Understanding Bone Marrow and Stem Cell Transplants

Stem cell transplants from bone marrow and other sources offer lifesaving treatment. They are also taxing physically and emotionally.

It’s important to know:

  • A transplant may enable doctors to destroy blood diseases and improve your body’s ability to produce healthy new blood cells.
  • A transplant may use your cells or cells from a donor.
  • Transplants have the highest chance of success when a donor’s cells closely match yours.
  • Transplant patients must devote weeks to treatment, with close monitoring.
  • Your care team will carefully consider the risks and benefits of a transplant and discuss them with you.

What is bone marrow?

Bone marrow is the soft, spongy material inside bones. It contains cells called blood-forming stem cells (hematopoietic cells). Stem cells divide and multiply. Some mature into one of three blood cell types:

  • White blood cells that fight infection
  • Red blood cells that carry oxygen throughout the body
  • Platelets that help the blood clot

Stem cells are found in bone marrow, in the bloodstream and in umbilical cord blood. In the bloodstream, they are called peripheral blood stem cells (PBSCs). Stem cells from any of these sources can be used in transplants.

Medical Illustration of stem cell transplant with donor cells
OHSU is the only center in Oregon with the expertise to offer stem cell transplants with donor cells. Click image to enlarge.

What are stem cell transplants?

With a stem cell transplant, a doctor gives you healthy new cells that help you fight infection and disease. Doctors most often use bone marrow transplants to treat blood disorders and blood cancers that:

  • Cause your bone marrow to make abnormal cells.
  • Slow down cell production.

A transplant is like a blood transfusion. There are three types:

  • Bone marrow transplant: Doctors collect stem cells from marrow with a hollow needle.
  • Peripheral blood stem cell transplant: PBSCs are collected from blood drawn with a small needle.
  • Hematopoietic stem cell transplant: Stem cells are collected from umbilical cord blood.

How stem cell transplants work

Conditioning: After stem cells are collected and preserved, you begin a process called conditioning. In some cases, the patient receives high doses of chemotherapy, whole body radiation therapy or both. In other cases, lower doses are used. The process destroys cancer cells and healthy cells that could keep your body from accepting transplanted cells. This weakens the immune system, making it more likely to accept the transplanted cells.

Transplant: New bone marrow cells are placed in your bloodstream with an IV. The cells collect in your bone marrow, where they begin to produce new blood cells after a few weeks.

Recovery: You’ll stay in our state-of-the-art transplant facility for close monitoring for two to three weeks. The unit has HEPA filtration to reduce germs and the risk of infection. Monitoring is essential because your immune system will be weak, and infections are common. In some cases, patients can stay nearby instead of at the hospital.

Who gets a transplant?

At the OHSU Knight Cancer Institute, we consider every person with blood cancer for bone marrow/stem cell transplant. It might be right for you if your cancer didn’t respond to other treatment or if your cancer came back after treatment. Our providers meet at weekly gatherings called tumor boards to develop the best treatment options for each patient.

Our team considers factors such as your:

  • Needs and wishes
  • Age and health history
  • Disease type and severity

You’ll want to consider:

  • Financial implications
  • Health risks
  • Time off work
  • The need to be near OHSU for weeks
  • Physical and emotional difficulties that come with having a transplant

What disorders do transplants treat?

Bone marrow/stem cell transplants may be an option to treat:


  • Acute lymphoblastic leukemia
  • Acute myelogenous leukemia
  • Chronic myeloid leukemia
  • Chronic lymphocytic leukemia


  • Hodgkin lymphoma
  • Non-Hodgkin lymphoma
  • Waldenstrom macroglobulinemia

Other blood cancers:

Other blood cancers and blood disorders:

Other conditions:

Types of stem cell transplants

There are two main types of transplants, each with risks and benefits. OHSU is the only place in Oregon that offers allogeneic transplants.

Autologous transplant

What is it? This type uses your own stem cells. This eliminates the risk of your body rejecting donor cells or of donor cells attacking your body. A relapse may be more likely, though, because you won’t have healthy donated cells to attack any diseased cells that remain after conditioning.

