High-dose Chemotherapy and Stem Cell Transplant for Ewing Tumors
This type of treatment is being studied for patients with Ewing tumors that are hard to cure with other treatments, such as those with metastatic disease or with Ewing tumors that come back after the standard treatment.
The doses of chemotherapy (chemo) drugs that can be given safely are normally limited by the side effects these drugs can cause. One of the most serious is damage to the bone marrow, which is where new blood cells are made. Even though higher doses of these drugs might be more effective in treating Ewing tumors, they can’t be given because they would severely damage bone marrow cells, leading to life-threatening shortages of blood cells.
To try to get around this problem, a doctor may treat the child with high-dose chemo (sometimes along with radiation therapy) and then use a stem cell transplant to “rescue” the bone marrow, giving the child new blood stem cells to replace those that were destroyed.
In the past, this type of treatment was often called a bone marrow transplant.
If a stem cell transplant is considered as part of the initial treatment plan for a Ewing tumor, the patient first gets standard doses of chemo, then local treatment of the tumor (surgery and/or radiation therapy), followed by high-dose chemo and a stem cell transplant.
What happens in a stem cell transplant
The first step in a stem cell transplant is to collect, or harvest, the child’s own blood-producing stem cells to use later. (These are the cells that make the different types of blood cells.) This type of transplant, where the stem cells are taken from the patient (as opposed to coming from someone else), is known as an autologous transplant.
In the past, the stem cells were often collected from the child’s bone marrow, which required a minor operation. But doctors have found that these cells can be taken from the bloodstream using a procedure similar to a blood donation. Instead of going into a collecting bag, the blood goes into a special machine that filters out the stem cells and returns the other parts of the blood to the person’s body. The stem cells are then frozen until the transplant. This may need to be done more than once.
Once the stem cells have been frozen and stored, the child gets high-dose chemo, sometimes along with radiation therapy. When the treatment is finished, the patient’s stem cells are thawed and returned to the body in a blood transfusion. The stem cells travel through the bloodstream and settle in the bone marrow. Over the next few weeks, they start to make new, healthy blood cells.
Until this happens, the child is at high risk of infection because of a low white blood cell count, as well as bleeding because of a low blood platelet count. To avoid infection, protective measures are taken, such as using special air filters in the hospital room and having visitors wear protective clothing. Blood and platelet transfusions and treatment with antibiotics may also be used to prevent or treat infections or bleeding problems.
A stem cell transplant is a complex treatment that can cause life-threatening side effects. If the doctors think your child may benefit from a transplant, it should be done at a nationally recognized cancer center where the staff has experience in doing the procedure and managing the recovery period.
A stem cell transplant often requires a long hospital stay and can be very expensive (costing well over $100,000). Some insurance companies might view it as an experimental treatment and may not pay for it. Be sure to get a written approval from your insurer before treatment if this procedure is recommended for your child. Even if the transplant is covered by your insurance, your co-pays or other costs could easily amount to many thousands of dollars. It is important to find out what your insurer will cover before the transplant to get an idea of what you might have to pay.
Possible side effects
The possible side effects from a stem cell transplant are generally divided into early (short-term) and late (long-term) effects.
Early or short-term effects: Possible early complications and side effects are basically those caused by the high-dose chemo (see the Chemotherapy section of this document) and can be severe. They can include:
- Low blood cell counts (with fatigue and increased risks of infection and bleeding)
- Nausea and vomiting
- Loss of appetite
- Mouth sores
- Hair loss
One of the most common short-term effects is an increased risk of serious infections. Antibiotics are often given to try to prevent this. Other side effects, like low red blood cell and platelet counts, might require blood product transfusions or other treatments.
Late and long-term side effects: Some complications and side effects can last for a long time or might not occur until years after the transplant. These can include:
- Radiation damage to the lungs
- Problems with the thyroid or other hormone-making glands
- Problems with fertility
- Cataracts (damage to the lens of the eye that can affect vision)
- Damage to bones or problems with bone growth
- Development of another cancer (including leukemia) years later
Be sure to talk to your child’s doctor before the transplant to learn about possible long-term effects your child might have.
For more on stem cell transplants, see Stem Cell Transplant (Peripheral Blood, Bone Marrow, and Cord Blood Transplants).
Last Medical Review: September 18, 2014 Last Revised: February 4, 2016