Stem cell transplant (bone marrow transplant)

We understand how overwhelming it can be to learn that your child needs a stem cell transplant. Right now, you probably have a lot of questions. What is it? What do we do next?

We’ve tried to provide some answers to those questions in the following pages, and our experts can explain your child’s options fully when you meet with us.

What is bone marrow?

Bone marrow is a soft, spongy tissue found inside the bones. The bone marrow in the hips, breastbone, spine, ribs, and skull contain cells that produce about 95 percent of the body's blood cells.

The three main types of blood cells produced in the bone marrow are:

• red blood cells (erythrocytes), which carry oxygen throughout the body
   
• white blood cells (leukocytes), which help to fight infections
   
• platelets, which help blood to clot

What are stem cells?

Stem cells are immature cells that are able to produce other blood cells that mature and function as needed. Every type of blood cell in the bone marrow begins as a stem cell.

Stem cells are the most important cells in a bone marrow transplant. Once transplanted, they move into your child’s bones and begin to produce the blood cells that are needed by her body.

Hematopoietic stem cells can form any type of blood cell including red blood cells, white blood cells and platelets. They are different from pluripotent stem cells, which can form any type of cell. Stem cell, or bone marrow, transplantation uses hematopoietic stem cells to treat cancers and certain genetic disorders.

For more information on stem cell research, visit our stem cell website.

What is a stem cell transplant?

A stem cell transplant is an infusion of healthy hematopoietic stem cells by IV (through a needle into a vein) in order to treat certain types of cancer, blood disorders and other conditions. Hematopoietic stem cells are a special type of cell found in the bone marrow that can form any type of blood cell: red blood cells, white blood cells and platelets. This is different from pluripotent or embryonic stem cells, which can form any type of cell in the body.

The cells for a stem cell transplant, also called a bone marrow transplant, can come from a related donor—usually a sibling, unrelated donor or the patient himself. The stem cells are infused into your child’s bloodstream and travel to the bone marrow where they begin to make new blood cells.

Why would a stem cell transplant be needed?

The goal of a stem cell transplant is to cure many diseases, including some types of cancer.

A stem cell transplant can be used to:

• replace diseased, non-functional bone marrow with healthy functioning bone marrow (for conditions such aplastic anemia and sickle cell disease)
   
• replace bone marrow and restore its normal function after high doses of chemotherapy or radiation (for diseases such as lymphoma and neuroblastoma)
   
• replace bone marrow with healthy functioning bone marrow to prevent further damage from a genetic disease process (such as Hurler's syndrome and adrenoleukodystrophy)

Stem cell transplantation has risks involved, some of which are life threatening. The risks and benefits must be weighed in a thorough discussion with your child’s stem cell transplant team prior to the procedure.

What diseases can be treated with stem cell transplantation?

Some of the most common conditions that bone marrow transplants are used to treat include:

• leukemia
• lymphomas
• some solid tumors (i.e., neuroblastoma)
• aplastic anemia
• congenital bone marrow failure syndromes
• immune deficiencies (severe combined immunodeficiency disorder, Wiskott-Aldrich Syndrome)
• sickle cell disease
• thalassemia
• metabolic/storage diseases (e.g., Hurler's syndrome, adrenoleukodystrophy disorder)

A stem cell transplant may not be appropriate for your child even if she suffers from one of these diseases. Your child’s physician will determine whether a stem cell transplant is appropriate.

What are the different types of stem cell transplants?

There are three different types of bone marrow transplant:

• autologous stem cell transplant: Your child acts as her own donor. Stem cells are collected by apheresis (a process of collecting stem cells in the blood) and then replaced after intensive treatment. In this situation, the term “stem cell rescue” is often used instead of “transplant.”
   
