What Is a Blood and Marrow Stem Cell
Transplant?
A blood and marrow stem cell transplant replaces a
person's abnormal stem cells with healthy ones from another person (a donor).
This procedure allows the recipient to get new stem cells that work properly.
Stem cells are found in bone marrow, a sponge-like
tissue inside the bones. Stem cells develop into the three types of blood cells
that the body needs:
- Red blood cells, which carry oxygen through the
body
- White blood cells, which fight infection
- Platelets (PLATE-lets), which help the blood
clot
Small numbers of stem cells also are found in the
blood and in the umbilical cord (the cord that connects a fetus to its mother's
placenta).
Another type of stem cell, called an embryonic
(em-bre-ON-ik) stem cell, can develop into any type of cell in the body. These
cells aren't found in bone marrow.
Overview
Doctors use stem cell transplants to treat people
who have:
- Certain cancers, such as leukemia (lu-KE-me-ah).
The high doses of chemotherapy and radiation used to treat some cancers can
severely damage or destroy bone marrow. A transplant replaces the stem cells
that the treatment destroyed.
- Severe blood diseases, such as
thalassemias
(thal-a-SE-me-ahs),
aplastic
anemia (uh-NEE-me-uh), and
sickle
cell anemia. In these diseases, the body doesn't make enough red blood
cells or they don't work properly.
- Certain immune-deficiency diseases that prevent
the body from making some kinds of white blood cells. Without these cells, a
person can develop life-threatening infections. A transplant provides stem
cells to replace the missing white blood cells.
Types of Transplants
The two main types of stem cell transplants are
autologous (aw-TOL-o-gus) and allogenic (a-LO-jen-ik).
For an autologous transplant, your own stem cells
are collected and stored for use later on. This works best when you still have
enough healthy stem cells, even though you’re sick. If you have cancer,
the cancer cells are removed or destroyed from the collected cells.
For an allogenic transplant, you get stem cells from
a donor. The donor can be a relative (like a brother or sister) or an unrelated
person. You also may get stem cells from umbilical cord blood donated by an
unrelated person.
To prevent problems, the donor's stem cells should
match yours as closely as possible. Donors and recipients are matched through a
blood test called HLA tissue typing.
Collection Process
Stem cells used in transplants are collected from
donors in several ways.
A procedure called apheresis (a-fer-E-sis) may be
used. For this procedure, a needle is placed in the donor's arm to draw blood.
Then, his or her blood is passed through a machine that removes the stem cells
from the blood. The rest of the blood is returned to the donor.
Stem cells may be collected directly from a donor's
pelvis. This procedure isn't used very much anymore because it must be done in
a hospital using local or general anesthesia (AN-es-THE-ze-a). For this
procedure, a hollow needle is inserted repeatedly into the pelvis, and marrow
is sucked out of the bone.
Blood containing stem cells may be collected from an
umbilical cord and placenta after a baby is born. The blood is frozen and
stored at a cord blood bank for future use.
Outlook
Stem cell transplants have serious risks. Some
complications are life threatening. For some people, however, stem cell
transplants are the best hope for a cure or a longer life.
Who Needs a Blood and Marrow Stem Cell Transplant?
Your doctor may recommend a blood and marrow stem
cell transplant if you have a disease or condition that prevents your body from
making enough healthy blood cells. Examples of such diseases and conditions
include:
- Some cancers, such as leukemia, lymphoma,
myeloma, and breast cancer
- Severe blood diseases, such as
thalassemias,
aplastic
anemia, and
sickle
cell anemia
- Certain immune-deficiency diseases, such as
severe combined immunodeficiency syndrome, congenital neutropenia
(kon-JEN-i-tal NU-tro-PE-ne-ah), and chronic granulomatous (gran-yu-LOM-a-tus)
disease
Your primary care doctor and an oncologist or
hematologist will determine whether you need a stem cell transplant. An
oncologist specializes in diagnosing and treating cancer. A hematologist
specializes in diagnosing and treating blood diseases and conditions.
When deciding whether you need a stem cell
transplant, your doctors will consider:
- The type of disease you have and how severe it
is
- Your age and overall health
- Other possible treatment options
You also will have tests to make sure you're healthy
enough to have the procedure. Your doctors will want to find out whether you
have any medical problems that could cause complications after the transplant.
(See
"What
To Expect Before a Blood and Marrow Stem Cell Transplant" for more
information.)
What To Expect Before a Blood and Marrow Stem Cell
Transplant
Finding a Donor
If you're going to get stem cells from another
person, your doctors will want to find a donor whose stem cells match yours as
closely as possible.
