Stem Cell Transplants


What is a stem cell transplant?

Healthcare providers use stem cell transplants to treat people who have life-threatening cancer or blood diseases caused by abnormal blood cells. A stem cell transplant helps your body replace those blood cells with healthy or normal blood cells. If you receive a stem cell transplant, your provider may use your own healthy stem cells or donor stem cells.

Your blood cells come from stem cells in your bone marrow. Your bone marrow constantly creates new stem cells that become blood cells. Stem cell transplants can involve stem cells taken from bone marrow or from blood. Providers sometimes refer to stem cell and bone marrow transplants as haematopoietic stem cell transplants (HSCT). This article focuses on stem cells taken from blood.

What are stem cells used for?

Healthcare providers use stem cells to replace unhealthy blood cells that cause conditions such as several types of leukemia, lymphoma and testicular cancer. They also use transplanted stem cells to treat several types of anemia. Some people who have multiple sclerosis may benefit by receiving healthy stem cells. Researchers are investigating ways to treat other autoimmune diseases with stem cell transplants.

Who is a candidate for a stem cell transplant?

Healthcare providers typically use stem cell transplants to treat life-threatening cancer or blood diseases. Unfortunately, not everyone who has those conditions can have the procedure. Here are factors providers take into consideration:

  • Your general health and medical condition. For example, people who have stem cell transplants go through intensive chemotherapy before treatment. This is conditioning. Providers will evaluate whether you’re able to manage conditioning side effects. They’ll also consider whether you’ll be able to manage stem cell transplant side effects.
  • Your medical condition. Not all cancer or blood diseases respond to stem cell transplants.
  • Your previous treatments. Some medical treatments may affect successful transplants.
  • The healthy stem cells’ source. Providers check whether they can transplant your own healthy stem cells. If not, they’ll search for donors who have stem cells that match your stem cells. That search starts with immediate family members. They may check stem cell registries, internet databases that allow providers to look for matching stem cells donated by the public. If they can’t find enough donated cells, they can’t use a stem cell transplant to treat your condition.

Are stem cell transplants common?

Recently data reported nearly 23,000 people had stem cell transplants in 2018.

Procedure Details

How does stem cell transplantation work?

To understand how stem cell transplants work, it may help to know more about stem cells and their role in your body:

  • Stem cells are young or immature blood cells that your bone marrow produces. Your bone marrow is the soft spongy center of your bone.
  • These stem cells develop into all types of blood cells including white blood cells that protect your body from infection, red blood cells that carry oxygen throughout your body and platelets, which help your blood clot. Stem cells are constantly producing new blood cells to replace damaged, aging or worn-out blood cells.
  • Some cancers and blood diseases happen when your stem cells can’t produce enough healthy blood cells.
  • When this happens, healthcare providers may use chemotherapy or other treatments to destroy unhealthy stem cells. If those treatments aren’t effective, healthcare providers may recommend a stem cell transplant.
  • Stem cell transplants replace unhealthy stem cells with healthy stem cells that can make new healthy blood cells.

Where do stem cells used in HSCT come from?

Healthcare providers obtain stem cells from several sources:

  • People may be able to use their own healthy stem cells to replace unhealthy stem cells. This is an autologous stem cell transplant.
  • Donor stem cells: Some people are able to use donated stem cells that match their stem cells. This is an allogeneic stem cell transplant. If someone has an identical twin, that twin can donate stem cells. This is a syngeneic stem cell transplant.

What happens before a stem cell transplantation?

If you’re a candidate for a stem cell transplant, your healthcare provider will perform the following tests to confirm you’re physically able to manage transplantation processes, including pre-treatment chemotherapy called conditioning and transplantation side effects:

Before your blood tests, your provider may place a central venous catheter (CVC) in one of the large veins in your upper chest. CVCs are tubes that serve as central lines that providers use to take blood and provide medication and fluids. CVCs eliminate repeated needle sticks to draw blood or insert intravenous tubes throughout the transplantation process.

What is transplant conditioning?

Transplant conditioning is intensive chemotherapy and/or radiation therapy that kills cancer cells in your bone marrow. Conditioning also kills existing blood cells.

What else happens before a stem cell transplant?

If you’re receiving your own stem cells, your provider may give you medication to boost your stem cell production. They’ll do follow-up blood tests to check on stem cell production.

What happens during a stem cell transplant?