• allogeneic stem cell transplant: In this type of transplant, stem cells are taken either by bone marrow harvest or apheresis from a genetically-compatible donor, usually a brother or sister. Other donors for allogeneic bone marrow transplants include:
  • A parent — When the donor is a parent and the genetic match is at least half identical to the recipient, the match is called a “haploid-identical match.”
     
  • An identical twin  — Identical twins are considered a complete genetic match for a stem cell transplant. This kind of transplant is called a “syngeneic” transplant. Syngeneic transplants are very rare because the child must have an identical twin.
     
  • An unrelated donor (UBMT or MUD for “matched unrelated donor”) — The genetically matched marrow or stem cells are provided by an unrelated donor. These donors are generally found through national bone marrow registries.
     
• umbilical cord blood transplant: Stem cells are sometimes taken from an umbilical cord immediately after a baby is born. These stem cells can reproduce into mature, functioning blood cells. These cells are tested, typed, counted and frozen until they are ready to be transplanted. The T-lymphocytes, a type of immune cell that can cause transplant complications, are immature, so recipients may have a decreased risk of problems related to transplant. However, because of the limited number of stem cells in the umbilical cord, this type of transplant is generally limited to younger and smaller patients.

How is it decided if my child will have a stem cell transplant?

The decision for your child to undergo a stem cell transplant will be based on many factors including:

• her age, overall health and medical history
• disease status
• availability of a donor
• his tolerance for specific medications, procedures or therapies
• expectations for the course of the disease
• expectations for the course of the transplant

Our stem cell transplant experts will determine whether a stem cell transplant is appropriate for your child and will discuss your child’s treatment options with you and your family

FAQ

Q: What is a stem cell transplant?

A: A stem cell transplant is an infusion of healthy hematopoietic stem cells that’s done to treat certain types of cancer, blood disorders and other conditions. Hematopoietic stem cells are a special type of cell found in the bone marrow that can form any type of blood cell: red blood cells, white blood cells and platelets. This is different from pluripotent or embryonic stem cells, which can form any type of cell in the body.

The cells for a stem cell transplant, also called a bone marrow transplant, can come from a related donor such as a sibling, an unrelated donor or from the patient herself. The stem cells are injected into your child’s bloodstream and travel to the bone marrow where they begin to make new blood cells.

Q: How do I find a matched donor for my child?

A: If your child needs stem cells from someone else, we will determine the best donor possible using HLA-typing, a process that is used to detect your child’s transplant antigens. Antigens are "fingerprints" on the surface of almost all cells of the body.

It’s best to find a donor whose HLA-type is as similar as possible to your child’s. We begin by testing your child and immediate family members.

• Matched or closely matched family donor: About 25 percent of patients have a family member who is a match at the six major sites tested. If a member of your family matches in five or six of the areas, she may be selected as a donor.
   
• Unrelated donor: If no acceptable match is found within your family, the transplant team may conduct a preliminary search for an unrelated donor through the National Marrow Donor Program (NMDP) and more than 46 international and cord bank computerized database registries. The preliminary search of the donor database is free. The transplant team will then ask registries to contact potential matched donors for further testing, which requires insurance coverage or a financial down-payment. The transplant team meets at least weekly to review the status of the donor search, and the Stem Cell Transplant Patient Coordinator will update you and your family on a regular basis.
   
• Mismatched family and haploidentical transplant: Some patients will not have an acceptable donor in the registries. Researchers are currently investigating the possibility of using family members as donors even if they aren’t a close enough match for a traditional transplant. This type of transplant is called a haploidentical transplant. Any family member between the ages of 17 and 60 who has been HLA tested at Dana-Farber Cancer Institute may enroll in the NMDP by contacting the NMDP Donor Center at 617-632-2561.

Q: How does a stem cell transplant work?

A: Stem cells are injected via IV into your child’s blood stream. They make their way into her bone marrow and replace the cells that used to be there. Eventually, these stem cells begin to make new, healthy blood cells. The transplant replaces stem cells that were damaged or defective and, as a result, it can cure certain cancers, blood disorders and genetic defects.

