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Thalassemia
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Treatment
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Bone Marrow Transplant
A blood and marrow stem cell transplant replaces
your abnormal or faulty stem cells with healthy
ones from another person (a donor). Stem cells
are the cells inside bone marrow that make red
blood cells and other types of blood cells.
A stem cell transplant is the only treatment
that can cure thalassemia. But only a small
number of people who have the severe form of the
disorder are able to find a good match among
donors and have the risky procedure.
Bone marrow is a spongy
tissue found inside bones. The bone marrow in
the breast bone, skull, hips, ribs and spine
contains stem cells that produce the body's
blood cells. These blood cells include white
blood cells (leukocytes), which fight infection;
red blood cells (erythrocytes), which carry
oxygen to and remove waste products from organs
and tissues; and platelets, which enable the
blood to dot
In patients with leukemia, aplastic anemia, and
some immune deficiency diseases, the stem cells
in the bone marrow malfunction, producing an
excessive number of defective or immature blood
cells (in the case of leukemia) or low blood
cell counts (in the case of aplastic anemia).
The immature or defective blood cells interfere
with the production of normal blood cells,
accumulate in the bloodstream and may invade
other tissues.
Large doses of chemotherapy and/or radiation are
required to destroy the abnormal stem cells and
abnormal blood cells. These therapies, however,
not only kill the abnormal cells but can destroy
normal cells found in the bone marrow as well.
Similarly, aggressive chemotherapy used to treat
some lymphomas and other cancers can destroy
healthy bone marrow. A bone marrow transplant
enables physicians to treat these diseases with
aggressive chemotherapy and/or radiation by
allowing replacement of the diseased or damaged
bone marrow after the chemotherapy/radiation
treatment.
While bone marrow transplants do not provide 100
percent assurance that the disease will not
recur, a transplant can increase the likelihood
of a cure or at least prolong the period of
disease-free survival for many patients.
Types of Bone Marrow Transplants
In a bone marrow transplant, the patient's
diseased bone marrow is destroyed and healthy
marrow is infused into the patient's
blood-stream. In a successful transplant, the
new bone marrow migrates to the cavities of the
large bones, engrafts and begins producing
normal blood cells.
If bone marrow from a donor is used, the
transplant is called an "allogeneic" BMT, or "syngeneic"
BMT if the donor is an identical twin. In an
allogeneic BMT, the new bone marrow infused into
the patient must match the genetic makeup of the
patient's own marrow as perfectly as possible.
Special blood tests are conducted to determine
whether or not the donor's bone marrow matches
the patient's. If the donor's bone marrow is not
a good genetic match, it will perceive the
patient's body as foreign material to be
attacked and destroyed. This condition is known
as graft-versus-host disease (GVHD) and can be
life-threatening. Alternatively, the patient's
immune system may destroy the new bone marrow.
This is called graft rejection.
There is a 35 percent chance that a patient will
have a sibling whose bone marrow is a perfect
match. If the patient has no matched sibling, a
donor may be located in one of the international
bone marrow donor registries, or a mis-matched
or autologous transplant may be considered.
In some cases, patients may be their own bone
marrow donors. This is called an autologous BMT
and is possible if the disease afflicting the
bone marrow is in remission or if the condition
being treated does not involve the bone marrow
(e.g. breast cancer, ovarian cancer, Hodgkin's
disease, non-Hodgkin's lymphoma, and brain
tumors). The bone marrow is extracted from the
patient prior to transplant and may be "purged"
to remove lingering malignant cells (if the
disease has afflicted the bone marrow).
Preparation for Bone Marrow Transplant
A successful transplant requires the patient be
healthy enough to undergo the rigors of the
transplant procedure. Age, general physical
condition, the patient's diagnosis and the stage
of the disease are all considered by the
physician when determining whether a person
should undergo a transplant.
Prior to a bone marrow transplant, a battery of
tests is carried out to ensure the patient is
physically capable of undergoing a transplant.
Tests of the patient's heart, lung, kidney and
other vital organ functions are also used to
develop a patient "baseline" against which
post-transplant tests can be compared to
determine if any body functions have been
impaired. The pre-transplant tests are usually
done on an outpatient basis.
A successful bone marrow transplant requires an
expert medical team - doctors, nurses, and other
support staff - who are experienced in bone
marrow transplants, can promptly recognize
problems and emerging side effects, and know how
to react swiftly and properly if problems do
arise. A good bone marrow transplant program
will also recognize the importance of providing
patients and their families with emotional and
psychological support before, during and after
the transplant, and will make personal and other
support systems readily available to families
for this purpose.
Bone marrow Harvest
Regardless of whether the patient or a donor
provides the bone marrow used in the transplant,
the procedure used to collect the marrow - the
bone marrow harvest - is the same. The bone
marrow harvest takes place in a hospital
operating room, usually under general
anesthesia. It involves little risk and minimal
discomfort.
