What is a Bone Marrow Transplant (Stem Cell Transplant)?

Approved by the Cancer.Net Editorial Board, 08/2018

A bone marrow transplant, also called a stem cell transplant, is a treatment for some types of cancer. For example, you might have one if you have leukemia, multiple myeloma, or some types of lymphoma. Doctors also treat some blood diseases with stem cell transplants.

In the past, a stem cell transplant was more commonly called a bone marrow transplant because the stem cells were collected from the bone marrow. Today, stem cells are usually collected from the blood, instead of the bone marrow. For this reason, they are now often called stem cell transplants.

Why are bone marrow and stem cells important?

A part of your bones called “bone marrow” makes blood cells. Marrow is the soft, spongy tissue inside bones. It contains cells called “hematopoietic” stem cells (pronounced he-mah-tuh-poy-ET-ick). These cells can turn into several other types of cells. They can turn into more bone marrow cells. Or they can turn into any type of blood cell.

Certain cancers and other diseases keep hematopoietic stem cells from developing normally. If they are not normal, neither are the blood cells that they make. A stem cell transplant gives you new stem cells. The new stem cells can make new, healthy blood cells.

Types of stem cell transplant

The main types of stem cell transplants and other options are discussed below.

Autologous transplant. This is also called an AUTO transplant or high-dose chemotherapy with autologous stem cell rescue.

In an AUTO transplant, you get your own stem cells after doctors treat the cancer. First, your health care team collects stem cells from your blood and freezes them. Next, you have powerful chemotherapy, and rarely, radiation therapy. Then, your health care team thaws your frozen stem cells. They put them back in your blood through a tube placed in a vein (IV).

It takes about 24 hours for your stem cells to reach the bone marrow. Then they start to grow, multiply, and help the marrow make healthy blood cells again.

Allogeneic transplantation. This is also called an ALLO transplant. In an ALLO transplant, you get another person’s stem cells. It is important to find someone whose bone marrow matches yours. This is because you have certain proteins on your white blood cells called human leukocyte antigens (HLA). The best donor has HLA proteins as much like yours as possible.

Matching proteins make a serious condition called graft-versus-host disease (GVHD) less likely. In GVHD, healthy cells from the transplant attack your cells. A brother or sister may be the best match. But another family member or volunteer may also work.

Once you find a donor, you receive chemotherapy with or without radiation therapy. Next, you get the other person’s stem cells through a tube placed in a vein (IV). The cells in an ALLO transplant are not typically frozen. This way, your doctor can give you the cells as soon as possible after chemotherapy or radiation therapy.

There are 2 types of ALLO transplants. The best type for each person depends on his or her age, health, and the type of disease being treated.

  • Ablative, which uses high-dose chemotherapy

  • Reduced intensity, which uses milder doses of chemotherapy

If your health care team cannot find a matched adult donor, there are other options. Research is ongoing to determine which type of transplant will work best for different people.

  • Umbilical cord blood transplant. This may be an option if you cannot find a donor match. Cancer centers around the world use cord blood.

  • Parent-child transplant and haplotype mismatched transplant. These types of transplants are being used more often. The match is 50%, instead of near 100%. Your donor might be a parent, child, brother, or sister.

Choosing a transplant

Your doctor will recommend an AUTO or ALLO transplant based mostly on the disease you have. Other factors include the health of your bone marrow and your age and general health. For example, if you have cancer or other disease in your bone marrow, you will probably have an ALLO transplant. In this situation, doctors do not recommend using your own stem cells.

Choosing a transplant is complicated. You will need help from a doctor who specializes in transplants. You might need to travel to a center that does many stem cell transplants. Your donor might also need to go. At the center, you will talk with a transplant specialist and have an examination and medical tests.

Before a transplant, you should also think about non-medical factors. These include:

  • Who can care for you during treatment

  • How long you will be away from work and family responsibilities

  • If your insurance pays for the transplant

  • Who can take you to transplant appointments

Your health care team can help you find answers to these questions.

How a transplant works

The information below tells you the main parts of AUTO and ALLO transplants. Your health care team usually does the steps in order. But sometimes certain steps happen in advance, such as collecting stem cells. Ask your health care team what to expect before, during, and after a transplant.

AUTO transplant timeline

Part 1: Collecting your stem cells

During this part, you get injections of a medication to raise your number of stem cells. Your doctor may collect stem cells through your veins using standard IVs or a catheter, which is placed in a large vein in the chest. This stays in place throughout your stay at the hospital. The catheter is used to give chemotherapy, other medications, and blood transfusions.

Time: Several days

Where it is done: Clinic or hospital building. You do not need to stay in the hospital overnight.