Q: How long does it take to find an unrelated donor? 

A: Identifying a donor involves many factors, so the length of a donor search varies. How many possible matches exist, how long it takes to receive samples to confirm typing, and donor availability can all affect the length of a donor search. Our Stem Cell Transplant Patient Coordinator will keep you and your family updated on the status of the search.

Q: What is the cost of typing for donors? 

A: Through Dana-Farber/Children's Hospital Cancer Center, donor typing is free for immediate family members at Dana-Farber Cancer Institute's blood center. Extended family members and friends interested in becoming a marrow donor should contact the National Marrow Donor Program (NMDP), which will provide typing services for a cost of $60. This fee may be covered by the donor's health care insurance plan.

Q: What is the donor process?

A: A bone marrow donor process begins with a physical evaluation, which includes basic blood tests and screening for infectious disease. If the donor is approved, she will have to attend a pre-operative appointment before the bone marrow harvest, a surgical operation to collect the bone marrow.

Q: How long do donors have to stay in the hospital after the bone marrow harvest? 

A: Bone marrow donors stay one night for observation after the bone marrow harvest. If the donor is a child, she will be admitted to the transplantation unit if a bed is available. If the donor is an adult, the harvest and overnight stay occur at Brigham and Women's Hospital.

Q: Can I contact my child's unrelated bone marrow donor? 

A: For the first year after your child's transplant you can have anonymous contact with the donor. Communication is usually facilitated through the National Marrow Donor Program. You may send written correspondence, but no personal information, names or geographical references are allowed. After one year, if both parties agree, you may directly contact the donor. In some cases, this waiting period may be longer due to international regulations.

For more information on stem cell transplantation, visit our research site.

Q: How long will my child have to stay in the hospital?

A: Your child’s length of stay will depend on many factors, including:

• the success of engraftment
• the presence of complications
• your child’s overall health
• your distance from Children’s

Your child’s length of stay can vary significantly depending on these factors. On average, however, children stay in the hospital for about 30 to 40 days.

Useful terms

Here are some important terms to know:

Allogeneic stem cell transplant (Allo): This is the infusion of another person’s bone marrow or stem cells after high dose chemotherapy and/or radiation.

Autologous stem cell transplant (Auto): This is the infusion of a patient’s own bone marrow or stem cells after receiving high dose chemotherapy and/or radiation.

Graft-versus-host disease (GVHD): This is a rejection process, in which the transplanted bone marrow (the graft) attacks tissues in the recipient (the host). The organs usually affected are the skin, gastrointestinal tract and liver.

HLA typing: This is the process of identifying the genetic structure of circulating white blood cells. HLA typing, also known as tissue-typing, is performed to determine whether a donor can be found for a bone marrow transplant. Blood is removed from a vein for this test.

Peripheral-blood stem cell transplant (PBSCT): This is a type of transplant in which circulating stem cells are collected and later infused back into a given patient after very high doses of chemotherapy or radiation therapy have been given.

Stem cell: This is the building block of bone marrow and blood formation. Stem cells form white blood cells, red blood cells and platelets. Hematopoietic stem cells are used in stem cell transplants.

Questions to ask your child’s doctor

After you learn that your child may need a stem cell transplant, you may feel overwhelmed with information. It can be easy to lose track of the questions that occur to you.

Lots of parents find it helpful to jot down questions as they arise – that way, when you talk to your child’s doctors, you can be sure that all of your concerns are addressed.

If your child is old enough, you may want to suggest that she write down what she wants to ask her health care provider, too.

Some of the questions you may want to ask include:

• How much experience has this hospital/my child’s doctor had with stem cell transplants?
   
• What are the possible short and long-term complications?
   
• How will they be addressed?
   
• What is the likelihood of cure?
   
• Is it possible that my child could need another transplant?
   
• What services are available to help my child and my family cope?