Definitions of
Bone Marrow Transplantation Terms
A
| B | C | D
| F | G | H
| L | M | N
| O | P | R
| S | T | W
ALL
Acute
Lymphoblastic Leukemia is a usually rapidly progressive
malignant disorder involving the production of immature white blood
cells (BLASTS) which results in the replacement of normal bone marrow
with blast cells. Also called Acute Lymphocytic Leukemia. Appears
most commonly in children, but can occur in adults.
AML
Acute
Myelogenous Leukemia is a malignant disorder involving the white
cells which results in the excessive accumulation of myeloid blast
cells in both the bone marrow and the bloodstream. AML occurs in
all ages and is the more common acute leukemia in adults. AML affects
a different type of white cells than those affected by ALL.
ANLL
Acute
Non-Lymphocytic Leukemia. See AML. Terminology for acute
leukemia's which are not lymphocytic.
Allogeneic
bone marrow transplant
Any
bone marrow transplant between two individuals, whether they are
related or unrelated.
Anemia
Decreased
red cell production resulting in a deficiency in the oxygen-carrying
capacity of the blood. Measured in unit volume concentrations
of hemoglobin, red blood cell volume and red blood cell number.
Antigen
A
substance that induces the production of antibodies.
Aplastic
Anemia
Bone
marrow failure with markedly decreased production of white blood
cells, red blood cells and platelets leading to increased risk of
infection and bleeding.
Autologous
bone marrow transplant
A
portion of the patient's own marrow is removed, stored and then
returned to the body after the patient receives high doses of chemotherapy
and/or radiation therapy. Sometimes the portion of marrow
is purged of cancer cells before being returned to the patient.
Blank
Individuals
have the ability to express two HLA antigens within each category
of antigens (one set being inherited from each biological parent).
When an individual has apparently inherited the same antigen type
from both parents, the HLA typing of that individual is designated
by the shared HLA antigen followed by a "blank" (-).
For example, if one parent contributes an HLA-A2, B7m, DR4 set of
antigens and the second parent contributes an HLA-A2, B8, DR4 set,
the child's HLA typing will be denoted as HLA-A2,-:B7,8;DR4-.
Blast Cells
Blood
cells still in an immature stage of cellular development before
appearance of the definitive characteristics of the cell.
Blast Crisis
The
stage of chronic myelogenous leukemia in which large quantities
of immature cells are produced by the bone marrow. This stage of
CML is far less responsive to treatment than the chronic (stable)
phase.
Bone
marrow
A substance with the consistency of thick blood found in the body's
hollow bones, such as legs, arms and hips. Marrow produces platelets,
red blood cells and white blood cells, the primary agents of the
body's immune system. Marrow for transplant is usually collected
from the posterior aspect of the pelvic bone (iliac crest).
BMT
Bone
marrow transplant. The process of infusing healthy marrow
into persons who have undergone high-dose chemotherapy for one of
many forms of leukemias, immunodeficiencies, lymphomas, anemias,
metabolic disorders, and in some cases, solid tumors. There
are three types of BMTs" Autologous, related allogeneic and
unrelated allogeneic.
CLL
Chronic
Lymphocytic Leukemia is a malignant disorder involving the over-production
of mature lymphocytes which results in the abnormal accumulation
of these cells in the marrow, the bloodstream and the lymph system.
CLL usually involves the lymph nodes. It usually effects older persons,
with an average age of 60. It is more common in men.
CML
Chronic
Myelogenous Leukemia is a malignant disorder involving the predominance
of granulocytes (a particular type of white cell) of all stages
of development which results in the abnormal accumulation of these
cells in both the bone marrow and the bloodstream. CML may occur
at any age in either sex. It is uncommon before 10 years of age,
and occurs at an average age of 45.
Chemotherapy
Treatment
of a disease using chemicals designed to kill cancer cells.
It is used in large doses to help destroy a patient's diseased marrow
in preparation for a marrow transplant.
CMV
Cytomegalovirus.
A virus which can cause pneumonia in post bone marrow transplant
patients.
Cooley's
Anemia
Another
name for Thalassemia major. See also "Thalassemia".
Conditioning
The
process of preparing the patient to receive donated marrow. Often
done through the use of chemotherapy and radiation therapy.
Congenital
Existing
before or at birth, though not necessarily detected at that time.
The condition may or may not be hereditary.
Congenital
Disorders
Any
disorder present at birth.
CT
Confirmatory
Typing. A repeat tissue typing test done to confirm the compatibility
of the donor and patient. This is one of the final tests done before
transplant.
DNA
Deoxyribonucleic
acid. The material in a cell nucleus that carries genetic information.
Fanconi's
Anemia
A
rare, inherited form of Aplastic Anemia.
GVHD
Graft-versus-host
disease. A condition where the transplanted marrow may react
against the patient's body. GVHD can range in severity from
a minor skin rash to a life threatening disease involving the major
organs of the body.
HCL
Hairy
Cell Leukemia. A rare type or variant of chronic leukemia. Primarily
a disease of middle-aged men. HCL infrequently requires BMT as a
treatment.
Hematopoietic
Blood
forming. Of, or pertaining to, the formation and maturation of blood
cells and their derivatives.
Hemoglobin
The
material in blood which permits the carrying of oxygen.
Hereditary
A
genetic transmission of characteristics from parents to children.
