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

Approved by the Cancer.Net Editorial Board, 07/2020

A bone marrow transplant is a medical treatment that replaces your bone marrow with healthy cells. The replacement cells can either come from your own body or from a donor.

A bone marrow transplant is also called a stem cell transplant or, more specifically, a hematopoietic stem cell transplant. Transplantation can be used to treat certain types of cancer, such as leukemia, myeloma, and lymphoma, and other blood and immune system diseases that affect the bone marrow.

What are stem cells? What is bone marrow?

Stem cells are special cells that can make copies of themselves and change into the many different kinds of cells that your body needs. There are several kinds of stem cells and they are found in different parts of the body at different times.

Cancer and cancer treatment can damage your hematopoietic stem cells. Hematopoietic stem cells are stem cells that turn into blood cells.

Bone marrow is soft, spongy tissue in the body that contains hematopoietic stem cells. It is found in the center of most bones. Hematopoietic stem cells are also found in the blood that is moving throughout your body.

When hematopoietic stem cells are damaged, they may not become red blood cells, white blood cells, and platelets. These blood cells are very important and each one has a different job:

Red blood cells carry oxygen throughout your body. They also take carbon dioxide to your lungs so that it can be exhaled.

White blood cells are a part of your immune system. They fight pathogens, which are the viruses and bacteria that can make you sick.

Platelets form clots to stop bleeding.

A bone marrow/stem cell transplant is a medical procedure by which healthy stem cells are transplanted into your bone marrow or your blood. This restores your body's ability to create the red blood cells, white blood cells, and platelets it needs.

What are the different types of transplant?

There are different types of bone marrow/stem cell transplants. The 2 main types are:

Autologous transplant. Stem cells for an autologous transplant come from your own body. Sometimes, cancer is treated with a high-dose, intensive chemotherapy or radiation therapy treatment. This type of treatment can damage your stem cells and your immune system. That's why doctors remove, or rescue, your stem cells from your blood or bone marrow before the cancer treatment begins.

After chemotherapy, the stem cells are returned to your body, restoring your immune system and your body's ability to produce blood cells and fight infection. This process is also called an AUTO transplant or stem cell rescue.

Allogenic transplant. Stem cells for an allogenic transplant come from another person, called a donor. The donor's stem cells are given to the patient after the patient has chemotherapy and/or radiation therapy. This is also called an ALLO transplant.

Many people have a “graft-versus-cancer cell effect” during an ALLO transplant. This is when the new stem cells recognize and destroy cancer cells that are still in the body. This is the main way ALLO transplants work to treat the cancer.

Finding a “donor match” is a necessary step for an ALLO transplant. A match is a healthy donor whose blood proteins, called human leukocyte antigens (HLA), closely match yours. This process is called HLA typing. Siblings from the same parents are often the best match, but another family member or an unrelated volunteer can be a match too. If your donor’s proteins closely match yours, you are less likely to get a serious side effect called graft-versus-host disease (GVHD). In this condition, the healthy transplant cells attack your cells.

If your health care team cannot find a donor match, there are other options.

Umbilical cord blood transplant. In this type of transplant, stem cells from umbilical cord blood are used. The umbilical cord connects a fetus to its mother before birth. After birth, the baby does not need it. Cancer centers around the world use cord blood. Learn more about cord blood transplants.

Parent-child transplant and haplotype mismatched transplant. Cells from a parent, child, brother, or sister are not always a perfect match for a patient's HLA type, but they are a 50% match. Doctors are using these types of transplants more often, to expand the use of transplantation as an effective cancer treatment.

How does a bone marrow/stem cell transplant work?

The information below tells you the main steps of AUTO and ALLO transplants. In general, each process includes collecting the replacement stem cells, the patient receiving treatments to prepare their body for the transplant, the actual transplant day, and then the recovery period.

Often, a small tube may be placed in the patient's chest that remains through the transplant process. It is called a catheter. Your health care team can give you chemotherapy, other medications, and blood transfusions through a catheter. A catheter greatly reduces the amount of needles used in the skin, since patients will need regular blood tests and other treatments during a transplant.

Please note that transplants are complex medical procedures and sometimes certain steps may happen in a different order or on a different timetable, to personalize your specific care. Ask your health care whether you will need to be in the hospital for different steps, and if so, how long. Always talk with your health care team about what to expect before, during, and after your transplant.

How does an AUTO transplant work?

Step 1: Collecting your stem cells. This step takes several days. First, you will get injections (shots) of a medication to increase your stem cells. Then your health care team collects the stem cells through a vein in your arm or your chest. The cells will be stored until they are needed.

Step 2: Pre-transplant treatment. This step takes 5 to 10 days. You will get a high dose of chemotherapy. Occasionally, patients also have radiation therapy.

Step 3: Getting your stem cells back. This step is your transplant day. It takes about 30 minutes for each dose of stem cells. This is called an infusion. Your health care team puts the stem cells back into your bloodstream through the catheter. You might have more than one infusion.

Step 4: Recovery. Your doctor will closely monitor your cells' recovery and growth and you will take antibiotics to reduce infection. Your health care team will also treat any side effects. Read more details below about recovering from a bone marrow transplant.

How does an ALLO transplant work?

