A bone marrow transplant (BMT) is a treatment for children with certain types of cancer or other diseases. The goal of BMT is to replace a child’s diseased bone marrow with healthy bone marrow.
Bone marrow is the spongy material in the center of the bones that makes all types of blood cells, including young blood cells called stem cells. In BMT, stem cells are filtered, and then put back into the same child. Or they are put into another sick child. These stem cells will grow and become new and healthy bone marrow. Transplanted stem cells are called the graft.
There are different types of BMT depending on how the healthy stem cells are collected.
Your child is his or her own donor. Stem cells can be collected from your child in 2 different ways:
Peripheral blood stem cells (PBSCs). Stem cells are taken from your child by apheresis. Apheresis is a process of collecting stem cells that float in the blood (peripheral blood stem cells). The cells are then given back to your child after intensive treatment.
Bone marrow harvest. Stem cells are collected from your child by a needle placed into the soft center of the bone. Most sites used for bone marrow harvesting are in the hip bones because they have a larger number of stem cells.
The donor is another person who shares the same or similar genetic type as your child. This is often a brother or sister. Finding a matching donor can be a lengthy process. In some cases, a parent may be a donor. Or the donor may be a matched unrelated donor (MUD) found on a bone marrow registry. Stem cells are taken from the donor either by apheresis or bone marrow harvest.
Stem cells are taken from an umbilical cord right after a baby’s birth.
These stem cells grow into mature blood cells quicker and more effectively than stem cells from the bone marrow of another child or adult. The stem cells are tested, typed, counted, and frozen until they are needed for a transplant.
Your child’s transplant is managed by a team of specialists who care for children having BMTs. This team includes:
Doctors. Healthcare providers who specialize in oncology, hematology, immunology, and bone marrow transplantation.
Transplant nurse coordinator. This professional organizes all aspects of care given to your child before and after the transplant. He or she will give you information, and arrange testing and follow-up care.
Social worker. This professional will help your family deal with issues such as lodging and transportation, finances, and legal issues. He or she can also help arrange different ways to help your child continue with schooling.
Dietitian. A provider who will help your child with nutritional needs before and after the transplant.
Physical therapist. A provider who will help your child regain strength after the transplant.
Pastoral care. This includes people trained to give spiritual care and support.
Other team members who may evaluate your child before and after BMT as needed include:
Infectious disease specialist
Child life specialist
The goal of BMT is to cure many diseases and certain types of cancer. It can be used to:
Replace diseased bone marrow with healthy bone marrow. This is done for conditions such as leukemia, aplastic anemia, and sickle cell anemia.
Replace bone marrow after high doses of chemotherapy or radiation are given to treat cancer. This process is often called rescue instead of transplant. This is done for diseases like lymphoma and neuroblastoma.
Replace bone marrow with healthy bone marrow to prevent more damage from a genetic disease. This is done for diseases such as Hurler syndrome and adrenoleukodystrophy disorder.
Diseases that can be treated with BMT include:
Cancers such as leukemia, lymphoma, neuroblastoma, rhabdomyosarcoma, brain tumors, or kidney cancer
Immune deficiency such as severe combined immunodeficiency disorder or Wiskott-Aldrich syndrome
Genetic diseases such as sickle cell disease, thalassemia, Diamond Blackfan anemia, Hurler syndrome, or adrenoleukodystrophy disorder
A bone marrow transplant has risks, some of which are life-threatening. Your child’s healthcare provider and BMT team will discuss risks and benefits with you before the procedure.
Risks and complications may vary depending on:
The type of BMT
The type of disease the transplant is treating
What medicines are used before the transplant
Your child’s age and overall health
The differences of the tissue match between donor and recipient
Possible complications include:
Infections. Infections are likely with severe bone marrow suppression. This is when not enough blood cells are made in the bone marrow. Medicines are often given to prevent and treat infection.
Low levels of platelets (thrombocytopenia) and red blood cells (anemia). These can be dangerous and even life-threatening. Most children will need multiple blood product transfusions.
Pain. Pain caused by mouth sores and gastrointestinal (GI) irritation is common from chemotherapy and radiation. Pain medicine and good mouth care can help.
Diarrhea, nausea, and vomiting. These may happen with chemotherapy, radiation, and GI irritation. Calories and protein may be given through an IV (intravenous) until your child can eat again and the diarrhea has stopped.
Fluid overload. This most often occurs when the kidneys can’t keep up with the large amount of IV fluids being given. Your child will be watched closely for fluid overload. He or she will be weighed often, will have blood tests, and urine will be measured often. Medicines may be given to help kidney function and get rid of excess fluid.
