A bone marrow transplant, also called a stem cell transplant, is a procedure that infuses healthy cells, called stem cells, into your body to replace damaged or diseased bone marrow. A bone marrow transplant may also be used to treat certain types of cancer. A bone marrow transplant may be necessary if your bone marrow stops working and doesn't produce enough healthy stem cells.

Bone marrow transplants may use cells from your own body (autologous transplant) or from a donor (allogeneic transplant).

A bone marrow transplant may help you by:

  • Safely allowing treatment of your condition with high doses of chemotherapy or radiation
  • Replacing diseased or damaged marrow with new stem cells
  • Providing new stem cells, which can help kill cancer cells directly

Stem cell transplants can benefit people with a variety of both malignant (cancerous) and nonmalignant (noncancerous) diseases, including:

  • Acute leukemia
  • Adrenoleukodystrophy
  • Aplastic anemia
  • Bone marrow failure syndromes
  • Chronic leukemia
  • Hemoglobinopathies
  • Hodgkin's lymphoma
  • Immune deficiencies
  • Inborn errors of metabolism
  • Multiple myeloma
  • Myelodysplastic syndromes
  • Non-Hodgkin's lymphoma
  • Plasma cell disorders
  • POEMS syndrome
  • Primary amyloidosis

A stem cell transplant poses many risks of complications, some potentially fatal. The risk can depend on many factors, including the type of disease or condition, the type of transplant, and the age and health of the person. Although some people experience few problems with a transplant, others may develop complications that may require treatment or hospitalization. Some complications could even be life-threatening.

Complications that can arise with a stem cell transplant include:

  • Graft-versus-host disease (allogeneic transplant only)
  • Stem cell (graft) failure
  • Organ damage
  • Infections
  • Cataracts
  • Infertility
  • New cancers
  • Death

Your doctor can explain your risk of complications from a stem cell transplant. Together you can weigh the risks and benefits to decide whether a stem cell transplant is right for you.

Graft-versus-host disease: A potential risk when stem cells come from donors

If you receive a transplant that uses stem cells from a donor (allogeneic stem cell transplant), you may be at risk of graft-versus-host disease (GVHD). This disease happens when the donor stem cells that make up your new immune system see your body's tissues and organs as something foreign and attack them.

GVHD may happen at any time after your transplant. However, it's more common after your marrow has started to make healthy cells. Many people who have an allogeneic stem cell transplant get GVHD at some point. The risk of GVHD is a bit greater with unrelated donors, but it can happen to anyone who gets a stem cell transplant from a donor.

There are two kinds of GVHD: acute and chronic. Acute GVHD usually happens earlier, during the first months after your transplant. It typically affects your skin, digestive tract or liver. Chronic GVHD typically develops later and can affect many organs.

GVHD signs and symptoms include:

  • Joint or muscle pain
  • Shortness of breath
  • Persistent cough
  • Vision changes, such as dry eyes
  • Skin changes, including scarring under the skin
  • Rash
  • Yellow tint to your skin or the whites of your eyes (jaundice)
  • Dry mouth
  • Mouth sores
  • Abdominal pain
  • Diarrhea
  • Nausea
  • Vomiting

Pre-transplant tests and procedures

You'll undergo a series of tests and procedures to assess your health and the status of your condition, and to ensure that you're physically prepared for the transplant. The evaluation may take several days or more.

In addition, a surgeon or radiologist will implant a long thin tube (intravenous catheter) into a large vein in your chest or neck. The catheter, often called a central line, usually remains in place for the duration of your treatment. Your transplant team will use the central line to infuse the transplanted stem cells and other medications and blood products into your body.

Collecting stem cells for transplant

If an autologous stem cell transplant is planned, you'll undergo a procedure called apheresis (af-uh-REE-sis) to collect blood stem cells. Before apheresis, you'll receive daily injections of growth factor to increase stem cell production and move stem cells into your circulating blood so they can be collected.

During apheresis, blood is drawn from a vein and circulated through a machine. The machine separates your blood into different parts, including stem cells. These stem cells are collected and frozen for future use in the transplant. The remaining blood is returned to your body.