While the patient is under anesthesia, a needle
is inserted into the cavity of the rear hip bone
or "iliac crest" where a large quantity of bone
marrow is located. The bone marrow a thick, red
liquid - is extracted with a needle and syringe.
Several skin punctures on each hip and multiple
bone punctures are usually required to extract
the requisite amount of bone marrow. There are
no surgical incisions or stitches involved -
only skin punctures where the needle was
inserted.
The amount of bone marrow harvested depends on
the size of the patient and the concentration of
bone marrow cells in the donor's blood. Usually
one to two quarts of marrow and blood are
harvested. While this may sound like a lot, it
really only represents about 2% of a person's
bone marrow, which the body replaces in four
weeks.
When the anesthesia wears off, the donor may
feel some discomfort at the harvest site. The
pain will be similar to that associated with a
hard fall on the ice and can usually be
controlled with Tylenol. Donors who are not also
the BMT patient are usually discharged after an
overnight stay and can fully resume normal
activities in a few days.
For autologous transplants, the harvested bone
marrow will be frozen (cryopreserved) and stored
at a temperature between -80 and -196 degrees
centigrade until the day of transplant. It may
first be "purged" to remove residual cancerous
cells that can't be easily identified under the
microscope
In allogeneic BMTs, the bone marrow may be
treated to remove "T-cells" (T cell depletion)
to reduce the risk of graft-versus-host disease
(see page 94). It will then be transferred
directly to the patient's room for infusion.
Preparative Regimen
A patient admitted to the bone marrow transplant
unit will first undergo several days of
chemotherapy and/or radiation which destroys
bone marrow and cancerous cells and makes room
for the new bone marrow. This is called the
conditioning or preparative regimen. The exact
regimen of chemotherapy and/or radiation varies
according to the disease being treated and the
"protocol" or preferred treatment plan of the
facility where the BMT is being performed.
Prior to conditioning, a small flexible tube
called a catheter (sometimes called a "Hickman®"
or central venous line) will be inserted into a
large vein in the patient's chest just above the
heart. This tube enables the medical staff to
administer drugs and blood products to the
patient painlessly, and to withdraw the hundreds
of blood samples required during the course of
treatment without inserting needles into the
patient's arms or hands.
The dosage of chemotherapy and/or radiation
given to patients during conditioning is much
stronger than dosages administered to patients
with the same disease who are not undergoing a
BMT. Patients may become weak, irritable and
nauseous. Most BMT centers administer
anti-nausea medications to minimize discomfort.
Transplant
A day or two following the chemotherapy
and/or radiation treatment, the transplant will
occur. The bone marrow is infused into the
patient intravenously in much the same way that
any blood product is given. The transplant is
not a surgical procedure. It takes place in the
patient's room, not an operating room.
Patients are checked frequently for signs of
fever, chills, hives and chest pains while the
bone marrow is being infused. When the
transplant is completed, the days and weeks of
waiting begin.
Engraftment
The two to four weeks immediately following
transplant are the most critical. The high-dose
chemotherapy and/or radiation given to the
patient during conditioning will have destroyed
the patient's bone marrow, crippling the body's
"immune" or defense system. As the patient waits
for the transplanted bone marrow to migrate to
the cavities of the large bones, set up
housekeeping or "engraft," and begin producing
normal blood cells, he or she will be very
susceptible to infection and excessive bleeding.
Multiple antibiotics and blood transfusions will
be administered to the patient to help prevent
and fight infection. Transfusions of platelets
will be given to prevent bleeding. Allogeneic
patients will receive additional medications to
prevent and control graft-versus-host disease.
Extraordinary precautions will be taken to
minimize the patient's exposure to viruses and
bacteria. Visitors and hospital personnel will
wash their hands with antiseptic soap and, in
some cases, wear protective gowns, gloves and/or
masks while in the patient's room. Fresh fruits,
vegetables, plants and cut flowers will be
prohibited in the patient's room since they
often carry fungi and bacteria that pose a risk
of infection. When leaving the room, the patient
may wear a mask, gown and gloves as a barrier
against bacteria and virus, and as a reminder to
others that he or she is susceptible to
infection. Blood samples will be taken daily to
determine whether or not engraftment has
occurred and to monitor organ function. When the
transplanted bone marrow finally engrafts and
begins producing normal blood cells, the patient
will gradually be taken off the antibiotics, and
blood and platelet transfusions will generally
no longer be required. once the bone marrow is
producing a sufficient number of healthy red
blood cells, white blood cells and platelets,
the patient will be discharged from the
hospital, provided no other complications have
developed. BMT patients typically spend four to
eight weeks in the hospital.