Step 1: Donor identification. A matched donor must be found before the ALLO transplant process can begin. Your HLA type will be found through blood testing. Then, your health care team will work with you to do HLA testing on potential donors in your family, and if needed, to search a volunteer registry of unrelated donors.

Step 2: Collecting stem cells from your donor. Your health care team will collect cells from either your donor’s blood or bone marrow. If the cells are coming from the bloodstream, your donor will get daily injections (shots) of a medication to increase white cells in their blood for a few days before the collection. Then, the stem cells are collected from their bloodstream. If the cells are coming from bone marrow, your donor has a procedure called a bone marrow harvest in a hospital's operating room.

Step 3: Pre-transplant treatment. This step takes 5 to 7 days. You will get chemotherapy, with or without radiation therapy, to prepare your body to receive the donor's cells.

Step 4: Getting the donor cells. This step is your transplant day. Your health care team puts, or infuses, the donor’s stem cells into your bloodstream through the catheter. Getting the donor cells usually takes less than an hour.

Step 5: Recovery. During your initial recovery, you will get antibiotics to reduce your risk of infection and other drugs, including medications to prevent and/or manage GVHD. Your health care team will also treat any side effects from the transplant. Read more details below about bone marrow transplant recovery.

What is recovering from a bone marrow transplant like?

Recovery from a bone marrow/stem cell transplant takes a long time. Recovery often has stages, starting with intensive medical monitoring after your transplant day. As your long-term recovery moves forward, you will eventually transition to a schedule of regular medical checkups over the coming months and years.

During the initial recovery period, it's important to watch for signs of infection. The intensive chemotherapy treatments that you get before your transplant also damage your immune system. This is so your body can accept the transplant without attacking the stem cells. It takes time for your immune system to work again after the transplant. This means that you are more likely to get an infection right after your transplant.

To reduce your risk of infection, you will get antibiotics and other medications. If you had an ALLO transplant, your medications will include drugs to prevent and/or manage GVHD. Follow your health care team's recommendations for how to prevent infection immediately after your transplant.

It is common to develop an infection after a bone marrow transplant, even if you are very careful. Your doctor will monitor you closely for signs of an infection. You will have regular blood tests and other tests to see how your body and immune system are responding to the donor cells. You may also get blood transfusions through your catheter.

Your health care team will also develop a long-term recovery plan to monitor for late side effects, which can happen many months after your transplant. Learn more about the possible side effects from a bone marrow transplant.

What to consider before a transplant

Your doctor will recommend the best transplant option for you. Your options depend on the specific disease diagnosed, how healthy your bone marrow is, your age, and your general health. For example, if you have cancer or another disease in your bone marrow, you will probably have an ALLO transplant because the replacement stem cells need to come from a healthy donor.

Before your transplant, you might need to travel to a center that does many stem cell transplants. Your doctor may need to go, too. At the center, you will talk with a transplant specialist and have a medical examination and different tests.

A transplant will require a lot of time receiving medical care away from your daily life. It is best to have a family caregiver with you. And, a transplant is an expensive medical process. Talk about these questions with your health care team and your loved ones:

  • Can you describe the role of my family caregiver in taking care of me?

  • How long will I and my caregiver be away from work and family responsibilities?

  • Will I need to stay in the hospital? If so, when and how long?

  • Will my insurance pay for this transplant? What is my coverage for my follow-up care?

  • How long will I need medical tests during my recovery?

How do you know if the transplant worked?

A successful transplant may mean different things to you, your family, and your health care team. Here are 2 ways to know if your transplant worked well.

Your blood counts are back to safe levels. A blood count measures the levels of red blood cells, white blood cells, and platelets in your blood. At first, the transplant makes these numbers very low for 1 to 2 weeks. This affects your immune system and puts you at a risk for infections, bleeding, and tiredness. Your health care team will lower these risks by giving your blood and platelet transfusions. You will also take antibiotics to help prevent infections.

When the new stem cells multiply, they make more blood cells. Then your blood counts will go back up. This is one way to know if a transplant was a success.

Your cancer is controlled. Curing your cancer is often the goal of a bone marrow/stem cell transplant. A cure may be possible for certain cancers, such as some types of leukemia and lymphoma. For other diseases, remission of the cancer is the best possible result. Remission is having no signs or symptoms of cancer.

As discussed above, you need to see your doctor and have tests regularly after a transplant. This is to watch for any signs of cancer or complications from the transplant, as well as to provide care for any side effects you experience. This follow-up care is an important part of your recovery.

Questions to ask the health care team

It is important to talk often with your health care team before, during, and after a transplant. You are encouraged to gather information, ask questions, and work closely with your health care team on decisions about your treatment and care. In addition to the list above, here are some possible questions to ask. Be sure to ask any question that is on your mind.

  • What type of transplant would you recommend? Why?

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

  • What type of treatment will I have before the transplant?

  • How long will my pre-transplant treatment take? Where will this treatment be given?

  • Can you describe what my transplant day will be like?

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

  • What side effects could happen during treatment, or just after?

  • What side effects could happen years later?

  • What tests will I need after the transplant? How often?

  • Who can I talk to if I am worried about the cost?

  • How will we know if the transplant worked?

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

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

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