How it works: Your care team collects bone marrow using a hollow needle or draws blood and uses a machine to separate out stem cells. The stem cells are frozen. After the conditioning process, the cells are transplanted using a slow IV drip. 

Allogeneic transplant

What is it? We use cells from a donor. Sometimes your own cells are too diseased to collect and reuse. Donor cells are more aggressive in killing any diseased cells left after conditioning. The risk is that they may aggressively target your healthy cells as well.

How it works: After the conditioning process, we transplant healthy donor cells using a slow IV drip. The donor cells help your body rebuild your immune system. A donor can be a relative or someone else whose marrow matches yours.

Allogeneic transplants include:

  • Syngeneic transplants that use cells from a twin.
  • Haploidentical transplants that use partial or imperfectly matched cells. OHSU is among the few hospitals in the country with the expertise to offer these.
  • Cord blood transplants that use cells from umbilical cord blood collected and stored right after delivery.

Bone marrow donors

OHSU has participated in Be The Match: The National Marrow Donor Program since 1996. This program helps people find a lifesaving marrow or PBSC donor. Donors must meet medical guidelines and should expect to spend 20 to 30 hours in treatment over four to six weeks.

Testing: To find the closest match, doctors will test your blood and a potential donor’s blood to find their human leukocyte antigen (HLA) type.

HLA markers: Everyone inherits a set of HLA markers from their parents. These markers, contained in almost all of your cells, tell your body which cells belong to you. The more matching markers you and a donor have, the better your chances of a successful transplant. OHSU has success with haploidentical transplants, however, in which as few as half the markers match. 

What to expect

  1. First appointments: We discuss whether you might benefit from a transplant, then begin the process of getting insurance authorization.
  2. Evaluation: You have testing that helps us better understand if a transplant will work.
  3. Conditioning: You receive chemotherapy and/or radiation therapy to kill cancer cells and bone marrow cells.
  4. Transplant: We transplant the cells, and they begin to multiply in your bone marrow.
  5. Recovery and rehabilitation: Your care team will closely monitor you, usually in the hospital, for two to three weeks as you wait for your new cells to begin producing healthy blood cells. 

Transplant risks

As with any procedure, transplants involve risks. Your care team will discuss these with you in detail.

Infection: Chemotherapy and radiation therapy weaken your immune system. You are at high risk of infection for up to six weeks until your new cells make healthy blood cells. Your care team will keep you in a safe environment where airborne germs are contained. You will receive safety instructions for going home.

Low platelets: Your platelets will be low for three or more weeks. We will take great care to help you avoid injury or bleeding. Some patients may need a blood transfusion to replace platelets.

Pain: Mouth or throat pain is a common side effect of chemotherapy and radiation therapy. It may cause difficulty eating or swallowing for a few weeks.

Graft failure: Transplant (graft) failure occurs when the body rejects the donor cells. This is rare with stem cell transplants but more common when HLA types are poorly matched.

Graft versus host disease: This happens when transplanted cells from the donor attack the recipient’s tissue and organs. This common complication can range from mild to life-threatening.

Organ damage: Chemotherapy and radiation can leave lasting damage. We’ll monitor you closely for signs.

Infertility: The chemotherapy and radiation therapy used before transplants typically result in infertility. OHSU fertility experts can offer options to preserve your ability to have children before treatment begins.

Physical and emotional effects

Transplants are difficult. They require weeks in or near the hospital, away from work and regular activities. Our cancer social workers can provide support to you and your family before, during and after treatment:

  • Mental health and emotional issues: These day-to-day concerns often accompany a transplant. We can help you and your family identify counselors, support groups and resources to cope.
  • Resource and financial concerns: Our social workers will connect you with financial counselors, housing counselors and other services to make the process as seamless as possible.
  • Side effects: Our Bone Marrow Transplant Survivorship Program can work with you and your primary care doctor to manage side effects and other concerns after a transplant.

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