A close match can reduce the risk that your immune
system will attack the donor cells. It also reduces the risk that cells from
the donor's marrow or blood will attack your body.
HLA Tissue Typing
People having transplants are matched with donors
through a test called HLA tissue typing. HLAs are proteins found on the surface
of white blood cells. Your immune system uses HLAs to tell which cells belong
to you and which don't.
Because HLA markers are inherited, an identical twin
is the best donor match. Brothers or sisters also can be good matches. However,
many people don't have a good match in their families.
If no matching donor is found in your family, the
search widens to include people outside the family. Millions of volunteer
donors are registered with the
National Marrow Donor Program. Your doctors will look for:
- Donors who are an HLA match but not a family
member
- Family members who aren't exact HLA matches
- Unrelated donors who aren't exact HLA matches
- Umbilical cord blood that's an HLA match
People who provide their own stem cells for later
use don't need to go through HLA matching.
Medical Tests and Exams
You also will need other medical tests and exams
before a stem cell transplant. Your doctors will want to make sure you're
healthy enough to have a transplant. They also will want to find out whether
you have any medical problems that could cause complications after the
transplant.
Blood Tests
Blood tests are used to check for HIV, herpes,
pregnancy, and other conditions. These tests help doctors learn about your
overall health.
Chest X Ray and Lung Function Tests
A
chest
x ray creates a picture of the structures in your chest, such as your heart
and lungs. It can show whether your heart is enlarged or whether your lungs
have extra blood flow or extra fluid.
Lung
function tests tell doctors whether you have a lung infection or disease.
They also show how well your blood is able to carry oxygen through your
body.
Computed Tomography Scan, Skeletal X Ray, or Bone
Scan
These tests provide detailed images of your body.
They're used to see whether you have any tumors in your bones that might
complicate a transplant.
Dental Exam
A complete dental exam is used to check for problems
that might cause an infection after your transplant.
Heart Tests
Heart tests, including
EKG
(electrocardiogram) and
echocardiography,
are used to find any conditions that might get worse after the transplant.
An EKG detects and records your heart’s
electrical activity. Echocardiography uses sound waves to create a moving
picture of your heart. The picture shows how well your heart is working and its
size and shape.
Bone Marrow Biopsy
A
bone
marrow biopsy helps show whether your bone marrow is making enough healthy
blood cells. If you're being treated for a blood cancer, this test shows
whether your cancer is inactive.
What To Expect During a Blood and Marrow Stem Cell
Transplant
A blood and marrow stem cell transplant has three
parts: preparation, transplant, and recovery in the hospital.
Preparation
You’ll check in to the hospital a few days
before the transplant. Using a simple surgical procedure, doctors will place a
tube in a large vein in your chest. This tube is called a central venous
catheter or a central line. It allows easy access to your bloodstream.
Doctors will use the central line to give you
fluids, medicines, and blood products and to collect blood samples. The tube
will stay in place for at least 6 months after your transplant.
To prepare your body for the transplant, your
doctors will give you high doses of chemotherapy and possibly radiation.
This treatment destroys the stem cells in your bone
marrow that aren't working right. It also suppresses your body's immune system
so that it won't attack the new stem cells after the transplant. Some people
may get more than one cycle of chemotherapy before their transplants.
The high doses of chemotherapy and radiation can
cause side effects, including nausea (feeling sick to your stomach), vomiting,
diarrhea, and tiredness. Medicines can help with these symptoms.
In older patients or those who aren't very strong,
doctors may choose "reduced-intensity" treatment. This involves lower doses of
chemotherapy or radiation.
Because your immune system is very weak after this
treatment, you can easily get an infection. As a result, you’ll stay in a
hospital room that has special features that keep the room as clean as
possible.
Doctors, nurses, and visitors will have to wash
their hands carefully and follow other procedures to make sure you don't get an
infection. For example, they may wear face masks while in contact with you.
Preparation before a stem cell transplant may take
up to 10 days. The time depends on your medical situation, general health, and
whether you need chemotherapy or chemotherapy and radiation.
Transplant
A stem cell transplant is like a
blood
transfusion. During the procedure, you get donated stem cells through your
central line. Once the stem cells are in your body, they travel to your bone
marrow and begin making new red blood cells, white blood cells, and platelets.
You're awake during the transplant. You may get
medicine to help you stay calm and relaxed. Doctors and nurses will check your
blood pressure, breathing, and pulse, and they’ll watch for signs of fever
or chills. Side effects of the transplant can include headache or nausea, but
you may not have side effects.
The transplant takes an hour or more. This includes
the time to set up the procedure, the transplant itself, and time to check you
afterward.