Breathing problems. Serious lung problems can be caused by infection, airway inflammation, fluid overload, graft-versus-host disease, and bleeding. Your child may need supplemental oxygen to breathe better until problems are treated.
Organ damage. Short-term (temporary) or long-lasting (permanent) liver and heart damage may be caused by infection, graft-versus-host disease, chemotherapy and radiation, or fluid overload. Your child's blood and vital signs will be checked carefully to look for organ damage.
Graft failure. The transplanted cells (graft) may fail to grow in the marrow. This may happen from infection, the disease coming back, or a stem cell count in the donated marrow that was too low. Graft failure may be treated with another bone marrow transplant.
Graft-versus-host disease (GVHD). GVHD can be serious and life-threatening. It happens when the donor’s immune cells attack the recipient's healthy cells. Your child will be watched closely for GVHD. Signs can include diarrhea, fever, rash, skin changes, stomach pain, breathing problems, and decreased liver function. Your child will be given medicines before the transplant to reduce this risk.
Before the transplant:
The bone marrow transplant team gives your child an in-depth evaluation. The team will talk with you about the risks and benefits of transplant and other treatment choices.
Your child will have physical exams and tests. The tests look at your child's blood and organ functions, such as heart, kidney, liver, and lungs.
Your child may need to go to the transplant center up to 10 days before the transplant. A thin, flexible tube (catheter) called a central venous line is surgically placed in a vein in your child’s chest. Blood products and medicines will be given through the catheter.
The days before the transplant are counted as minus days. The day of transplant is considered day 0. Engraftment and recovery following the transplant are counted as plus days. For example, a child may enter the hospital on day -8 to prepare for the BMT. Days +1, +2, and so on, will follow the transplant. There are possible events, complications, and risks linked to each day before, during, and after transplant. The days are numbered to help you and your child know where you are in terms of risks and discharge planning.
Once suitable stem cells are found, your child will get high doses of chemotherapy or radiation (sometimes both) to destroy existing bone marrow. This gives the new bone marrow cells room to grow. This may be called ablative or myeloablative therapy. It stops new blood cells from being made. The bone marrow becomes empty. An empty marrow is needed to make room for the new stem cells to grow and create a new system to make new blood cells.
Next, stem cells are given to your child through an IV in a large vein, often in the chest. This is called a central venous catheter. Getting the stem cells is like having a blood transfusion. The stem cells find their way into the bone marrow. They start growing and making new, healthy blood cells.
During infusion of the bone marrow, your child may have:
After infusion, your child may:
Be at risk for infection
Have some bleeding
Have nausea, vomiting, diarrhea, mouth sores, and extreme weakness
Have some emotional distress
Your child will get supportive care to prevent and treat infections, side effects, and complications.
During this time, your child may:
Spend several weeks in the hospital
Be confined to a very clean environment to reduce the chance of infection
Take multiple antibiotics and other medicines
Need blood transfusions
Be given medicine to prevent graft-versus-host disease
Have daily blood tests
Engraftment of the stem cells happens when the donated cells make their way to the marrow and start making new blood cells. Engraftment usually happens between day +15 and +30. This depends on the type of transplant and the disease being treated. Blood tests will be done often to count blood cells after transplant. Platelets are usually the last type of blood cells to recover.
In some cases, engraftment can be delayed. This can be due to infection, medicines, low donated stem cell count, or graft failure. The new bone marrow may start making cells in the first 30 days after the transplant. But it may take months or years for your child’s immune system to fully recover.
The healthcare team will tell you when your child is ready to go home. This depends on many things, such as:
Extent of engraftment
Your child's overall health
How far you live from the facility
Before you go home, you will be instructed on ways to reduce your child’s risk of infection. These include:
Special air filtered rooms
Frequent bed linen changes
Your child will then need to see the transplant team often to:
See how well the treatment is working
Look for signs of problems such as infection
Treat side effects, infection, and other problems
Long-term success varies from child to child. Your child’s healthcare team will talk with you about your child’s prognosis, follow-up care, and future treatments.
Before you agree to the test or the procedure for your child make sure you know:
The name of the test or procedure
The reason your child is having the test or procedure
What results to expect and what they mean
The risks and benefits of the test or procedure
When and where your child is to have the test or procedure
Who will do the procedure and what that person’s qualifications are
What would happen if your child did not have the test or procedure
Any alternative tests or procedures to think about
When and how you will get the results
Who to call after the test or procedure if you have questions or your child has problems
How much you will have to pay for the test or procedure