Histiocytosis
A
rare and frequently fatal blood disease that affects the body's
immune system, allowing a type of white blood cell called a histiocyte
to multiply wildly and attack vital body organs. Its cause is unknown,
and its progression is unpredictable.
Histocompatibility
Referring
to the similarity of tissue between different individuals. The level
of histocompatibility describes how well matched the patient and
donor are. The major histocompatibility determinants are the human
leukocyte antigens (HLA). HLA typing is performed between the potential
marrow donor and the potential transplant recipient to determine
how close a HLA match the two are. The closer the match, the less
the donated marrow and the patient's body will react against each
other. (See GVHD).
HLA
Human
leukocyte antigens. The proteins present on the surface of
white blood cell, and most other cells of the body, which allow
the human body to recognize self versus non-self. HLA, A,
B and DR are important in BMT.
HLA typing
The
identification of an individual's specific HLA, A, B and DR..
Hodgkin's
A
lymphoma most frequently occurring in young adults. Hodgkin's disease
not responding to chemotherapy may be treated by autologous BMT
and less frequently by allogeneic BMT.
Leukemia
Any of a group
of potentially fatal diseases involving uncontrolled growth of white
blood cells. Leukemias are classified based upon rapidity of course
of disease and cell type affected.
Lymphocyte
A
type of white blood cell subdivided into T-cells and B-cells. T-cells
provide cellular immunity and B-cells form antibodies. T-cells are
responsible for GVHD.
Lymphoma
Malignant
proliferation of lymphocytes, generally within lymph nodes, but
sometimes involving other tissues such as the liver and spleen.
Lymphoma includes Hodgkin's and Non-Hodgkin's diseases.
Malignant
The
progressive growth of cancerous cells. These cells can spread to
sites distant from the initial site.
Marrow
See
"Bone marrow."
Match
In
marrow transplantation, the word "match" relates to how
similar the HLA typing is between the donor and the recipient. The
best kind of match is an "identical match". This means
that all six of the HLA antigens (2 A antigens, 2 B antigens and
2 DR antigens) are the same between the donor and the recipient.
This type of match is described as a "6 of 6" match. Donors
and recipients who are "mismatched" at one antigen are
considered a "5 of 6" match, and may be considered suitable
for bone marrow transplantation.
MLC
Mixed
Lymphocyte Culture. A test which measures the level of
reactivity between donor and recipient lymphocytes.
Multiple
Myeloma
A
malignant disorder of the plasma cells. Multiple Myeloma is frequently
associated with bone pain and susceptibility to infection.
Myelofibrosis
Also
called agnogenic myeloid metaplasia. A chronic disease characterized
by fibrous material in the bone marrow, an enlarged spleen and anemia.
Myelodysplastic
Also
called pre-leukemia or "smoldering" leukemia, is a syndrome
or disease of the marrow in which syndrome inadequate platelets,
red blood cells and white blood cells are made. Sometimes a precursor
to AML.
Myeloproliferative
A
group of disorders characterized by abnormal proliferation by one
or more types of marrow cells. Four disorders are generally included
as myeloproliferative disorders. These are poly cythemia vera (PV),
myelofibrosis, chronic myelomonocytic leukemia (CMML) and primary
thrombocythemia. Most commonly seen in people over 50 years of age.
Neuroblastoma
A
solid tumor of children, which in an advanced wide spread stage
may be treated by BMT.
Non-Hodgkin's
A
lymphoma which occurs in a wide variety of growth patterns and with
diverse signs and symptoms. Treatment depends upon type of Non-Hodgkin's
lymphoma.
Oligonucleotide
Sequence
of nucleic acids used as a probe in DNA based HLA tissue typing.
Osteopetrosis
A
disorder of the bones in which hardening of tissue obliterates the
marrow, leading to bone failure which may cause early death.
Peripheral
Blood Stem Cells
Cells
with the potential to produce all the components of blood.
Peripheral Blood Stem Cells (PBSC) are obtained from "circulating"
blood rather than from bone marrow.
Platelet
A
component of the blood important in clotting. Inadequate amounts
of platelets will lead to bleeding and bruising easily.
Protocol
A
specific plan for treatment of a disease or disorder.
Relapse
Recurrence
of illness after recovery.
Remission
The
disappearance of cancer cells following treatment. Also the period
during which this reduction or disappearance of symptoms occur.
Sarcoma
A
malignant solid tumor most frequently found in muscle or bone.
SCID
Severe
Combined Immunodeficiency Disease. Congenital defect of the
immune system leading to frequent life threatening infection. Marrow
transplantation is the current treatment of choice. Most patients
have an early onset of SCID detected due to infection, usually by
3 months of age.
Severe aplastic
anemia
See
"Aplastic anemia."
Stem Cells
Those
cells capable of producing all the components of blood and marrow.
T-Cell
See
"Lymphocyte."
Thalassemia
A
group of chronic, inherited anemias. Particularly common in persons
of Mediterranean, African and Southeast Asian ancestry.
Tumor
Any
abnormal mass resulting from the excessive multiplication of cells.
Tumors can be cancerous or non-cancerous.
Unrelated
BMT
See
"Allogeneic."
Wiscott-Aldrich
Syndrome
An
inherited disease effecting the immune system. Chronic skin problems
and frequent infections are characteristics of the disease.
Source: The
National Marrow Donor Program
|
