If you've tried other treatments for acute myeloid leukemia (AML) and there's a chance your cancer may come back, your doctor may suggest a stem cell transplant. It's a powerful treatment that replaces cancer cells with "stem" cells -- immature blood cells that can grow into healthy ones.
It's not an option for everyone. The treatment takes several months and may have side effects and risks, so you'll want to learn about the pros and cons to see if it's a good choice for you.
Types of Stem Cell Transplants
Stem cells are found in your bone marrow -- the spongy center of bones where blood cells are made. They grow into different kinds of blood cells that your body needs. A stem cell transplant can help replace cells in bone marrow that have been damaged by cancer or by the chemotherapy or radiation you had to treat your AML.
In a stem cell transplant, your doctor injects new stem cells into your blood, where they travel to your bone marrow. There they help rebuild your immune system -- your body's defense against disease -- after it's been weakened from chemotherapy.
There are two main types of stem cell transplants: autologous and allogenic.
Autologous stem cell transplant. Your doctor will use your own stem cells in this procedure. They'll take them from your body before you begin cancer treatment, store them, and then put them back into your body after the cancer cells have been killed by chemotherapy.
Why your doctor might suggest it. The new stem cells will not try to attack your body. That helps lower the chance that you could have a serious side effect called "graft-versus-host disease."
Why your doctor might not suggest it. Your stem cells will not be helpful in killing any leftover cancer cells, because they won't see them as a danger. It's also possible that a few cancer cells can be collected with the stem cells and could end up back in your body.
Allogenic stem cell transplant. This kind of transplant uses stem cells donated from another person. Doctors try to find someone whose blood and tissues are similar to yours, so that your body will not see the cells as a threat. Your siblings can often give you the closest match. If you don't have a relative who can donate, you can be matched through a national registry with an anonymous donor.
Why your doctor might suggest it. It's an option if your doctor wants to use the transplant in part to kill any remaining cancer cells. Because allogenic stem cells don't come from your body, they may recognize the cancer as foreign and go after it. Another advantage is that if you need more cells down the road, your doctor can get more from the donor.
Why your doctor might not suggest it. It's possible your body will destroy the stem cells before they have a chance to reach your bone marrow and multiply. There is also a small chance that the donor stem cells could bring with them an infection from the donor. And there's a possibility that the new cells, because they are not from you, attack parts of your body, causing graft-versus-host disease.
What to Expect During a Stem Cell Transplant
The first step is "conditioning," which can take 1 to 2 weeks. During this time, you'll get high doses of chemotherapy or radiation. There are three goals: Kill your cancer cells, make space in your bone marrow for the transplanted cells, and weaken your immune system so it's less likely to attack the new cells.
The high chemo doses can make it an intense part of your treatment. You might get side effects like hair loss, nausea and vomiting, mouth sores, and breathing problems. Your doctor can suggest medicine to ease these problems.
On the day of the infusion, your doctor will give you the stem cells through a tube that they insert into a vein in your chest. You can be awake while this is going on. It won't hurt. Some people say they have a funny taste in their mouth from the chemical that's used to preserve the stem cells if they have been frozen.
You might get a few side effects that should go away quickly, such as:
- Fever or chills
- Feeling short of breath
- Having chest tightness or pain
- Low blood pressure
- Producing less urine
- Feeling weak
What Happens After the Transplant
It will take several weeks for the stem cells to begin making new blood cells in your body. Your medical team will monitor your blood count.
You have a risk of problems like:
Infection. Because your immune system is weak from your conditioning treatment, it may have trouble fighting off infections. Your doctor may give you antibiotics, antiviral drugs, or antifungal medicine to keep you healthy.
Bruising or bleeding. The conditioning treatment also destroys many of your platelets, which are the cells that help your blood clot. So, you might bruise or bleed easily during this time. Your doctor will watch your platelet count, and if it drops dangerously low, you may need to be given extra platelets.
Lung problems. You have a greater chance of getting pneumonia, either from infections or as a side effect of radiation or chemotherapy. Your medical team will watch for this, but make sure to tell them if you have shortness of breath or a hard time breathing.
Graft-versus-host disease (GVHD). Your chances of getting this go up if your stem cells came from a donor. Up to half of people who get an allogenic transplant will get GVHD. This is when the donated stem cells attack the recipient’s body. The first symptom is often a rash or burning sensation in the skin. You can treat it with steroid creams that you put on top of your skin or other medications if it becomes more severe.
Stem cell transplants are complex procedures that come with significant risks, but they can also be an effective treatment for AML. Talk to your doctor about whether it's a good choice for you and what to expect if you have one.