissue inside your bones. It holds hematopoietic stem cells that are able to make new blood cells. In broad terms, our bodies have 3 types of blood cells:

• Red blood cells (haemoglobin), which carry oxygen and nutrients around your body
• White blood cells, which fight infections
• Platelets, which prevent excessive bleeding through clotting

During the transplant, healthy stem cells are introduced into your bloodstream so that they can travel to your bone marrow, produce new blood cells and promote the growth of new marrow.

Types of bone marrow transplants

Depending on the source of healthy stem cells, there are 2 types of transplants:

1. Allogeneic transplant, where the source of the healthy stem cells is another person.
2. Autologous transplant, where the source of the healthy stem cells is yourself (before you start chemotherapy or radiation treatment)

Why do you need a bone marrow transplant?

Bone marrow transplants are used to treat medical conditions that damage the bone marrow, such as:

• Anaemia, caused by bone marrow failure
• Leukemia, a type of cancer affecting white blood cells
• Lymphoma, a different type of cancer affecting white blood cells
• Myeloma, a type of cancer affecting plasma cells (a specific type of white blood cells that produce antibodies)
• Certain blood, immune system and metabolic disorders

Bone marrow transplants can also repair bone marrow that was damaged due to intensive cancer treatment.

Your doctor will only recommend a bone marrow transplant if other treatments have not been effective, and you are in relatively good health despite your condition.

Who should not undergo a bone marrow transplant?

In general, age does not affect your eligibility for a bone marrow transplant. However, you may be ineligible if you have other major health problems such as serious heart, lung, liver, or kidney disease.

What are the risks and complications of a bone marrow transplant?

Bone marrow transplants are complex procedures with significant risks. Your doctor will discuss the risks and possible benefits to help you decide whether to proceed.

Complications that may occur with bone marrow transplants include:

• Graft versus host disease (GvHD). This occurs in allogeneic transplants when the transplanted cells start attacking other cells.
• Infections. As bone marrow transplants weaken your immunity, you may face a higher risk of infection while your body recovers.
• Low platelets and low red blood cells, which may result from non-functioning bone marrow. Low platelets can cause dangerous internal bleeding.
• Pain. High doses of chemotherapy and radiation can cause inflammation of the mouth and gastrointestinal (GI) tract, leading to painful mouth sores and GI irritation.
• Fluid overload, where the kidney cannot cope with the large amount of fluid being given in the form of intravenous (IV) medicine, nutrition and blood products.
• Respiratory distress, which may occur if there is infection or inflammation of the airway.
• Organ damage. The liver and heart are important organs that may be damaged during the transplantation process.