If an allogeneic stem cell transplant is planned, you will need a donor. When you have a donor, stem cells are gathered from that person for the transplant. This process is often called a stem cell harvest or bone marrow harvest. Stem cells can come from your donor's blood or bone marrow. Your transplant team decides which is better for you based on your situation.

The conditioning process

After you complete your pre-transplant tests and procedures, you begin a process known as conditioning. During conditioning, you'll undergo chemotherapy and possibly radiation to:

  • Destroy cancer cells if you are being treated for a malignancy
  • Suppress your immune system
  • Prepare your bone marrow for the new stem cells

The type of conditioning process you receive depends on a number of factors, including your disease, overall health and the type of transplant planned. You may have both chemotherapy and radiation or just one of these treatments as part of your conditioning treatment.

Side effects of the conditioning process can include:

  • Nausea and vomiting
  • Diarrhea
  • Hair loss
  • Mouth sores or ulcers
  • Infection
  • Bleeding
  • Infertility or sterility
  • Anemia
  • Fatigue
  • Cataracts
  • Organ complications, such as heart, liver or lung failure

You may be able to take medications or other measures to reduce such side effects.

Reduced-intensity conditioning

Based on your age and health history, it may be better for you to receive lower doses or different types of chemotherapy or radiation for your conditioning treatment. This is called reduced-intensity conditioning.

Reduced-intensity conditioning kills some cancer cells and somewhat suppresses your immune system. Then, the donor's cells are infused into your body. Donor cells replace cells in your bone marrow over time. Immune factors in the donor cells may then fight your cancer cells.

During your stem cell transplant

After conditioning, the stem cell transplant can take place. On the day of your transplant, called day zero, you are given the stem cells through your central line using a process known as infusion. The transplant infusion is painless. You are awake during the procedure.

The transplanted stem cells make their way to your bone marrow, where they begin creating new blood cells. It can take a few weeks for new blood cells to be produced and for your blood counts to begin recovering.

Bone marrow or blood stem cells that have been frozen and thawed contain a preservative called dimethyl sulfoxide (DMSO) that protects the cells. Just before the transplant, you may receive medications to reduce the side effects the preservative may cause. You'll also likely be given IV fluids (hydration) before and after your transplant to help rid your body of the preservative. Side effects of DMSO may include:

  • Nausea
  • Fever
  • Diarrhea
  • Chills
  • Hives
  • Red urine

Not everyone experiences side effects from the preservative, and for some people those side effects are minimal.

After your stem cell transplant

When the new stem cells enter your body, they begin to travel to your bone marrow. In time, they multiply and begin to make new, healthy blood cells. This is called engraftment. It usually takes several weeks before the number of blood cells in your body starts to return to normal. In some people, it may take longer.

In the days and weeks after your stem cell transplant, you'll have blood tests and other tests to monitor your condition. You may need medicine to manage complications, such as nausea and diarrhea.

After your stem cell transplant, you'll remain under close medical care. If you're experiencing infections or other complications, you may need to stay in the hospital for several days or sometimes longer. Depending on the type of transplant and the risk of complications, you'll need to remain nearby for several weeks to months to allow close monitoring.

You may also need periodic transfusions of red blood cells and platelets until your bone marrow begins producing enough of those cells on its own.

You may be at greater risk of infections or other complications for months to years after your transplant.

A stem cell transplant can cure some diseases and put others into remission. Goals of a stem cell transplant depend on your individual situation, but usually include controlling or curing your disease, extending your life, and improving your quality of life.

Some people complete stem cell transplantation with few side effects and complications. Others experience numerous challenging problems, both short and long term. The severity of side effects and the success of the transplant vary from person to person and sometimes can be difficult to predict before the transplant.

It can be discouraging if significant challenges arise during the transplant process. However, it is sometimes helpful to remember that there are many survivors who also experienced some very difficult days during the transplant process but ultimately had successful transplants and have returned to normal activities with a good quality of life.

May 05, 2015