A bone marrow transplant is a physically,
emotionally, and psychologically taxing
procedure for both the patient and family. A
patient needs and should seek as much help as
possible to cope with the experience. "Toughing
it out" on your own is not the smartest way to
cope with the transplant experience.
The bone marrow transplant is a debilitating
experience. Imagine the symptoms of a severe
case of the flu - nausea, vomiting, fever,
diarrhea, extreme weakness. Now imagine what
it's like to cope with the symptoms not just for
several days, but for several weeks. That
approximates what a BMT patient experiences
during hospitalization.
During this period the patient will feel very
sick and weak. Walking, sitting up in bed for
long periods of time, reading books, talking on
the phone, visiting with friends or even
watching TV may require more energy than the
patient has to spare.
Complications can develop after a bone marrow
transplant such as infection, bleeding,
graft-versus-host disease, or liver disease,
which can create additional discomfort. The
pain, however, is usually controllable by
medication. In addition, mouth sores can develop
that make eating and swallowing uncomfortable.
Temporary mental confusion sometimes occurs and
can be quite frightening for the patient who may
not realize it's only temporary. The medical
staff will help the patient deal with these
problems.
Handling the emotional stress
In addition to the physical discomfort
associated with the transplant experiance there
is emotional and psychological discomfort as
well. Some patients find the emotional and
psychological stress more problematic than the
physical discomfort.
The psychological and emotional stress stems
from several factors. First, patients undergoing
transplants are already traumatized by the news
that they have a life-threatening disease. While
the transplant offers hope for their recovery,
the prospect of undergoing a long, arduous
medical procedure is still not pleasant and
there's no guarantee of success.
Second, patients undergoing a transplant can
feel quite isolated. The special precautions
taken to guard against infection while the
immune system is impaired can leave a patient
feeling detached from the rest of the world and
cut off from normal human contact. The patient
is housed in a private room, sometimes with
special air-filtering equipment to purify the
air. The number of visitors is restricted and
visitors are asked to wear gloves, masks and/or
other protective clothing to inhibit the spread
of bacteria and virus while visiting the
patient. When the patient leaves the room, he or
she may be required to wear a protective mask,
gown and/or gloves as a barrier against
infection. This feeling of isolation comes at
the very time in a patient's life when familiar
surroundings and close physical contact with
family and friends are most needed.
'Helplessness" is also a common feeling among
bone marrow transplant patients, which can breed
further feelings of anger or resentment. For
many, it's unnerveing to be totally dependent on
strangers for survival, no matter how competent
they may be. The fact that most patients are
unfamiliar with the medical jargon used to
describe the transplant procedure compounds the
feeling of helplessness. Some also find it
embarrassing to be dependent on strangers for
help with basic daily functions such as using
the washroom.
The long weeks of waiting for the transplanted
marrow to engraft, for blood counts to return to
safe levels, and for side effects to disappear
increase the emotional trauma. Recovery can be
like a roller coaster ride: one day a patient
may feel much better, only to awake the next day
feeling as sick as ever.
After being discharged from the hospital, a
patient continues recovery at home (or at
lodging near the transplant center if the
patient is from out of town) for two to four
months. Patients usually cannot return to
full-time work for up to six months after the
transplant.
Though patients will be well enough to leave the
hospital, their recovery will be far from over.
For the first several weeks the patient may be
too weak to do much more than sleep, sit up, and
walk a bit around the house. Frequent visits to
the hospital or associated clinic will be
required to monitor the patient's progress, and
to administer any medications and/or blood
products needed. It can take six months or more
from the day of transplant before a patient is
ready to fully resume normal activities.
During this period, the patient's white blood
cell counts are often too low to provide normal
protection against the viruses and bacteria
encountered in everyday life. Contact with the
general public is therefore restricted. Crowded
movie theaters, grocery stores, department
stores, etc. are places recovering BMT patients
avoid during their recuperation. Often patients
will wear protective masks when venturing
outside the home.
A patient will return to the hospital or clinic
as an outpatient several times a week for
monitoring, blood transfusions, and
administration of other drugs as needed.
Eventually, the patient becomes strong enough to
resume a normal routine and to look forward to a
productive, healthy life.
Life after the Transplant
It can take as long as a year for the new bone
marrow to function normally. Patients are
closely monitored during this time to identify
any infections or complications that may
develop.
Life after transplant can be both exhilarating
and worrisome. On the one hand, it's exciting to
be alive after being so close to death. Most
patients find their quality of life improved
after transplant.
Nonetheless, there is always the worry that
relapse will occur. Furthermore, innocent
statements or events can sometimes conjure up
unpleasant memories of the transplant experience
long after the patient has recovered. It can
take a long time for the patient to come to
grips with these difficulties.
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