Autologous Stem Cell Transplant or Bone Marrow Transplant
What is bone marrow?
Bone marrow is a spongy material found inside our large bones, like the femur (thigh), hip, and ribs. Bone marrow is made up of cells called hematopoietic stem cells. Hematopoietic cells are given (transplanted) to you during a stem cell transplant. (NOTE: These stem cells are different than those used for research - those are embryonic stem cells).
Hematopoietic stem cells are "baby" cells that become white blood cells, red blood cells, or platelets. They can be called blood-forming stem cells. They grow and are stored in the bone marrow until they are needed. Each type of cell has a job:
- White blood cells (leukocytes): Cells that help fight infection.
- Red blood cells (erythrocytes): Carry oxygen from the lungs to the rest of the body and return carbon dioxide to the lungs as waste.
- Platelets (thrombocytes): Help the body form blood clots to control bleeding.
What does autologous mean?
Autologous means that the transplanted cells come from your own body. For example, if Jack is having an autologous stem cell transplant, the stem cells come from Jack himself. Many people think a transplant must be something taken from a donor (another person), but that would be called an allogeneic transplant. In an autologous transplant, Jack the patient "donates" his cells to himself.
What types of cancer is this therapy used for?
Autologous transplants (called “auto transplant” for short) are used to treat a number of different cancers, such as leukemias, myelodysplastic syndrome, multiple myeloma, Hodgkin's disease, non-Hodgkin’s lymphoma, testicular cancer and neuroblastoma, among others.
How do we collect these cells?
When providers first started doing these transplants, the only way to get stem cells was directly from the bone marrow. This is where the term bone marrow transplant comes from. In the past, the cells would be collected in the operating room by inserting needles into your hip bones to remove the bone marrow. Stem cells were removed from the marrow and preserved in dimethyl sulfoxide (DMSO) and frozen until needed.
In recent years, providers found that giving a medication called granulocyte colony-stimulating factor, or GCSF, stimulates (revs up) your stem cells to be released from the bone marrow and into the bloodstream. Using a blood test, they can tell how many cells are in your bloodstream. Once the number is high enough, you will go to the pheresis department at the hospital to have the cells removed. This procedure is called "apheresis.” With apheresis, there is no longer a need to remove stem cells from bone marrow in the OR.
- Your cells are removed using a catheter in the chest wall, or with 2 large intravenous (IV) catheters, one placed in each arm.
- Blood is taken out, run through the pheresis machine to remove the stem cells, and the rest of your blood is returned to you.
- The cells are frozen in the same DMSO preservative that is used for bone marrow. Preserving the cells on ice, called “cryopreservation,” is needed because the cells must be removed (“harvested”) months before your actual transplant.
- During the collection, you may have tingling or numbness around your lips. This is caused by a loss of calcium and often gets better by eating some calcium tablets.
What do we mean by "transplant"?
To understand the stem cell transplant, you need to know about chemotherapy. Chemotherapy is a group of medications that work by killing rapidly dividing cells in the body. Cancer cells tend to divide quickly, but so do many healthy cells (like cells in the gastrointestinal tract, hair follicles, and blood cells). If you bite the inside of your lip, there is a good chance the spot will be healed by the next day. This is because those cells divide rapidly.
Chemotherapy can damage your healthy cells, leading to side effects. For instance, if a patient has diarrhea from a medication, the provider may decide to decrease the dose. This is called "dose-limiting toxicity." One important dose-limiting toxicity is low blood counts (low white blood cells, red blood cells, and platelets).
With an autologous transplant, providers give you high doses of chemotherapy to wipe out your bone marrow, but then later "rescue" the bone marrow using your own stem cells (which were collected earlier, before chemotherapy).
How is the transplant done?
You get high doses of chemotherapy to try to kill any cancer cells in your body. You will then rest for 1 or 2 days to let your body process and clear out the chemotherapy, so the new cells are not damaged.
- On the day of the "transplant,” you are given some medications (called premedications) to prevent any reactions to the DMSO preservative.
- You will also receive intravenous (IV) fluids.
- Your blood pressure and heart rate are closely watched. Once you have received the premedications, the frozen stem cells are thawed. They are given back to you like a blood transfusion. They are given through your intravenous line.
After infusing the stem cells, where do they go?
They find their way back to the bone marrow space and get to work. Remember, when the stem cells arrive in the bone marrow, things are in bad shape - almost all the old marrow cells have been killed ("ablated") by the chemo. The stem cells start making new white and red blood cells and platelets. It can take anywhere from 7 to 14 days for the stem cells to make new cells, and for those new cells to mature enough to work the way they should.
What happens while we wait?
This waiting period, also called the "nadir," is often the hardest part. The blood cell counts are very low, putting you at risk for infections, bleeding, and severe fatigue. You do not have any white blood cells to fight infections, so you may have fevers and need antibiotics. All visitors and healthcare staff must wash their hands before entering your room. Anyone who is sick or lives with someone who is sick should stay home.
Low platelet counts can lead to bleeding, and platelet transfusions are common during this time. A low red blood cell count (called anemia) can also be hard. You may look pale, feel very tired, and need red blood cell transfusions. Many patients say the worst side effect is extreme fatigue. Just getting out of bed is a chore. When able, short walks in the halls or light exercise in your room can increase your energy.
You must also deal with the side effects of the chemotherapy you received. These include diarrhea, nausea and/or vomiting, hair loss, fever, chills, decreased appetite, and mouth sores (called mucositis). Every patient is different, and it is hard to tell who will have more side effects. The chemotherapy drugs used before the transplant can vary, and some medications are more likely to cause certain side effects than others.
What can a friend or family member do to help me during this time?
Friends and family should be supportive, letting you rest when needed, and understand that you may not feel like eating much during this time. Make one family member the contact person for friends and family. You can tell this contact person how you are feeling each day and whether you would like visitors or phone calls. They should respect your wishes. Send a supportive note or a card. If you have children, knowing that friends or family are taking care of things like carpooling and school homework can be very helpful. Depending on the protocol for the transplant, you may be spending this time in the hospital, at an apartment near the cancer center, or at home.
What is engraftment?
Engraftment is the point when the stem cells start doing their job and blood cell counts start to come up.
- The first number we look for is the neutrophil count, which is the type of white blood cell that is most important in fighting infection. The care team will watch your neutrophil count and when it reaches a specific level, you can stop antibiotics and, in many cases, can go home. The time until engraftment varies but is often between 7-12 days.
- The red blood cell and platelet counts can take a few weeks to get back to a normal range, but you can often go home once you are not regularly needing blood or platelet transfusions.
How will I feel once I am home?
This can vary greatly, depending on what has happened over the past few weeks. It can take people weeks, months, or even a year to feel like their "old self" again. Some patients report having no appetite, or food tasting like metal, for months after the transplant. This can be a hard time, as family and friends may assume that the person is "better" since they are home, and the transplant is over. They may expect you to be back at work, to return to school, or to run a household. You should resume normal activities slowly and add on jobs or duties every couple of days.
Resources for More Information
Blood Forming Stem Cell Transplants from the NCI
What is a Stem Cell Transplant from ASCO
Abeloff M, Niederhuber JE, Armitage JO, Doroshow, JH, Kastan MB, Tepper, JE. Abeloff’s Clinical Oncology. 5th edition. Philadelphia: Churchill Livingstone; 2014.