If you’re receiving your own stem cells, your providers will take blood so they can remove healthy stem cells for transplant. . To do that, they connect veins in both of your arms to a cell separator machine. The machine pulls your blood from one arm, filters the blood and then returns it to through your other arm. This process doesn’t hurt. Providers may need to take blood more than once to ensure they have enough stem cells to transplant. The actual transplantation involves receiving your stem cells via your CVC.

What happens if I’m receiving donated cells?

Just like someone receiving their own cells, you’ll receive healthy stem cells via your CVC.

What happens after a stem cell transplant?

Your new stem cells will need time to produce new blood cells. If you received donor stem cells, your transplanted stem cells will replace unhealthy stem cells and begin to build a new immune system. This process is engraftment.

Either way, you may need to stay in or close to the hospital for several months so your healthcare providers can support your recovery and monitor your progress. Here’s what you can expect after your stem cell transplant:

  • Pre-treatment chemotherapy affects your immune system’s ability to protect you from infections. To reduce that risk, you’ll be alone in a carefully cleaned room with very limited physical contact with other people.
  • Some people have nausea, vomiting and diarrhea after their transplant. Your providers will give you medication to ease those symptoms and fluids to replace what you lost.
  • If you received donor cells, you’ll receive immunosuppressant medication to reduce the chance your body will reject the donor cells.
  • You may need blood transfusions to replace red blood cells and platelets.

Risks / Benefits

What are HSCT advantages?

Successful stem cell transplants may help people when previous treatments don’t slow or eliminate certain cancers.

What are common stem cell transplant complications?

The greatest risk is that you’ll go through the procedure and your transplanted stem cells can’t slow or eliminate your illness.

Allogeneic and autologous stem cell transplants have different complications. Allogeneic stem cell transplants can result in graft versus host disease. This happens when your immune system attacks new stem cells. Potential complications will vary based on your overall health, age and previous treatment. If you’re considering a stem cell transplant, your healthcare provider will outline potential complications so you can weigh those risks against potential benefits.

Recovery and Outlook

How long does it take to recover from a stem cell transplant?

It can take several weeks to several months to recover from a stem cell transplant. Your healthcare provider may recommend you stay in or near the hospital or transplant center for the first 100 days after your procedure.

What is the success rate for stem cell transplants?

It’s difficult to calculate an overall success rate. That said, the most recent data show the highest number of stem cell transplants involved people with multiple myeloma or Hodgkin and non-Hodgkin lymphoma who received autologous stem cell transplants. Here is information on three-year survival rates:

  • Multiple myeloma: Data show 79% were alive three years after transplant.
  • Hodgkin lymphoma: Studies show most people receive HSCT to treat Hodgkin lymphoma that came back after chemotherapy. Of those, 92% of those people were alive three years after the transplant.
  • Non-Hodgkin lymphoma: Like Hodgkin lymphoma, most people receive HSCT for NHL that’s come back. Of those, 72% were alive three years after diagnosis.

When to Call the Doctor

A successful stem cell transplant can change your life, curing your condition or slowing its growth. But it’s not an overnight transformation. It can take a year or more for you to recover. Here are some challenges and ways to overcome them:

You may have days when you feel exhausted and days when you feel fine. A hard day doesn’t mean you’re not doing well. It means you need to give yourself a break and take it easy.

  • You may find yourself on an emotional rollercoaster. You may feel confident and optimistic about your healthy future and then worried about your condition coming back. Studies show regular, appropriate exercise may help to ease your anxiety along with boosting your immune system. Talk to your healthcare provider about exercise programs that may make sense for you.
  • Your immune system won’t be as strong as it was before. Your provider will have tips for avoiding infection and coping if you get sick. Ask your provider about healthy eating habits and other things you can do to boost and protect your immune system.

Additional Details

When should I see my healthcare provider after my stem cell transplant?

You’ll have regular follow-up appointments with your provider. But it’s important to remember your immune system likely will be weak for a year or so after your transplantation. Contact your provider right away if you develop any of the following symptoms:

A note from Cleveland Clinic

If you’ve been coping with cancer or a blood disease, a stem cell transplant can be a new lease on life. It can mean hope for a cure or remission when other treatments haven’t worked. But stem cell transplants come with demanding physical challenges and significant risks. Not everyone who has cancer or blood conditions is a candidate for a stem cell transplant. Unfortunately, not everyone who is a candidate but needs donor stem cells finds a donor. If you’re considering a stem cell transplant, talk to your healthcare provider about potential risks and benefits. They’ll evaluate your situation, your options and potential outcomes.

Last reviewed by a Cleveland Clinic medical professional on 03/14/2022.


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