GLOSSARY OF TERMS

See Blood Cell Count

A special tube inserted into a large vein in the upper chest. The central line, sometimes referred to as an “indwelling catheter,” is tunnelled under the skin of the chest to keep it firmly in place. The external end of the catheter can be used to administer medications, fluids or blood products or to withdraw blood samples.

With meticulous care, central lines can remain in place for long periods of time (many months) if necessary. They can be capped and remain in place in patients after they leave the hospital, and be used for outpatient chemotherapy or blood product administration. There are several types of catheters (one example is the Hickman) which can be used for patients receiving intensive chemotherapy or nutritional support.

Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It kills cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there
In certain types of leukaemia, particularly acute lymphocytic (lymphoblastic) leukaemia and acute myeloid leukaemia with high blood cell counts, the leukaemic cells have a tendency to enter the covering of the spinal cord and brain (the meninges). This process is often not apparent until months or years after remission when the leukaemia returns, first in the coverings of the CNS, then in the marrow and blood.
To prevent this type of relapse (meningeal leukaemia), virtually all children and adults with acute lymphocytic leukaemia who enter remission are treated with CNS Acute Myeloid Leukaemia prophylaxis. In some cases, x-ray therapy is administered to the head as well. These approaches are very effective in eliminating leukaemia cells in the meninges.

The use of chemicals (drugs or medications) to kill malignant cells. Numerous chemicals have been developed for this purpose, and most act to injure the DNA of the cancer cells. When the DNA is injured, the cells cannot grow or survive.
Successful chemotherapy depends on the fact that malignant cells are somewhat more sensitive to the chemicals than normal cells. Because the cells of the marrow, the gastrointestinal tract, the skin and the hair follicles are most sensitive to these chemicals, injury to these organs causes the common side effects of chemotherapy such as nausea, mouth sores and hair loss.

A solid tumour composed of immature granulocytes, including blast cells. Chloroma’s tend to occur in the brain or spinal cord and the bones, skin, or soft tissue of the head and neck, although they can develop anywhere in the body.
They are usually treated with radiation or chemotherapy. Chloroma’s are an uncommon complication of AML. Other terms for chloroma are “granulocytic sarcoma” and “extramedullary myeloblastoma.”

A chromosome is any of the 46 structures in the nucleus of all cells in the human body
(except the red blood cells) that contain a strand of DNA.
This strand is made up
principally of genes, which are specific stretches of the DNA. “Genome” is the term
for an organism’s complete set of DNA. The human genome has been estimated to
contain about 30,000 genes.
The genes on the X and Y chromosomes are the
determinants of our gender: two X chromosomes produce a female and an X and a Y
chromosome produce a male.
Each chromosome has a long arm (called “q”) and a short
arm (called “p”). The number or size of chromosomes may be altered in blood cancer
cells as a result of chromosome breakage and rearrangement. See Inversion;
Translocation.


Clinical trials are carefully planned and monitored research studies, conducted by
doctors. The goal of clinical trials for blood cancers is to improve treatment and
quality of life and to increase survival. A treatment that is proven safe and effective in
a clinical trial is often approved by the United States Food and Drug Administration
(FDA) for use as a standard treatment if it is more effective or has fewer side effects
than the current standard treatment.

The designation for a population of cells derived from a single transformed parent cell. Virtually all cancers are derived from a single cell with an injury (mutation) to its DNA and thus are monoclonal. Leukaemia, lymphoma, and myeloma are examples of clonal cancers; that is, cancers derived from a single abnormal cell.

A term used with a number to identify a specific molecule on the surface of an immune cell. It is commonly used in its abbreviated form; for example, CD20 (the target of the monoclonal antibody therapy rituximab) and CD52 (the target of the monoclonal antibody therapy Alemtuzumab).

See Growth Factor


See Blood Cell Count


This is the Intensive therapy of a patient with cytotoxic drugs or drugs and total body
radiation just before receiving a stem cell transplant. The therapy serves three purposes. First, it severely depresses the lymphocytes that are the key cells in the recipient’s immune system. This action helps prevent the rejection of the graft (donor tissue). Second, it markedly decreases the number of marrow cells, which may be important to open up the special niches where the transplanted stem cells must lodge to engraft (survive). Third, if the patient is being transplanted for a malignancy, this intensive therapy greatly decreases the numbers of any remaining tumour cells.

Stem cells that are present in blood drained from the placenta and umbilical cord
These stem cells have the capability to repopulate the marrow of a compatible
recipient and produce blood cells. Frozen cord blood is a source of donor stem cells for
transplantation to HLA-matched recipients. Most cord-blood transplants are given by
matched or nearly matched unrelated donors.


A cycle of treatment is an intensive, clustered period of chemotherapy and/or radiation therapy. The therapy may be given for several days or weeks, and this time period represents one cycle of treatment. The treatment plan may call for two, three or more cycles of treatment.

This is the process of analysing the number and size of the chromosomes of cells. In
addition to detecting chromosome alterations, in some cases it is possible to identify
the actual genes that have been affected.
These findings are very helpful in diagnosing
specific types of blood cancers, in determining treatment approaches and in following
the response to treatment. The individual who prepares and examines the
chromosomes and interprets the results is called a cytogeneticist.


Refers to a reduction in the number of cells circulating in the blood.


Anti-cancer drugs that act by killing cells or preventing them from dividing, see
Chemotherapy.