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The Leukemia/Bone Marrow Transplant Program of BC

Hematology Dictionary
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Diseases due to the uncontrolled growth and division of cells; often-called malignant disease or neoplasia.

A type of fungus, candida infection in the mouth (oral thrush) is a common problem for immunosuppressed patients.

A tube for insertion into the body, usually into a vein, via a sharp needle-type fitting which is then withdrawn from the cannula to allow fluids to pass through the tube.

A substance, which has the ability to cause cells to become cancerous.

The development of cancer.

Cat Scan (CT SCAN)
Computer Assisted Tomography (CAT) is a sophisticated x-ray technique used to produce detailed internal images of the body, particularly the chest and abdomen. The patient lies on a couch which gradually moves through the X-ray machine and the image is built up by a computer as a cross section through the body.

A hollow tube inserted into organs of the body for admitting or removing gases or liquids. For example, for the removal of urine from the bladder.

Cell Biology
The study of the structure, composition and function of cells.

Cell Markers
Biochemical or genetic characteristics, which distinguish and discriminate between different, cell types. HLA antigens are one type of cell marker.

The individual units from which tissues of the body are formed.

Central Nervous System (CNS)
The brain and spinal cord.

Central Venous Line
A catheter passed through a blood vessel into a large central vein, these are used for patients undergoing intensive therapy and provide a route for taking blood samples and administering drugs without repeated needle puncture of a vein. "HICKMAN"® catheter and portacath. "HICKMAN"® is a registered trademark of C.R. Bard, Inc. and its related company, BCR, Inc.

Chemotherapy Treatment using anti-cancer drugs. These may be used singly or in combination to kill or prevent the growth and division of cells. Although aimed at the cancer cells, chemotherapy will also unavoidably affect rapidly dividing normal cells such as in the hair and gut causing hair loss and nausea, which are usually temporary and reversible.

Chromosomes carry the 100,000 genes which provide the inherited blueprint of each individual. In humans there are normally 23 pairs contained in the nucleus of each cell. Alterations in the number or organization of the chromosomes may play a key role in the development of cancer.

Chronic Leukemia
A cancer of the blood of gradual onset and generally of slow progression. May be diagnosed by chance following a routine blood test and prior to the appearance of clinical symptoms.

Chronic Granulocytic Leukemia (CGL)
see Chronic Myeloid Leukemia.

Chronic Lymphocytic Leukemia (CLL)
A slowly progressing form of leukemia, characterized by an increased number of the type of white blood cells known as lymphocytes. With about 2,700 new cases occurring each year in the UK, it is the most common form of leukemia and occurs predominantly in late middle age onwards. It has variable symptoms and course, but may be diagnosed by chance before the patient develops any clinical symptoms of disease.

Chronic Myeloid Leukemia (CML)
A leukemia, which is initially slowly progressing. There are approximately 500 new cases each year in the UK. It is characterized by the presence of large numbers of abnormal, mature granulocytes, circulating in the blood. Sometimes called chronic granulocytic leukemia (CGL).

Chronic Myelomonocytic Leukemia
A form of myelodysplasia characterized by an increase in the number of circulating white blood cells of the monocyte type.

Clinical Trial
A carefully monitored assessment of new forms of treatment. They can vary in design and size from trials of experimental treatments involving small numbers of patients to large national trials, which compare variations in current therapies. A patient will always be informed when the treatment is part of a trial.

A population of genetically identical cells arising from a single parent cell. Leukemia cells originate from one original abnormal cell producing a "leukemic clone".

Clotting Factors
A group of chemical constituents of the blood (factors I to XIII), which interact to make the blood clot.

CNS Leukemia
Invasion of the brain or spinal cord by leukemic cells. This may be diagnosed by examination of the surrounding cerebrospinal fluid.

Clotting of the blood. A complex reaction depending on a series of biochemical components and platelets in the blood. See clotting factors.

"Common" Acute Lymphoblastic Leukemia (CALL)
A sub-type of acute lymphoblastic leukemia affecting cells early in the B lymphocyte lineage, which accounts for about 80% of all cases of acute lymphoblastic leukemia.

A term used to describe deformities or diseases, which are present at the time of birth.

Consolidation Treatment
A course of treatment with anti-cancer drugs given to the patient whilst in remission with the aim of killing any remaining cancerous cells.

Cord Blood
Blood obtained from the umbilical cord at the time of birth and which derives from the baby.

Cord Blood Stem Cells
Stem cells recovered from cord blood, which have been shown to have the capability to repopulate bone marrow and produce blood cells.

Corticosteroids (steroids)
A group of synthetic hormones including prednisone, prednisolone, methylprednisolone and dexamethasone used in the treatment of some leukemia's and myeloma. Also used to suppress graft rejection and graft versus host disease following bone marrow transplant. Side effects include an increased risk of infection.

Cyclosporin A
A drug used to prevent and treat rejection and graft versus host disease in transplant patients by suppressing their normal immune system.

The study of the structure of chromosomes. Cytogenetic tests are carried out on samples of blood and bone marrow taken from leukemia patients to detect any chromosomal abnormalities associated with the disease. These help in the diagnosis and selection of optimal treatment.

A virus, which is harmless in healthy people but may cause serious disease in severely immunosuppressed patients. Particularly dangerous following a bone marrow transplant.

A reduction in the number of cells circulating in the blood.

Cytotoxic Drugs
Anti-cancer drugs which act by killing or preventing the division of cells. See chemotherapy.


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The information in this glossary is cited with permission from the Leukemia Research Foundation web site.

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