Recovery in the Hospital
You’ll stay in the hospital for weeks or even
months after your stem cell transplant. In the first few days after the
procedure, your blood cell levels will continue to go down. This is because of
the chemotherapy and/or radiation you got before the transplant.
Your doctors will test your blood 7 to 10 days after
the transplant to see whether new blood cells have begun to grow. They’ll
check your blood counts every day to track your progress.
You’ll stay in the hospital until your immune
system recovers and your doctors are sure that your transplant was successful.
During your time in the hospital, your doctors and nurses will carefully watch
you for side effects from chemotherapy and radiation, infection, and
graft-versus-host disease (GVHD) and graft failure.
Having support from family and friends, especially
having someone who can be with you most days in the hospital, can help you
recover.
Side Effects From Chemotherapy or Radiation
The chemotherapy and possible radiation you get
before the stem cell transplant have side effects. These side effects begin to
occur a few days after the transplant. Some of these side effects are painful
or uncomfortable; others are very serious.
Side effects include:
- Painful sores in the mouth.
- Nausea, diarrhea, and intestinal cramps.
- Skin rashes.
- Hair loss.
- Liver damage. This occurs in about 10 percent of
people who go through the transplant preparation.
- Interstitial pneumonia. This is a type of
pneumonia that affects certain tissues in the lungs. It affects about 5 percent
of people who go through the transplant preparation.
Doctors use mouth rinses, medicines, and other
methods to treat these side effects. Some go away on their own once your blood
cells begin to grow and your immune system recovers.
Infection
You can easily get an infection after the transplant
because your immune system is weak. Some infections are serious. Infections can
be caused by:
- Bacteria, such as those in your mouth or around
your central line
- Viruses, such as herpes or cytomegalovirus
- Fungus or yeast, such as candida
To prevent infections, you’ll stay in a private
room. The air will be filtered to keep germs out. Doctors, nurses, and others
who visit you will wear face masks and wash their hands very carefully. Your
doctor may have you take medicine to fight infections even if you don't already
have an infection.
You also can take other steps to prevent
infections:
- Bathe or shower daily.
- Carefully clean your teeth and gums.
- Keep the area clean where your central line
enters your body.
- Avoid foods, such as raw fruits and vegetables,
that may have harmful bacteria.
Graft-Versus-Host Disease and Graft Failure
Donated stem cells can attack your body. This is
called graft-versus-host disease. Your immune system also can attack the
donated stem cells. This is called graft failure. These events can be minor or
life threatening. They can happen soon after transplant or can develop slowly
over months.
GVHD and graft failure are described more fully in
"What
Are the Risks of a Blood and Marrow Stem Cell Transplant?"
What To Expect After a Blood and Marrow Stem Cell
Transplant
You’ll stay in the hospital for weeks or even
months after your blood and marrow stem cell transplant. Your doctors will want
to be sure that you're healthy and strong enough to go home.
They’ll want to make sure:
- Your bone marrow is making enough healthy blood
cells
- You have no severe complications
- You feel well and any mouth sores and/or
diarrhea have improved or gone away
- Your appetite has improved
- You have no fever or vomiting
During the first weeks and months after you leave
the hospital, you’ll make frequent trips to an outpatient clinic. This
allows your doctors to track your progress. These visits will happen less often
over time.
Staff at the clinic will teach you and your
caregiver how to care for your central line (which will stay in place for at
least 6 months after your transplant), how to watch for and prevent infections,
and other ways to care for you. They also will tell you who to call and what to
do in case of an emergency.
Recovery from a stem cell transplant can be slow. It
takes 6 to 12 months to recover normal blood cell levels and immune function.
During this time, it's important for you to take steps to reduce the risk of
infection, get plenty of rest, and follow your doctors' instructions about
medicines and checkups.
What Are the Risks of a Blood and Marrow Stem Cell
Transplant?
The main risks of a blood and marrow stem cell
transplant are infection, graft-versus-host disease (GVHD), and graft
failure.
Infection
You can easily get an infection after the transplant
because your immune system is weak. The risk of infection decreases as your
immune system recovers.
You can take steps to prevent infections, such as
washing your hands and staying away from crowds. Doctors use medicines to
prevent and treat infections.
Transplant recipients are sometimes given vaccines
to prevent viruses and infections, such as the flu and
pneumonia.
Graft-Versus-Host Disease
GVHD is a common complication for people who get
stem cells from a donor. In GVHD, the new stem cells attack your body.
Acute GVHD occurs within 90 to 100 days after the
transplant. Chronic GVHD begins more than 90 to 100 days after the transplant
or goes beyond 90 days after the transplant.
GVHD can be minor or life threatening. Signs and
symptoms include:
- A rash that starts on the palms of your hands
and soles of your feet and spreads to your mid-section. Over time, the rash may
cover your entire body. Skin can blister or peel if the rash is very bad.