Part 2: Transplant treatment

You get high doses of chemotherapy, and rarely, radiation therapy.

Time: 5 to 10 days

Where it is done: A clinic or hospital. At many transplant centers, people need to stay in the hospital for the duration of the transplant, usually about 3 weeks. At some centers, a person receives treatment in the clinic and can come in every day.

Part 3: Getting your stem cells back

This part is called the stem cell infusion. Your health care team puts your stem cells back in your blood through the transplant catheter.

Time: Each infusion usually takes less than 30 minutes. You may receive more than 1 infusion.

Where it is done: A clinic or hospital.

Part 4: Recovery

You take antibiotics and other drugs. You get blood transfusions through your transplant catheter, if needed. This is also when your health care team helps with any transplant side effects.

Time: Approximately 2 weeks

Where it is done: A clinic or hospital. You might be staying in the hospital.

ALLO transplant timeline

Part 1: Collecting stem cells from your donor

During this part, the health care team gives your donor injections of a medication to increase white cells in the blood, if the cells are collected from blood. Some donors will donate bone marrow in the operating room during a procedure which takes several hours.

Time: Varies based on how the stem cells are collected

Where it is done: A clinic or hospital

Part 2: Transplant treatment

You get chemotherapy with or without radiation therapy.

Time: 5 to 7 days

Where it is done: Many ALLO transplants are done in the hospital.

Part 3: Getting the donor cells

This part is called the stem cell infusion. Your health care team puts the donor’s stem cells in your blood through the transplant catheter. It takes less than 1 hour. The transplant catheter stays in until after treatment.

Time: 1 day

Where it is done: A clinic or hospital

Part 4: Recovery

During the recovery, you receive antibiotics and other drugs. This includes medications to prevent graft-versus-host disease. If needed, you get blood transfusions through your catheter. This is also when your health care team takes care of any side effects from the transplant.

After the transplant, people visit the clinic frequently at first and less often over time.

Time: It varies. For an ablative transplant, people are usually in the hospital for about 4 weeks in total. For a reduced intensity transplant, people are in the hospital or visit the clinic daily for about a week.

Milestones of successful transplant

The words “successful transplant” might mean different things to you, your family, and your health care team. Below are 2 ways to measure transplant success:

Your blood counts are back to safe levels. A blood count is the number of red cells, white cells, and platelets in your blood. A transplant makes these numbers very low for 1 to 2 weeks. This causes risks of:

  • Infection from low numbers of white cells, which fight infections

  • Bleeding from low numbers of platelets, which stop bleeding

  • Tiredness from low numbers of red cells, which carry oxygen

Doctors lower these risks by giving blood and platelet transfusions after a transplant. You also take antibiotics to help prevent infections. When the new stem cells multiply, they make more blood cells. Then your blood counts improve. This is one way to know if a transplant is a success.

It controls your cancer. Doctors do stem cell transplants with the goal of curing disease. A cure may be possible for some cancers, such as some types of leukemia and lymphoma. For other people, remission is the best result. Remission is having no signs or symptoms of cancer. After a transplant, you need to see your doctor and have tests to watch for any signs of cancer or complications from the transplant.

Questions to ask the health care team

Talking often with your health care team is important. It gives you information to make decisions about your treatment and care. The following questions may help you learn more about stem cell transplant:

  • Which type of stem cell transplant would you recommend? Why?

  • If I will have an ALLO transplant, how will we find a donor? What is the chance of a good match?

  • What type of treatment will I have before the transplant? Will radiation therapy be used?

  • How long will my treatment take? How long will I stay in the hospital?

  • How will a transplant affect my life? Can I work? Can I exercise and do regular activities?

  • How will we know if the transplant works?

  • What if the transplant does not work? What if the cancer comes back?

  • What are the short-term side effects that may happen during treatment or shortly after?

  • What are the long-term side effects that may happen years later?

  • What tests will I need later? How often will I need them?

  • If I am worried about managing the costs of treatment, who can help me with these concerns?

Related Resources

Side Effects of a Bone Marrow Transplant (Stem Cell Transplant)

Bone Marrow Aspiration and Biopsy

Donating Bone Marrow is Easy and Important: Here's Why

How Umbilical Cord Blood Can Save Someone's Life

Bone Marrow Transplants and Older Adults: 3 Important Questions

More Information

Be the Match: About Transplant

Be the Match: National Marrow Donor Program

Blood & Marrow Transplant Information Network (BMT InfoNet)

National Bone Marrow Transplant Link (nbmtLINK)

U.S. Department of Health and Human Services: Learn About Transplant as a Treatment Option