- Nausea (feeling sick to your stomach), vomiting,
loss of appetite, abdominal cramps, and diarrhea. Doctors determine how bad
GVHD is based on the severity of diarrhea.
- Jaundice (yellowing of the skin and whites of
the eyes) and abdominal pain. These symptoms indicate liver damage.
Medicines are used to treat GVHD. Acute GVHD is
treated with glucocorticoids, such as methyl prednisone, prednisone in
combination with cyclosporine, antithymocyte globulin, or monoclonal
antibodies.
Chronic GVHD is treated with steroids—usually
cyclosporine and prednisone on alternating days.
Older people, people who have had acute GVHD before,
and people who received stem cells from mismatched or unrelated donors are more
likely to develop GVHD.
Doctors can reduce your chances of getting GVHD
by:
- Closely matching your stem cells to your donor's
through HLA tissue typing.
- Using medicines to suppress your immune system.
- Removing some types of T cells from donor cells.
T cells attack your body in GVHD.
- Using umbilical cord blood as the source of
donor cells.
Graft Failure
Graft failure occurs if your immune system rejects
the new stem cells. It also can occur if not enough stem cells are used, the
new stem cells are damaged during storage, or your bone marrow is damaged after
the transplant.
Graft failure is more likely in people who receive
less preparation for their transplants. People who get stem cells from poorly
matched donors also are more likely to have graft failure.
Other Risks
Complications from chemotherapy and radiation
treatment (used to prepare for a transplant) can occur long after a transplant.
These complications may include infertility, cataracts, new cancers, and damage
to the liver, kidneys, lungs, or heart.
Cancer Relapse
In some people who get stem cell transplants to
treat cancer (such as leukemia), the cancer eventually comes back. This happens
more often in people who use their own stem cells for the transplant (an
autologous transplant) than in people who get stem cells from a donor (an
allogenic transplant).
This difference occurs because stem cells received
from another person recognize new cancer cells as foreign and destroy them.
This is called the graft-versus-tumor effect. A person’s own stem cells
don’t recognize the new cancer cells as foreign. This allows the cancer
cells to grow and multiply.
Doctors use immunotherapy to help prevent and treat
the recurrence of cancer in people who’ve received a stem cell transplant.
Immunotherapy is treatment that stimulates the immune system to attack cancer
cells.
Key Points
- A blood and marrow stem cell transplant replaces
a person's abnormal stem cells with healthy stem cells from another person (a
donor).
- Stem cells are found in bone marrow, a
sponge-like tissue inside the bones. Stem cells develop into red blood cells,
white blood cells, and platelets.
- Doctors use stem cell transplants to treat
people whose bone marrow can't make enough healthy blood cells. These people
may have some types of cancer, severe blood diseases, or certain
immune-deficiency diseases.
- In an autologous stem cell transplant, your own
stem cells are collected and stored for later use. In an allogenic stem cell
transplant, you get stem cells from another person.
- To determine whether you need a stem cell
transplant, your doctors will consider the type of disease you have and how
serious it is, your age and overall health, and other treatment options.
- People having transplants are matched with
donors through HLA tissue typing. A close match can improve the chances of a
successful transplant. People who provide their own stem cells for later use
don't need HLA tissue typing.
- You also will need other types of tests before
the stem cell transplant to make sure you're healthy enough to have the
procedure.
- To prepare your body for the transplant, doctors
give high doses of chemotherapy and possibly radiation. This is done to destroy
the stem cells in your bone marrow that aren't working properly and to suppress
your body's immune system.
- During the transplant, you’ll get donated
stem cells in a procedure that's like a
blood
transfusion. Once the new stem cells are in your body, they travel to your
bone marrow and begin making new blood cells.
- You’ll need to stay in the hospital until
your immune system recovers and doctors can be sure that the transplant was
successful. This can take weeks or months.
- During your time in the hospital, your doctors
and nurses will pay special attention to side effects of the pretransplant
chemotherapy and radiation. They also will watch for infection,
graft-versus-host disease (GVHD), and graft failure.
- It takes 6 to 12 months to recover normal blood
cell levels and immune function after a stem cell transplant. During this time,
it's important to reduce your risk of infection, get plenty of rest, and follow
your doctors' instructions about medicines, checkups, and vaccines.
- Stem cell transplants have serious risks and can
have life-threatening complications. For some people, however, stem cell
transplants are the best hope for a cure or a longer life.
Links to Other Information About Blood and Marrow
Stem Cell Transplants
NHLBI Resources
Non-NHLBI Resources
Clinical Trials
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